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book_n demonstration_n proposition_n quantity_n 1,827 5 13.9195 5 false
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ID Title Author Corrected Date of Publication (TCP Date of Publication) STC Words Pages
A00429 The elements of geometrie of the most auncient philosopher Euclide of Megara. Faithfully (now first) translated into the Englishe toung, by H. Billingsley, citizen of London. Whereunto are annexed certaine scholies, annotations, and inuentions, of the best mathematiciens, both of time past, and in this our age. With a very fruitfull præface made by M. I. Dee, specifying the chiefe mathematicall scie[n]ces, what they are, and wherunto commodious: where, also, are disclosed certaine new secrets mathematicall and mechanicall, vntill these our daies, greatly missed; Elements. English Euclid.; Dee, John, 1527-1608.; Candale, François de Foix, comte de, 1502-1594.; Billingsley, Henry, Sir, d. 1606. 1570 (1570) STC 10560; ESTC S106699 1,020,889 884

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other_o number_n de_fw-fr be_v of_o a_o other_o number_n fletcher_n and_o let_v ab_fw-la be_v less_o than_o de._n then_o i_o say_v that_o alternate_o also_o what_o part_n or_o part_n ab_fw-la be_v of_o de_fw-fr the_o self_n same_o part_n or_o part_n be_v c_o of_o f._n forasmuch_o as_o what_o part_v ab_fw-la be_v of_o c_o the_o self_n same_o part_n be_v de_fw-fr of_o fletcher_n construction_n therefore_o how_o many_o part_n of_o c_o there_o be_v in_o ab_fw-la so_o many_o part_n of_o fletcher_n also_o be_v there_o in_o de._n divide_v ab_fw-la into_o the_o part_n of_o c_o that_o be_v into_o ag_z and_o gb_o and_o likewise_o de_fw-fr into_o the_o part_n of_o fletcher_n that_o be_v dh_o and_o he._n now_o then_o the_o multitude_n of_o these_o agnostus_n and_o gb_o be_v equal_a unto_o the_o multitude_n of_o these_o dh_o and_o he._n demonstration_n and_o forasmuch_o as_o what_o part_n agnostus_n be_v of_o c_o the_o self_n same_o part_n be_v dh_o of_o fletcher_n therefore_o alternate_o also_o by_o the_o former_a what_o part_n or_o part_n agnostus_n be_v of_o dh_o the_o self_n same_o part_n or_o part_n be_v c_o of_o f._n and_o by_o the_o same_o reason_n also_o what_o part_n or_o part_n gb_o be_v of_o he_o the_o same_o part_n or_o part_n be_v c_o of_o f._n wherefore_o what_o part_n or_o part_n agnostus_n be_v of_o dh_o the_o self_n same_o part_n or_o part_n be_v ab_fw-la of_o de_fw-fr by_o the_o 6._o of_o the_o seven_o but_o what_o part_n or_o part_n agnostus_n be_v of_o dh_o the_o self_n same_o part_n or_o part_n be_v it_o prove_v that_o c_z be_v of_o f._n wherefore_o what_o part_n or_o part_n ab_fw-la be_v of_o d_o e_o the_o self_n same_o part_n or_o part_n be_v c_o of_o fletcher_n which_o be_v require_v to_o be_v prove_v ¶_o the_o 9_o theorem_a the_o 11._o proposition_n if_o the_o whole_a be_v to_o the_o whole_a as_o a_o part_n take_v away_o be_v to_o a_o part_n take_v away_o then_o shall_v the_o residue_n be_v unto_o the_o residue_n as_o the_o whole_a be_v to_o the_o whole_a quantity_n svppose_v that_o the_o whole_a number_n ab_fw-la be_v unto_o the_o whole_a number_n cd_o as_o the_o part_n take_v away_o ae_n be_v to_o the_o part_n take_v away_o cf._n then_o i_o say_v that_o the_o residue_n ebb_n be_v to_o the_o residue_n fd_o as_o the_o whole_a ab_fw-la be_v to_o the_o whole_a cd_o for_o forasmuch_o as_o ab_fw-la be_v to_o cd_o as_o ae_n be_v to_o cf_o therefore_o what_o part_n or_o part_n ab_fw-la be_v of_o cd_o the_o self_n same_o part_n or_o part_n be_v ae_n of_o cf._n wherefore_o also_o the_o residue_n ebb_n be_v of_o the_o residue_n fd_o by_o the_o 8._o of_o the_o seven_o the_o self_n same_o part_n o●_n part_n that_o ab_fw-la be_v of_o cd_o demonstration_n wherefore_o also_o by_o the_o 21._o definition_n of_o this_o book_n as_o ebb_n be_v to_o fd_o so_o be_v ab_fw-la to_o cd_o which_o be_v require_v to_o be_v prove_v ¶_o the_o 10._o theorem_a the_o 12._o proposition_n if_o there_o be_v a_o multitude_n of_o number_n how_o many_o soever_o proportional_a as_o one_o of_o the_o antecedentes_fw-la be_v to_o one_o of_o the_o consequentes_fw-la so_o be_v all_o the_o antecedentes_fw-la to_o all_o the_o consequentes_fw-la svppose_v that_o there_o be_v a_o multitude_n of_o number_n how_o many_o soever_o proportional_a namely_o a_o b_o c_o d_o so_fw-mi that_o as_o a_o be_v to_o b_o so_o let_v c_o be_v to_o d._n quantity_n then_o i_o say_v that_o as_o one_o of_o the_o antecedentes_fw-la namely_o a_o be_v to_o one_o of_o the_o consequentes_fw-la namely_o to_o b_o or_o as_z c_z be_v to_o d_z so_o be_v all_o the_o antecedentes_fw-la namely_o a_o and_o c_o to_o all_o the_o consequentes_fw-la namely_o to_o b_o and_o d._n for_o forasmuch_o as_o by_o supposition_n as_o a_o be_v to_o b_o so_o be_v c_z to_o d_z therefore_o what_o part_n or_o part_n a_o be_v of_o b_o the_o self_n same_o part_n or_o part_n be_v c_z of_o d_z by_o the_o 21._o definition_n of_o this_o book_n wherefore_o alternate_o what_o part_n or_o part_n a_o be_v of_o c_o the_o self_n same_o part_n or_o part_n be_v b_o of_o d_z by_o the_o nine_o and_o ten_o of_o the_o seven_o wherefore_o both_o these_o number_n add_v together_o demonstration_n a_o and_o c_o be_v of_o both_o these_o numbers_z b_o and_o d_z add_v together_o the_o self_n same_o part_n or_o part_n that_o a_o be_v of_o b_o by_o the_o 5._o and_o 6._o of_o the_o seven_o wherefore_o by_o the_o 21._o definition_n of_o the_o seven_o as_o one_o of_o the_o antecedent_n namely_o a_o be_v to_o one_o of_o the_o consequentes_fw-la namely_o to_o b_o so_o be_v all_o the_o antecedentes_fw-la a_fw-la and_o c_o to_o all_o the_o consequentes_fw-la b_o &_o d._n which_o be_v require_v to_o be_v prove_v ¶_o the_o 11._o theorem_a the_o 13._o proposition_n if_o there_o be_v four_o number_n proportional_a then_o alternate_o also_o they_o shall_v be_v proportional_a svppose_v that_o there_o be_v four_o number_n proportional_a quantity_n a_o b_o c_o d_o so_fw-mi that_o as_o a_o be_v to_o b_o so_o let_v c_o be_v to_o d._n then_o i_o say_v that_o alternate_o also_o they_o shall_v be_v proportional_a that_o be_v as_o a_o be_v to_o c_o so_o be_v b_o to_o d._n for_o forasmuch_o as_o by_o supposition_n as_o a_o be_v to_o b_o so_o be_v c_z to_o d_z therefore_o by_o the_o 21._o definition_n of_o this_o book_n what_o part_n or_o part_n a_o be_v of_o b_o the_o self_n same_o part_n or_o part_n be_v c_o of_o d._n therefore_o alternate_o what_o part_n or_o part_n a_o be_v of_o c_o the_o self_n same_o part_n or_o part_n be_v b_o of_o d_z by_o the_o 9_o of_o the_o seven_o &_o also_o by_o the_o 10._o of_o the_o same_o wherefore_o as_o a_o be_v to_o c_o so_o be_v b_o to_o d_z by_o the_o 21._o definition_n of_o this_o book_n which_o be_v require_v to_o be_v prove_v here_o be_v to_o be_v note_v that_o although_o in_o the_o foresay_a example_n and_o demonstration_n the_o number_n a_o be_v suppose_v to_o be_v less_o than_o the_o number_n b_o and_o so_o the_o number_n c_o be_v less_o than_o the_o number_n d_o note_n yet_o will_v the_o same_o serve_v also_o though_o a_o be_v suppose_v to_o be_v great_a than_o b_o whereby_o also_o c_o shall_v be_v great_a than_o d_z as_z in_o th●s_n example_n here_o put_v for_o for_o that_o by_o supposition_n as_o a_o be_v to_o b_o so_o be_v c_z to_o d_z and_o a_o be_v suppose_v to_o be_v great_a than_o b_o and_o c_z great_a than_o d_z therefore_o by_o the_o 21._o definition_n of_o this_o book_n how_o multiplex_n a_o be_v to_o b_o so_o multiplex_n be_v c_o to_o d_z and_o therefore_o what_o part_n or_o part_n b_o be_v of_o a_o the_o self_n same_o part_n or_o part_n be_v d_z of_o c._n wherefore_o alternate_o what_o part_n or_o part_n b_o be_v of_o d_o the_o self_n same_o part_n or_o part_n be_v a_o of_o c_o and_o therefore_o by_o the_o same_o definition_n b_o be_v to_o d_z as_z a_o be_v to_o c._n and_o so_o must_v you_o understand_v of_o the_o former_a proposition_n next_o go_v before_o ¶_o the_o 12._o theorem_a the_o 14._o proposition_n if_o there_o be_v a_o multitude_n of_o number_n how_o many_o soever_o and_o also_o other_o number_n equal_a unto_o they_o in_o multitude_n which_o be_v compare_v two_o and_o two_o be_v in_o one_o and_o the_o same_o proportion_n they_o shall_v also_o of_o equality_n be_v in_o one_o and_o the_o same_o proportion_n quantity_n svppose_v that_o there_o be_v a_o multitude_n of_o number_n how_o many_o soever_o namely_o a_o b_o c_o and_o let_v the_o other_o number_n equal_a unto_o they_o in_o multitude_n be_v d_o e_o f_o which_o be_v compare_v two_o and_o two_o let_v be_v in_o one_o and_o the_o same_o proportion_n that_o be_v as_z a_o to_o b_o so_o let_v d_o be_v to_o e_o and_o as_o b_o be_v to_o c_o so_o let_v e_o be_v to_o f._n then_o i_o say_v that_o of_o equality_n as_o a_o be_v to_o c_o so_o be_v d_z to_o f._n for_o forasmuch_o as_o by_o supposition_n as_o a_o be_v to_o b_o so_o be_v d_z to_o e_o therefore_o alternate_o also_o by_o the_o 13_o of_o the_o seven_o as_o a_o be_v to_o d_o so_o be_v b_o to_o e._n again_o for_o that_o as_z b_o be_v to_o c_o so_o be_v e_o to_o fletcher_n demonstration_n therefore_o alternate_o also_o by_o the_o self_n same_o as_z b_o be_v to_o e_o so_o be_v c_o to_o f._n but_o as_o b_o be_v to_o e_o so_o be_v a_o to_o d._n wherefore_o by_o the_o seven_o common_a sentence_n of_o the_o seven_o as_o a_o be_v to_o d_o so_o be_v c_o to_o f._n wherefore_o alternate_o by_o the_o 13._o of_o the_o seven_o as_o a_o be_v to_o c_o so_o be_v d_z to_o fletcher_n which_o
it_o comprehend_v wherefore_o the_o pyramid_n who_o base_a be_v the_o square_n abcd_o and_o altitude_n the_o self_n same_o that_o the_o cone_fw-mi have_v be_v great_a than_o the_o half_a of_o the_o cone_fw-it divide_v by_o the_o 30._o of_o the_o three_o every_o one_o of_o the_o circumference_n ab_fw-la bc_o cd_o and_o dam_n into_o two_o equal_a part_n in_o the_o point_n e_o f_o g_o and_o h_o and_o draw_v these_o right_a line_n ae_n ebb_n bf_o fc_o cg_o gd_o dh_o and_o ha._n wherefore_o every_o one_o of_o these_o triangle_n aeb_fw-mi bfc_n cgd_v and_o dha_n be_v great_a than_o the_o half_a part_n of_o the_o segment_n of_o the_o circle_n describe_v about_o it_o upon_o every_o one_o of_o these_o triangle_n aeb_fw-mi bfc_n cgd_v and_o dha_n describe_v a_o pyramid_n of_o equal_a altitude_n with_o the_o cone_n and_o after_o the_o same_o manner_n every_o one_o of_o those_o pyramid_n so_o describe_v be_v great_a than_o the_o half_a part_n of_o the_o segment_n of_o the_o cone_fw-it set_v upon_o the_o segment_n of_o the_o circle_n now_o therefore_o divide_v by_o the_o 30_o of_o the_o three_o the_o circumference_n remain_v into_o two_o equal_a part_n &_o draw_v right_a line_n &_o raise_v up_o upon_o every_o one_o of_o those_o triangle_n a_o pyramid_n of_o equal_a altitude_n with_o the_o cone_n and_o do_v this_o continual_o we_o shall_v at_o the_o length_n by_o the_o first_o of_o the_o ten_o leave_v certain_a segment_n of_o the_o cone_n which_o shall_v be_v less_o then_o the_o excess_n whereby_o the_o cone_n exceed_v the_o three_o part_n of_o the_o cylinder_n let_v those_o segment_n be_v ae_n ebb_n bf_o fc_o cg_o gd_o dh_o and_o ha._n wherefore_o the_o pyramid_n remain_v who_o base_a be_v the_o poligonon_n figure_n aebfcgdh_n and_o altitude_n the_o self_n same_o with_o the_o cone_n be_v great_a than_o the_o three_o part_n of_o the_o cylinder_n but_o the_o pyramid_n who_o base_a be_v the_o polygonon_n figure_n aebfcgdh_n and_o altitude_n the_o self_n same_o with_o the_o cone_n be_v the_o three_o part_n of_o the_o prism_n who_o base_a be_v the_o poligonon_n figure_n aebfcgdh_n and_o altitude_n the_o self_n same_o with_o the_o cylinder_n wherefore_o you_o the_o prism_n who_o base_a be_v the_o polygonon_n figure_n aebfcgdh_n and_o altitude_n the_o self_n same_o with_o the_o cylinder_n be_v great_a than_o the_o cylinder_n who_o base_a be_v the_o circle_n abcd._n but_o it_o be_v also_o less_o for_o it_o be_v contain_v of_o it_o which_o be_v impossible_a wherefore_o the_o cylinder_n be_v not_o in_o less_o proportion_n to_o the_o cone_n then_o in_o treble_a proportion_n and_o it_o be_v prove_v that_o it_o be_v not_o in_o great_a proportion_n to_o the_o cone_n then_o in_o treble_a proportion_n wherefore_o the_o cone_n be_v the_o three_o part_n of_o the_o cylinder_n wherefore_o every_o cone_n be_v the_o three_o part_n of_o a_o cylinder_n have_v one_o &_o the_o self_n same_o base_a and_o one_o and_o the_o self_n same_o altitude_n with_o it_o which_o be_v require_v to_o be_v demonstrate_v ¶_o add_v by_o m._n john_n dee_n ¶_o a_o theorem_a 1._o the_o superficies_n of_o every_o upright_o cylinder_n except_o his_o base_n be_v equal_a to_o that_o circle_n who_o semidiameter_n be_v middle_a proportional_a between_o the_o side_n of_o the_o cylinder_n and_o the_o diameter_n of_o his_o base_a ¶_o a_o theorem_a 2._o the_o superficies_n of_o every_o upright_o or_o isosceles_a cone_n except_o the_o base_a be_v equal_a to_o that_o circle_n who_o semidiameter_n be_v middle_a proportional_a between_o the_o side_n of_o that_o cone_n and_o the_o semidiameter_n of_o the_o circle_n which_o be_v the_o base_a of_o the_o cone_n my_o intent_n in_o addition_n be_v not_o to_o amend_v euclide●_n method_n which_o need_v little_a add_v or_o none_o at_o all_o but_o my_o desire_n be_v somewhat_o to_o furnish_v you_o towards_o a_o more_o general_a art_n mathematical_a them_z euclides_n element_n addition_n remain_v in_o the_o term_n in_o which_o they_o be_v write_v can_v sufficient_o help_v you_o unto_o and_o though_o euclides_n element_n with_o my_o addition_n run_v not_o in_o one_o methodical_a race_n towards_o my_o mark_n yet_o in_o the_o mean_a space_n my_o addition_n either_o geve_v light_a where_o they_o be_v annex_v to_o euclides_n matter_n or_o geve_v some_o ready_a aid_n and_o show_v the_o way_n to_o dilate_v your_o discourse_n mathematical_a or_o to_o invent_v and_o practice_v thing_n mechanical_o and_o in_o deed_n if_o more_o leysor_n have_v happen_v many_o more_o strange_a matter_n mathematical_a have_v according_a to_o my_o purpose_n general_a be_v present_o publish_v to_o your_o knowledge_n but_o want_v of_o due_a leasour_n cause_v you_o to_o want_v that_o which_o my_o good_a will_n towards_o you_o most_o hearty_o do_v wish_v you_o as_o concern_v the_o two_o theorem_n here_o annex_v their_o verity_n be_v by_o archimedes_n in_o his_o book_n of_o the_o sphere_n and_o cylinder_n manifest_o demonstrate_v and_o at_o large_a you_o may_v therefore_o bold_o trust_v to_o they_o and_o use_v they_o as_o supposition_n in_o any_o your_o purpose_n till_o you_o have_v also_o their_o demonstration_n but_o if_o you_o well_o remember_v my_o instruction_n upon_o the_o first_o proposition_n of_o this_o book_n and_o my_o other_o addition_n upon_o the_o second_o with_o the_o supposition_n how_o a_o cylinder_n and_o a_o cone_n be_v mathematical_o produce_v you_o will_v not_o need_v archimedes_n demonstration_n nor_o yet_o be_v utter_o ignorant_a of_o the_o solid_a quantity_n of_o this_o cylinder_n and_o cone_n here_o compare_v the_o diameter_n of_o their_o base_a and_o heith_n be_v know_v in_o any_o measure_n neither_o can_v their_o crooked_a superficies_n remain_v unmeasured_a whereof_o undoubted_o great_a pleasure_n and_o commodity_n may_v grow_v to_o the_o sincere_a student_n and_o precise_a practiser_n ¶_o the_o 11._o theorem_a the_o 11._o proposition_n cones_n and_o cylinder_n be_v under_o one_o and_o the_o self_n same_o altitude_n be_v in_o that_o proportion_n the_o one_o other_o that_o their_o base_n be_v in_o like_a sort_n also_o may_v we_o prove●_v that_o as_o the_o circle_n efgh_o be_v to_o the_o circle_n abcd_o so_o be_v not_o the_o cone_n en_fw-fr to_o any_o solid_a less_o than_o the_o cone_n al._n now_o i_o say_v that_o as_o the_o circle_n abcd_o be_v to_o the_o circle_n efgh_o so_o be_v not_o the_o cone_n all_o to_o any_o solid_a great_a than_o the_o cone_fw-mi en_fw-fr for_o if_o it_o be_v possible_a let_v it_o be_v unto_o a_o great_a namely_o to_o the_o solid_a x._o wherefore_o by_o conversion_n as_o the_o circle_n efgh_o be_v to_o the_o circle_n abcd_o so_o be_v the_o solid_a x_o to_o the_o cone_n all_o but_o as_o the_o solid_a x_o be_v to_o the_o cone_n all_o so_o be_v the_o cone_n en_fw-fr to_o some_o solid_a less_o than_o the_o cone_n all_o as_o we_o may_v see_v by_o the_o assumpt_n put_v after_o th●_z second_o of_o this_o book_n wherefore_o by_o the_o 11._o of_o the_o five_o as_o the_o circle_n efgh_o be_v to_o the_o circle_n abcg●_n so_o be_v the_o cone_n en_fw-fr to_o some_o solid_a less_o than_o the_o cone_n all_o which_o we_o have_v prove_v to_o be_v impossible_a wherefore_o as_o the_o circle_n abcd_o be_v to_o the_o circle_n efgh_o so_o be_v not_o the_o cone_n all_o to_o any_o solid_a great_a than_o the_o cone_fw-mi en_fw-fr and_o it_o be_v also_o prove_v that_o it_o be_v not_o to_o any_o less_o wherefore_o as_o the_o circle_n abcd_o be_v to_o the_o circle_n efgh_o so_o be_v the_o cone_n all_o to_o the_o cone_n en_fw-fr but_o as_o the_o cone_n be_v to_o the_o cone_n so_o be_v the_o cylinder_n to_o the_o cylinder_n by_o the_o 15._o of_o the_o five_o for_o the_o one_o be_v in_o treble_a proportion_n to_o the_o other_o cylinder_n wherefore_o by_o the_o 11._o of_o the_o five_o as_o the_o circle_n abcd_o be_v to_o the_o circle_n efgh_o so_o be_v the_o cylinder_n which_o be_v set_v upon_o they_o the_o one_o to_o the_o other_o the_o say_a cylinder_n being_n under_o equal_a altitude_n with_o the_o cones_fw-la cones_n therefore_o and_o cylinder_n be_v under_o one_o &_o the_o self_n same_o altitude_n be_v in_o that_o proportion_n the_o one_o to_o the_o other_o that_o their_o base_n be_v which_o be_v require_v to_o be_v demonstrate_v ¶_o the_o 12._o theorem_a the_o 12._o proposition_n like_a cones_n and_o cylinder_n be_v in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n of_o their_o base_n be_v now_o also_o i_o say_v that_o the_o cone_fw-mi abcdl_n be_v not_o to_o any_o solid_a great_a than_o the_o cone_n efghn_n case_n in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n bd_o be_v to_o the_o diameter_n fh_o for_o if_o it_o be_v possible_a let_v it_o be_v to_o a_o great_a namely_o to_o the_o solid_a x._o wherefore_o by_o conversion_n by_o the_o
construction_n two_o case_n in_o this_o proposition_n first_o case●_n second_o case_n demonstration_n construction_n demonstration_n construction_n demonstration_n an_o other_o way_n after_o peli●arius_n construction_n demonstration_n construction_n demonstration_n demonstration_n lead_v to_o a_o impossibility_n three_o case_n in_o this_o proposition_n the_o three_o case_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n a_o proposition_n add_v by_o petarilius_n note_n construction_n demonstration_n an_o other_o way_n also_o after_o pelitarius_n construction_n demonstration_n an_o other_o way_n to_o do_v the_o sam●_n after_o pelitarius_n demonstration_n demonstration_n demonstration_n lead_v to_o a_o absurdity_n a_o corollary_n construction_n demonstration_n demonstration_n a_o ●ther_n way_n to_o do_v the_o same_o after_o orontius_n an_o other_o way_n after_o pelitarius_n construction_n demonstration_n a_o addition_n of_o flussates_n flussates_n a_o poligonon_n figure_n be_v a_o figure_n consist_v of_o many_o side_n the_o argument_n of_o this_o five_o book_n the_o first_o author_n of_o this_o book_n eudoxus_n the_o first_o definition_n a_o part_n take_v two_o manner_n of_o way_n the_o fi●st_a way_n the_o second_o way_n how_o a_o less_o quantity_n be_v say_v to_o measure_v a_o great_a in_o what_o signification_n euclid_n here_o take_v a_o part_n par●_n metien●_n or_o mensuran●_n pars_fw-la multiplicati●a_fw-la pars_fw-la aliquota_fw-la this_o kind_n of_o part_n common_o use_v in_o arithmetic_n the_o other_o kind_n of_o part_n pars_fw-la constit●ens_fw-la or_o componens_fw-la pars_fw-la aliquanta_fw-la the_o second_o definition_n number_n very_o necessary_a for_o the_o understanding_n of_o this_o book_n and_o the_o other_o book_n follow_v the_o t●ird_o definition_n rational_a proportion_n divide_v ●●to_o two_o kind_n proportion_n of_o equality_n proportion_n of_o inequality_n proportion_n of_o the_o great_a to_o the_o less_o multiplex_fw-la duple_n proportion_n triple_a quadruple_a quintuple_a superperticular_a sesquialtera_fw-la sesquitertia_fw-la sesquiquarta_fw-la superpartiens_fw-la superbipartiens_fw-la supertripartiens_fw-la superquadripartiens_fw-la superquintipartiens_fw-la multiplex_fw-la superperticular_a dupla_fw-la sesquialtera_fw-la dupla_fw-la sesquitertia_fw-la tripla_fw-la sesquialtera_fw-la multiplex_fw-la superpartiens_fw-la dupla_fw-la superbipartiens_fw-la dupla_fw-la supertripartiens_fw-la tripla_fw-la superbipartiens_fw-la tripla_fw-la superquad●ipartiens_fw-la how_o to_o kno●_n the_o denomination_n of_o any_o proportion_n proportion_n of_o the_o less_o in_o the_o great_a submultiplex_fw-la subsuperparticular_a subsuperpertient_fw-fr etc_n etc_n the_o four_o definition_n example_n of_o this_o definition_n in_o magnitude_n example_n thereof_o in_o number_n note_n the_o five_o definition_n a_o example_n of_o this_o definition_n in_o magnitude_n why_o euclid_n in_o define_v of_o proportion_n use_v multiplication_n the_o six_o definition_n a_o example_n of_o this_o definitiin_n in_o magnitude_n a_o example_n in_o number_n an_o other_o example_n in_o number_n an_o other_o example_n in_o number_n note_v this_o particle_n according_a to_o any_o multiplication_n a_o example_n where_o the_o equimultiplice_n of_o the_o first_o and_o three_o excee_v the_o equimultiplice_n of_o the_o second_o and_o four_o and_o yet_o the_o quantity_n give_v be_v not_o in_o one_o and_o the_o self_n same_o proportion_n a_o rule_n to_o produce_v equimultiplice_n of_o the_o first_o and_o three_o equal_a to_o the_o equimultiplice_n of_o the_o second●_n and_o forth_o example_n thereof_o the_o seven_o definition_n 9_z 12_o 3_o 4_o proportionality_n of_o two_o sort_n continual_a and_o discontinuall_a a_o example_n of_o continual_a proportionality_n in_o number_n 16.8.4.2.1_o in_o coutinnall_a proportionality_n the_o quantity_n can_v be_v of_o one_o kind_n discontinuall_a prop●rtionalitie_n example_n of_o discontinual_a proportionality_n in_o number_n in_o discontinual_a proportionality_n the_o proportion_n may_v be_v of_o diverse_a kind_n the_o eight_o definition_n a_o example_n of_o this_o definition_n in_o magnitude_n a_o example_n in_o number_n note_n the_o nine_o definition_n a_o example_n of_o this_o definition_n in_o magnitude_n example_n ●n_a number_n the_o ten_o definition_n a_o rule_n to_o add_v proportion_n to_o proportion_n 8._o 4._o 2._o 1._o 2_o 2_o 2_o 1_o 1_o 1_o the_o eleven_o definition_n example_n of_o this_o definition_n in_o magnitude_n example_n in_o number_n the_o twelf●h_o definition_n example_n of_o this_o definition_n in_o magnitud_n example_n in_o number_n the_o thirteen_o definition_n example_n of_o this_o definition_n in_o magnitud_n example_n in_o number_n the_o fourteen_o definition_n example_n of_o this_o definition_n in_o magnitud_n example_n in_o number_n the_o fi●t●ne_a definition_n this_o be_v the_o converse_n of_o the_o former_a definition_n example_n in_o magnitude_n example_n in_o number_n the_o sixteen_o definition_n a_o example_n of_o this_o definition_n in_o magnitude_n a_o example_n in_o number_n the_o sevententh_n definition_n a_o example_n of_o this_o definition_n in_o magnitude_n a_o example_n in_o number_n note_n the_o eighttenth_n definition_n a_o example_n of_o this_o definition_n in_o magnitude_n example_n in_o number_n the_o nineteen_o definition_n a_o example_n of_o this_o definition_n in_o magnitude_n example_n in_o number_n the_o 20._o definition_n the_o 2d_o definition_n these_o two_o last_o definition_n not_o find_v in_o the_o greek_a exampler_n construction_n demonstration_n demonstration●_n construction_n demonstration_n construction_n demonstration_n alemmae_fw-la or_o a_o assumpt_n a_o corollary_n converse_v proportion_n construction_n demonstration_n two_o case_n in_o this_o propotion_n the_o second_o the_o second_o part_n demonstrate_v the_o first_o part_n of_o this_o proposition_n demonstrate_v the_o second_o part_n of_o the_o proposition_n demonstrate_v first_o differ●c●_n of_o the_o first_o part_n demonstrati●_n of_o t●e_z same_o first_o difference_n second_o difference_n three_o difference_n the_o second_o part_n ●f_o this_o proposition_n the_o first_o par●_n of_o this_o proposition_n demonstrate_v the_o second_o part_n prove_v the_o first_o part_n of_o this_o proposition_n prove_v the_o second_o part_n demonstrate_v construction_n demonstration●_n constr●ction_n demonstration●_n construction_n demonstration_n a_o addition_n of_o campane_n demonstration_n construction_n demonstration_n demonstration_n of_o alternate_a proportion_n construction_n demonstration_n demonstration_n of_o proportion_n by_o division_n construction_n demonstration_n demonstration_n of_o proportion_n by_o composition_n this_o proposition_n be_v the_o converse_n of_o the_o former_a demonstration●e●aing_v to_o a_o impossibility_n that_o which_o the_o five_o of_o this_o book_n prove_v only_o touch_v multiplices_fw-la this_o prove_v general_o of_o all_o magnitude_n alemma_n a_o corollary_n conversion_n of_o proportion_n this_o proposition_n pertain_v to_o proportion_n of_o equality_n inordinate_a proportionality_n the_o second_o difference_n the_o three_o difference_n th●r_a proposition_n pertain_v to_o proportion_n of_o equality_n in_o perturbate_n proportionality_n the_o three_o difference_n proportion_n of_o equality_n in_o ordinate_a proportionality_n construction_n demonstration_n when_o there_o be_v more_o than_o three_o magnitude_n in_o either_o order_n a●cde●gh_n proportion_n of_o equality_n in_o perturbate_n proprotionalitie_n construction_n demonstration_n note_n that_o which_o the_o second_o proposition_n of_o this_o book_n prove_v only_o touch_v multiplices_fw-la be_v here_o prove_v general_o touch_v magnitude_n an_o other_o demonstration_n of_o the_o same_o affirmative_o an_o other_o 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first_o part_n of_o this_o proposition_n demonstration_n of_o the_o of_o the_o same_o the_o second_o part_n which_o be_v the_o converse_n of_o the_o first_o the_o first_o par●_n of_o this_o proposition_n demonstration_n of_o the_o same_o the_o second_o part_n which_o be_v the_o converse_n of_o the_o first_o demonstration_n of_o the_o first_o part_n the_o second_o part_n which_o be_v the_o converse_n of_o the_o first_o the_o first_o part_n of_o th●●_n theorem_a the_o second_o part_n which_o be_v the_o converse_n of_o the_o first_o a_o corollary_n description_n of_o the_o rectiline_a figure_n require_v demonstration_n demonstration_n a_o corollary_n the_o first_o par●_n of_o this_o theorem_a the_o second_o part_n demonstrate_v the_o three_o part_n the_o first_o corollary_n the_o second_o corollary_n demonstration_n the_o first_o part_n of_o this_o proposition_n the_o second_o part_n which_o be_v the_o converse_n of_o the_o first_o first_o note_v that_o this_o be_v prove_v in_o the_o 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second_o part_n of_o the_o first_o case_n the_o second_o case_n first_o part_n of_o the_o second_o case_n second_o part_n of_o the_o second_o case_n construction_n two_o case_n in_o this_o proposition_n the_o first_o case_n the_o first_o part_n of_o the_o first_o case_n 〈◊〉_d second_o 〈◊〉_d of_o the_o 〈◊〉_d case_n the_o second_o case_n a_o corollary_n the_o first_o senary_a by_o substraction_n demonstration_n an_o other_o demonstration_n after_o campane_n definition_n of_o the_o eight_o irrational_a line_n definition_n of_o 〈◊〉_d ●inth_o irrational_a line_n an_o other_o demonstration_n after_o campane_n construction_n demonstration_n definition_n of_o the_o ten_o irrational_a line_n definition_n of_o the_o eleven_o irrational_a line_n ●●●●i●ition_n of_o the_o twelve_o irra●ionall_a line_n definition_n of_o the_o thirteen_o and_o last_o irrational_a line_n a_o assumpt_n of_o campane_n i_o dee_n though_o campane_n lemma_n be_v true_a ye●_z the_o manner_n of_o demonstrate_v it_o narrow_o 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which_o require_v some_o action_n or_o do_v as_o the_o make_v of_o some_o ●igure_n or_o to_o divide_v a_o figure_n or_o line_n to_o apply_v figure_n to_o ●igure_n to_o add_v figure_n together_o or_o to_o subtrah_n one_o from_o a_o other_o to_o describe_v to_o inscribe_v to_o circumscribe_v one_o figure_n within_o or_o without_o another_o and_o such_o like_a as_o of_o the_o first_o proposition_n of_o the_o first_o book_n be_v a_o problem_n which_o be_v thuss_v upon_o a_o right_a line_n give_v not_o be_v infinite_a to_o describe_v a_o equilater_n triangle_n or_o a_o triangle_n of_o three_o equal_a side_n for_o in_o it_o beside_o the_o demonstration_n and_o contemplation_n of_o the_o mind_n be_v require_v somewhat_o to_o be_v do_v name_o to_o make_v a_o equilater_n triangle_n upon_o a_o line_n give_v and_o in_o the_o end_n of_o every_o problem_n after_o the_o demonstration_n be_v conclude_v a●ter_v this_o man●er_n which_o be_v the_o thing_n which_o be_v require_v to_o be_v do_v be_v a_o theorem_a be_v a_o proposition_n which_o require_v the_o search_a ou●_n and_o demonstration_n of_o some_o property_n or_o passion_n of_o some_o figure_n wherein_o be_v only_a speculation_n and_o contemplation_n of_o mind_n without_o do_v or_o work_v of_o any_o thing_n as_o the_o five_o proposition_n of_o the_o first_o book_n which_o be_v thus_o a_o isosceles_a or_o triangle_n of_o two_o equal_a side_n have_v his_o angle_n at_o th●_z base_a equal_a the_o one_o to_o the_o other_o etc_n etc_n be_v a_o theorem_a for_o in_o it_o be_v require_v only_o to_o be_v prove_v and_o make_v plain_a by_o reason_n and_o demonstration_n that_o these_o two_o angle_n be_v equal_a without_o further_a work_n or_o do_v and_o in_o the_o end●_n of_o ●u●ry_a theorem_a after_o the_o demonstration_n be_v conclude_v after_o this_o manner_n which_o thing_n be_v require_v to_o be_v demonstrate_v or_o prove_v the_o first_o problem_n the_o first_o proposition_n upon_o a_o right_a line_n give_v not_o be_v infinite_a to_o describe_v a_o equilater_n triangle_n or_o a_o triangle_n of_o three_o equal_a side_n svppose_v that_o the_o right_a line_n give_v be_v ab_fw-la it_o be_v require_v upon_o the_o line_n ab_fw-la to_o describe_v a_o equilater_n triangle_n namely_o a_o triangle_n of_o three_o equal_a side_n construction_n now_o therefore_o make_v the_o centre_n the_o point_n a_o and_o the_o space_n ab_fw-la describe_v by_o the_o three_o petition_n a_o circle_n bcd_o and_o again_o by_o the_o same_o make_v the_o centre_n the_o point_n b_o and_o the_o space_n b●_n describe_v a_o other_o circle_n ace_n and_o by_o the_o first_o petition_n from_o the_o point_n c_o wherein_o the_o circle_n cut_v the_o one_o the_o other_o draw_v one_o right_a line_n to_o the_o point_n a_o and_o a_o other_o right_a line_n to_o the_o point_n b._n and_o forasmuch_o as_o the_o point_n a_o be_v the_o centre_n of_o the_o circle_n cbd_v demonstration_n therefore_o by_o the_o 15._o definition_n the_o line_n ac_fw-la be_v equal_a to_o the_o line_n ab_fw-la again_o forasmuch_o as_o the_o point_n b_o be_v the_o centre_n of_o the_o circle_n caesar_n therefore_o by_o the_o same_o definition_n the_o line_n bc_o be_v equal_a to_o the_o line_n basilius_n and_o it_o be_v prove_v that_o the_o line_n ac_fw-la be_v equal_a to_o the_o line_n ab_fw-la wherefore_o either_o of_o these_o line_n ca_n and_o cb_o be_v equal_a to_o the_o line_n ab_fw-la but_o thing_n which_o be_v equal_a to_o one_o and_o the_o same_o thing_n be_v also_o equal_a the_o one_o to_o the_o other_o by_o the_o first_o common_a sentence_n wherefore_o the_o line_n ca_n also_o be_v equal_a to_o the_o line_n cb._n wherefore_o these_o three_o right_a line_n ca_n ab_fw-la and_o bc_o be_v equal_a the_o one_o to_o the_o other_o wherefore_o the_o triangle_n abc_n be_v equilater_n wherefore_o upon_o the_o line_n ab_fw-la be_v describe_v a_o equilater_n triangle_n abc_n wherefore_o upon_o a_o line_n give_v not_o be_v infinite_a there_o be_v describe_v a_o equilater_n triangle_n which_o be_v the_o thing_n which_o be_v require_v to_o be_v do_v a_o triangle_n or_o any_o other_o rectiline_v figure_n be_v then_o say_v to_o be_v set_v or_o describe_v upon_o a_o line_n when_o the_o line_n be_v one_o of_o the_o side_n of_o the_o figure_n this_o first_o proposition_n be_v a_o problem_n because_o it_o require_v act_n or_o do_v namely_o to_o describe_v a_o triangle_n and_o this_o be_v to_o be_v note_v that_o every_o proposition_n whether_o it_o be_v a_o problem_n or_o a_o theorem_a common_o contain_v in_o it_o a_o thing_n give_v and_o a_o thing_n require_v to_o be_v search_v out_o although_o it_o be_v not_o always_o so_o and_o the_o thing_n give_v give_v be_v ever_o
side_n the_o rectiline_a angle_n mab_n either_o of_o which_o be_v equal_a to_o the_o rectiline_a angle_n give_v cde_o which_o be_v require_v to_o be_v do_v an_o other_o construction_n also_o and_o demonstration_n after_o pelitar●us_n and_o if_o the_o perpendicular_a line_n chance_n to_o fall_v without_o the_o angle_n give_v namely_o if_o the_o angle_n give_v be_v a_o acute_a angle_n the_o self_n same_o manner_n of_o demonstration_n will_v serve_v but_o only_o that_o in_o stead_n of_o the_o second_o common_a sentence_n must_v be_v use_v the_o 3._o common_a sentence_n appollonius_n put_v another_o construction_n &_o demonstration_n of_o this_o proposition_n which_o though_o the_o demonstration_n thereof_o depend_v of_o proposition_n put_v in_o the_o three_o book_n yet_o for_o that_o the_o construction_n be_v very_o good_a for_o he_o that_o will_v ready_o and_o mechanical_o without_o demonstration_n describe_v upon_o a_o line_n give_v and_o to_o a_o point_n in_o it_o give_v a_o rectiline_a angle_n equal_a to_o a_o rectiline_a angle_n give_v i_o think_v not_o amiss_o here_o to_o place_v it_o and_o it_o be_v thus_o proposition_n oenopides_n be_v the_o first_o inventor_n of_o this_o proposition_n as_o witness_v eudemius_fw-la the_o 15._o theorem_a the_o 24._o proposition_n if_o two_o triangle_n have_v two_o side_n of_o the_o one_o equal_a to_o two_o side_n of_o the_o other_o each_o to_o his_o correspondent_a side_n and_o if_o the_o angle_n contain_v under_o the_o equal_a side_n of_o the_o one_o be_v great_a than_o the_o angle_n contain_v under_o the_o equal_a side_n of_o the_o other_o the_o base_a also_o of_o the_o same_o shall_v be_v great_a than_o the_o base_a of_o the_o other_o svppose_v that_o there_o be_v two_o triangle_n abc_n and_o def_n have_v two_o side_n of_o the_o one_o that_o be_v ab_fw-la and_o ac_fw-la equal_a to_o two_o side_n of_o the_o other_o that_o be_v to_o de_fw-fr and_o df_o each_o to_o his_o correspondent_a side_n that_o be_v the_o side_n ab_fw-la to_o the_o side_n de_fw-fr and_o the_o side_n ac_fw-la to_o the_o side_n df_o and_o suppose_v that_o the_o angle_n bac_n be_v great_a than_o the_o angle_n edf_o then_o i_o say_v that_o the_o base_a bc_o be_v great_a than_o the_o base_a ef._n for_o forasmuch_o as_o the_o angle_n bac_n be_v great_a than_o the_o angle_n edf_o construction_n make_v by_o the_o 23._o proposition_n upon_o the_o right_a line_n de_fw-fr and_o to_o the_o point_n in_o it_o give_v d_o a_o angle_n edge_v equal_a to_o the_o angle_n give_v bac_n and_o to_o one_o of_o these_o line_n that_o be_v either_o to_o ac_fw-la or_o df_o put_v a_o equal_a line_n dg_o and_o by_o the_o first_o petition_n draw_v a_o right_a line_n from_o the_o point_n g_o to_o the_o point_n e_o and_o a_o other_o from_o the_o point_n fletcher_n demonstration_n to_o the_o point_n g._n and_o forasmuch_o as_o the_o line_n ab_fw-la be_v equal_a to_o the_o line_n de_fw-fr and_o the_o line_n ac_fw-la to_o the_o line_n dg_o the_o one_o to_o the_o outstretch_o and_o the_o angle_n bac_n be_v by_o construction_n equal_a to_o the_o angle_n edg_n therefore_o by_o the_o 4._o proposition_n the_o base_a bc_o be_v equal_a to_o the_o base_a eglantine_n again_o for_o as_o much_o as_o the_o line_n dg_o be_v equal_a to_o the_o line_n df_o ther●_n by_o the_o 5._o proposition_n the_o angle_n dgf_n be_v equal_a to_o the_o angle_n dfg_n wherefore_o the_o angle_n dfg_n be_v great_a than_o the_o angle_n egf_n wherefore_o the_o angle_n efg_o be_v much_o great_a than_o the_o angle_n egf_n and_o forasmuch_o as_o efg_o be_v a_o triangle_n have_v the_o angle_n efg_o great_a than_o the_o angle_n egf_n and_o by_o the_o 18._o pr●position_n under_o the_o great_a angle_n be_v subtend_v the_o great_a side_n therefore_o the_o side_n eglantine_n be_v great_a than_o the_o side_n ef._n but_o the_o side_n eglantine_n be_v equal_a to_o the_o side_n bc_o wherefore_o the_o side_n bc_o be_v great_a than_o the_o side_n ef._n if_o therefore_o two_o triangle_n have_v two_o side_n of_o the_o one_o equal_a to_o two_o side_n of_o the_o other_o each_o to_o his_o correspondent_a side_n and_o if_o the_o angle_n contain_v under_o the_o equal_a side_n of_o the_o one_o be_v great_a than_o the_o angle_n contain_v under_o the_o equal_a side_n of_o the_o other_o the_o base_a also_o of_o the_o same_o shall_v be_v great_a than_o the_o base_a of_o the_o other_o which_o be_v require_v to_o be_v prove_v in_o this_o theorem_a may_v be_v three_o case_n pr●position_n for_o the_o angle_n edg_n be_v put_v equal_a to_o the_o angle_n bac_n and_o the_o line_n dg_o be_v put_v equal_a to_o the_o line_n ac_fw-la and_o a_o line_n be_v draw_v from_o e_o to_o g_z the_o line_n eglantine_n shall_v either_o fall_v above_o the_o line_n gf_o or_o upon_o it_o or_o under_o it_o euclides_n demonstration_n serve_v 2._o when_o the_o line_n ge_z fall_v above_o the_o line_n gf_o as_o we_o have_v before_o manifest_o see_v but_o now_o let_v the_o line_n eglantine_n case_n fall_v under_o the_o line_n e_o fletcher_n as_o in_o the_o figure_n here_o put_v and_o forasmuch_o as_o these_o two_o line_n ab_fw-la and_o ac_fw-la be_v equal_a to_o these_o two_o line_n de_fw-fr and_o dg_o the_o one_o to_o the_o other_o and_o they_o contain_v equal_a angle_n therefore_o by_o the_o 4._o proposition_n the_o base_a bc_o be_v equal_a to_o the_o base_a eglantine_n and_o forasmuch_o as_o within_o the_o triangle_n deg_n the_o two_o linne_n df_o and_o fe_o be_v set_v upon_o the_o side_n de_fw-fr therefore_o by_o the_o 21._o proposition_n the_o line_n df_o and_o f●_n be_v less_o than_o the_o outward_a line_n dg_o and_o ge_z but_o the_o line_n dg_o be_v equal_a to_o the_o line_n df._n wherefore_o the_o line_n ge_z be_v great_a than_o the_o line_n fe_o but_o ge_z be_v equal_a to_o bc._n wherefore_o the_o line_n bc_o be_v great_a the_o the_o line_n ef._n which_o be_v require_v to_o be_v prove_v it_o may_v peradventure_o seme●_n that_o euclid_n shall_v here_o in_o this_o proposition_n have_v prove_v that_o not_o only_o the_o base_n of_o the_o triangle_n be_v unequal_a but_o also_o that_o the_o area_n of_o the_o same_o be_v unequal_a for_o so_o in_o the_o four_o proposition_n after_o he_o have_v prove_v the_o base_a to_o be_v equal_a he_o prove_v also_o the_o area_n to_o be_v equal_a but_o hereto_o may_v be_v answer_v &c._a that_o in_o equal_a angle_n and_o base_n and_o unequal_a angle_n and_o base_n the_o consideration_n be_v not_o like_a for_o the_o angle_n and_o base_n be_v equal_a the_o triangle_n also_o shall_v of_o necessity_n be_v equal_a but_o the_o angle_n and_o base_n be_v unequal_a the_o area_n shall_v not_o of_o necessity_n be_v equal_a for_o the_o triangle_n may_v both_o be_v equal_a and_o unequal_a and_o that_o may_v be_v the_o great_a which_o have_v the_o great_a angle_n and_o the_o great_a base_n and_o it_o may_v also_o be_v the_o less_o and_o for_o that_o cause_n euclid_n make_v not_o mention_v of_o the_o comparison_n of_o the_o triangle_n whereof_o this_o also_o may_v be_v a_o cause_n for_o that_o to_o the_o demonstration_n thereof_o be_v require_v certain_a proposition_n concern_v parallel_a line_n which_o we_o be_v not_o as_o yet_o come_v unto_o etc_n howbeit_o after_o the_o 37●_n proposition_n of_o his_o book_n you_o shall_v find_v the_o comparison_n of_o the_o area_n of_o triangle_n which_o have_v their_o side_n equal_a and_o their_o base_n and_o angle_n at_o the_o top_n unequal_a the_o 16._o theorem_a the_o 25._o proposition_n if_o two_o triangle_n have_v two_o side_n of_o the_o one_o equal_a to_o two_o side_n of_o the_o other_o each_o to_o his_o correspondent_a side_n and_o if_o the_o base_a of_o the_o one_o be_v great_a than_o the_o base_a of_o the_o other_o the_o angle_n also_o of_o the_o same_o contain_v under_o the_o equal_a right_a lines●_n shall_v be_v great_a than_o the_o angle_n of_o the_o other_o svppose_v that_o there_o be_v two_o triangle_n a_o b_o c_o and_o def_n have_v two_o side_n of_o tb'one_n that_o be_v ab_fw-la and_o ac_fw-la equal_a to_o two_o side_n of_o the_o other_o that_o be_v to_o de_fw-fr and_o df_o each_o to_o his_o correspondent_a side_n namely_o the_o side_n ab_fw-la to_o the_o side_n df_o and_o the_o side_n ac_fw-la to_o the_o side_n df._n but_o let_v the_o base_a bc_o be_v great_a than_o the_o base_a ef._n then_o i_o say_v they_o the_o angle_n bac_n be_v great_a than_o the_o angle_n edf_o for_o if_o not_o absurdity_n then_o be_v it_o either_o equal_a unto_o it_o or_o less_o than_o it_o but_o the_o angle_n bac_n be_v not_o equal_a to_o the_o angle_n edf_o for_o if_o it_o be_v equal_a the_o base_a also_o bc_o shall_v by_o the_o 4._o proposition_n be_v equal_a to_o the_o base_a of_o but_o by_o supposition_n it_o be_v not_o wherefore_o
namely_o the_o first_o ten_o proposition_n as_o they_o follow_v in_o order_n which_o be_v undoubted_o great_a pleasure_n to_o consider_v also_o great_a increase_n &_o furniture_n of_o knowledge_n who_o proposition_n be_v set_v orderly_a after_o the_o proposition_n of_o euclid_n every_o one_o of_o barlaam_n correspondent_a to_o the_o same_o of_o euclid_n and_o doubtless_o it_o be_v wonderful_a to_o see_v how_o these_o two_o contrary_a kind_n of_o quantity_n quantity_n discrete_a or_o number_n and_o quantity_n continual_a or_o magnitude_n which_o be_v the_o subject_n or_o matter●_n of_o arithmitique_a and_o geometry_n shall_v have_v in_o they_o one_o and_o the_o same_o propriety_n common_a to_o they_o both_o in_o very_a many_o point_n and_o affection_n although_o not_o in_o all_o for_o a_o line_n may_v in_o such_o sort_n be_v divide_v that_o what_o proportion_n the_o whole_a have_v to_o the_o great_a part_n the_o same_o shall_v the_o great_a part_n have_v to_o the_o less_o but_o that_o can_v not_o be_v in_o number_n for_o a_o number_n can_v not_o so_o be_v divide_v that_o the_o whole_a number_n to_o the_o great_a part_n thereof_o shall_v have_v that_o proportion_n which_o the_o great_a part_n have_v to_o the_o less_o as_o jordane_n very_o plain_o prove_v in_o his_o book_n of_o arithmetic_n which_o thing_n campane_n also_o as_o we_o shall_v afterward_o in_o the_o 9_o book_n after_o the_o 15._o proposition_n see_v prove_v and_o as_o touch_v these_o ten_o first_o proposition_n of_o the_o second_o book_n of_o euclid_n demonstrate_v by_o barlaam_n in_o number_n they_o be_v also_o demonstrate_v of_o campane_n after_o the_o 15._o proposition_n of_o the_o 9_o book_n who_o demonstration_n i_o mind_n by_o god_n help_n to_o set_v forth_o when_o i_o shall_v come_v to_o the_o place_n they_o be_v also_o demonstrate_v of_o jordane_n that_o excellet_fw-la learned_a author_n in_o the_o first_o book_n of_o his_o arithmetic_n in_o the_o mean_a time_n i_o think_v it_o not_o amiss_o here_o to_o set_v forth_o the_o demonstration_n of_o barlaam_n for_o that_o they_o geve_v great_a light_n to_o the_o second_o book_n of_o euclid_n beside_o the_o inestimable_a pleasure_n which_o they_o bring_v to_o the_o studious_a considerer_n and_o now_o to_o declare_v the_o first_o proposition_n by_o number_n i_o have_v put_v this_o example_n follow_v take_v two_o number_n the_o one_o undivided_a as_o 74._o the_o other_o divide_v into_o what_o part_n and_o how_o many_o you_o listen_v as_o 37._o divide_v into_o 20._o 10._o 5._o and_o 2d_o which_o altogether_o make_v the_o whole_a 37._o then_o if_o you_o multiply_v the_o number_n undivided_a namely_o 74_o into_o all_o the_o part_n of_o the_o number_n divide_v as_o into_o 20._o 10._o 5._o and_o 2._o you_o shall_v produce_v 1480._o 740._o 370._o 148._o which_o add_v together_o make_v 2738_o which_o self_n number_n be_v also_o produce_v if_o you_o multiply_v the_o two_o number_n first_o give_v the_o one_o into_o the_o other_o as_o you_o see_v in_o the_o example_n on_o the_o other_o side_n set_v so_o by_o the_o aid_n of_o this_o proposition_n be_v get_v a_o compendious_a way_n of_o multiplication_n by_o break_v of_o one_o of_o the_o number_n into_o his_o part_n which_o oftentimes_o serve_v to_o great_a use_n in_o working_n chi●●ly_o in_o the_o rule_n of_o proportion_n the_o demonstration_n of_o which_o proposition_n follow_v in_o barlaam_n but_o ●irst_n be_v put_v of_o the_o author_n these_o principle_n follow_v barlaam_n ¶_o principles_n 1._o a_o number_n be_v s●yd_v to_o multiply_v a_o other_o number_n when_o the_o number_n multiply_v be_v so_o oftentimes_o add_v to_o itself_o as_o there_o be_v unity_n in_o the_o number_n which_o multiply_v whereby_o be_v produce_v a_o certain_a number_n which_o the_o number_n multiply_v measure_v by_o the_o unity_n which_o be_v in_o the_o number_n which_o multipli_v 2._o and_o the_o number_n produce_v of_o that_o a_o multiplication_n be_v call_v a_o plain_a or_o superficial_a number_n 3._o a_o square_a number_n be_v that_o which_o be_v produce_v of_o the_o multiplicatian_n of_o any_o number_n into_o itself_o 4._o every_o less_o number_n compare_v to_o a_o great_a be_v say_v to_o be_v a_o part_n of_o the_o great_a whether_o the_o less_o measure_n the_o great_a or_o measure_v it_o not_o 5._o number_n who_o one_o and_o the_o self_n same_o number_n measure_v equal_o that_o be_v by_o one_o and_o the_o self_n same_o number_n be_v equal_a the_o one_o to_o the_o other_o 6._o number_n that_o be_v equemultipl●ces_n to_o one_o and_o the_o self_n same_o number_n that_o be_v which_o contain_v one_o and_o the_o same_o number_n equal_o and_o alike_o be_v equal_a the_o one_o to_o the_o other_o the_o first_o proposition_n two_o number_n be_v give_v if_o the_o one_o of_o they_o be_v divide_v into_o any_o number_n how_o many_o soever_o barlaam_n the_o plain_n or_o superficial_a number_n which_o be_v produce_v of_o the_o multiplication_n of_o the_o two_o number_n first_o give_v the_o one_o into_o the_o other_o shall_v be_v equal_a to_o the_o superficial_a number_n which_o be_v produce_v of_o the_o multiplication_n of_o the_o number_n not_o divide_v into_o every_o part_n of_o the_o number_n divide_v suppose_v that_o there_o be_v two_o number_n ab_fw-la and_o c._n and_o divide_v the_o number_n ab_fw-la into_o certain_a other_o number_n how_o many_o soever_o as_o into_o ad_fw-la de_fw-fr and_o ebb_v then_o i_o say_v that_o the_o superficial_a number_n which_o be_v produce_v of_o the_o multiplication_n of_o the_o number_n c_o into_o the_o number_n ab_fw-la be_v equal_a to_o the_o superficial_a number_n which_o be_v produce_v of_o the_o multiplication_n of_o the_o number_n c_o into_o the_o number_n ad_fw-la and_o of_o c_o into_o de_fw-fr and_o of_o c_o into_o ebb_n for_o let_v fletcher_n be_v the_o superficial_a number_n produce_v of_o the_o multiplication_n of_o the_o number_n c_o into_o the_o number_n ab_fw-la and_o let_v gh_o be_v the_o superficial_a number_n produce_v of_o the_o multiplication_n of_o c_o into_o ad_fw-la and_o let_v high_a be_v produce_v of_o the_o multiplication_n of_o c_o into_o de_fw-fr a●d_v final_o of_o the_o multiplication_n of_o c_o into_o ebb_n let_v there_o be_v produce_v the_o number_n ik_fw-mi now_o forasmuch_o as_o ab_fw-la multiply_v the_o number_n c_o produce_v the_o number_n f_o therefore_o the_o number_n c_o measure_v the_o number_n f_o by_o the_o unity_n which_o be_v in_o the_o number_n ab_fw-la and_o by_o the_o same_o reason_n may_v be_v prove_v that_o the_o number_n c_o do_v also_o measure_v the_o number_n gh_o by_o the_o unity_n which_o be_v in_o the_o number_n ad_fw-la and_o that_o it_o do_v measure_v the_o number_n high_a by_o the_o unity_n which_o be_v in_o the_o number_n df_o and_o final_o that_o it_o measure_v the_o number_n ik_fw-mi by_o the_o unity_n which_o be_v in_o the_o number_n ebb_n wherefore_o the_o number_n c_o measure_v the_o whole_a number_n gk_o by_o the_o unity_n which_o be_v in_o the_o number_n ab_fw-la but_o it_o before_o measure_v the_o number_n f_o by_o the_o unity_n which_o be_v in_o the_o number_n ab_fw-la wherefore_o either_o of_o these_o number_n fletcher_n and_o gk_o be_v equemultiplex_n to_o the_o number_n c._n but_o number_n which_o be_v equemultiplices_fw-la to_o one_o &_o the_o self_n same_o number_n be_v equal_a the_o one_o to_o the_o other_o by_o the_o 6._o definition_n wherefore_o the_o number_n fletcher_n be_v equal_a to_o the_o number_n gk_o but_o the_o number_n fletcher_n be_v the_o superficial_a number_n produce_v of_o the_o multiplication_n of_o the_o number_n c_o into_o the_o number_n ab_fw-la and_o the_o number_n gk_o be_v compose_v of_o the_o superficial_a number_n produce_v of_o the_o multiplication_n of_o the_o number_n c_o not_o divide_v into_o every_o one_o of_o the_o number_n ad_fw-la de_fw-fr and_o ebb_v if_o therefore_o there_o be_v two_o number_n give_v and_o the_o one_o of_o they_o be_v divide_v etc_n etc_n which_o be_v require_v to_o be_v prove_v the_o 2._o theorem_a the_o 2._o proposition_n if_o a_o right_a line_n be_v divide_v by_o chance_n the_o rectangle_v figure_n which_o be_v comprehend_v under_o the_o whole_a and_o every_o one_o of_o the_o part_n be_v equal_a to_o the_o square_n which_o be_v make_v of_o the_o whole_a svppose_v that_o the_o right_a line_n ab_fw-la be_v by_o chance_n deny_v in_o the_o point_n c._n then_o i_o say_v that_o the_o rectangle_n figure_n comprehend_v under_o ab_fw-la and_o bc_o together_o with_o the_o rectangle_n comprehend_v under_o ab_fw-la and_o ac_fw-la be_v equal_a unto_o the_o square_n make_v of_o ab_fw-la construction_n describe_v by_o the_o 46._o of_o the_o first_o upon_o ab_fw-la a_o square_a adeb_n and_o by_o the_o 31_o of_o the_o first_o by_o the_o point_n c_o draw_v a_o line_n parallel_n unto_o either_o of_o these_o line_n ad_fw-la a●d_fw-la be_v and_o let_v the_o same_o
number_n of_o the_o number_n ad_fw-la and_o db_o be_v double_a to_o the_o square_a number_n of_o ac_fw-la and_o cd_o for_o forasmuch_o as_o the_o number_n ad_fw-la be_v divide_v into_o the_o number_n ab_fw-la and_o bd_o therefore_o the_o square_a number_n of_o the_o number_n ad_fw-la and_o db_o be_v equal_a to_o the_o superficial_a number_n produce_v of_o the_o multiplication_n of_o the_o number_n ad_fw-la and_o db_o the_o on_o into_o the_o other_o twice_o together_o with_o the_o square_n of_o the_o number_n ab_fw-la by_o the_o 7_o proposition_n but_o the_o square_n of_o the_o number_n ab_fw-la be_v equal_a to_o four_o square_n of_o either_o of_o the_o number_n ac_fw-la or_o cb_o for_o ac_fw-la be_v equal_a to_o the_o number_n cb_o wherefore_o also_o the_o square_n of_o the_o number_n ad_fw-la and_o db_o be_v equal_a to_o the_o superficial_a number_n produce_v of_o the_o multiplication_n of_o the_o number_n ad_fw-la and_o db_o the_o one_o into_o the_o other_o twice_o and_o to_o four_o square_n of_o the_o number_n bc_o or_o ca._n and_o forasmuch_o as_o the_o superficial_a number_n produce_v of_o the_o multiplication_n of_o the_o number_n ad_fw-la and_o db_o the_o one_o into_o the_o other_o together_o with_o the_o square_n of_o the_o number_n cb_o be_v equal_a to_o square_v of_o the_o number_n cd_o by_o the_o 6_o proposition_n therefore_o the_o number_n produce_v of_o the_o multiplication_n of_o the_o number_n ad_fw-la and_o db_o the_o one_o into_o the_o other_o twice_o together_o with_o two_o square_n of_o the_o number_n cb_o be_v equal_a to_o two_o square_n of_o the_o number_n cd_o wherefore_o the_o square_n of_o the_o number_n ad_fw-la and_o db_o be_v equal_a to_o two_o square_n of_o the_o number_n cd_o and_o to_o two_o square_n of_o the_o number_n ac_fw-la wherefore_o they_o be_v double_a to_o the_o square_n of_o the_o number_n ac_fw-la and_o cd_o and_o the_o square_a of_o the_o number_n ad_fw-la be_v the_o square_n of_o the_o whole_a and_o of_o the_o number_n add_v and_o the_o square_a of_o db_o be_v the_o square_a of_o the_o number_n add_v the_o square_a also_o of_o the_o number_n cd_o be_v the_o square_a of_o the_o number_n compose_v of_o the_o half_a and_o of_o the_o number_n add_v if_o therefore_o a_o even_a number_n be_v divide_v etc_n etc_n which_o be_v require_v to_o be_v prove_v the_o 1._o problem_n the_o 11._o proposition_n to_o divide_v a_o right_a line_n give_v in_o such_o sort_n that_o the_o rectangle_n figure_n comprehend_v under_o the_o whole_a and_o one_o of_o the_o part_n shall_v be_v equal_a unto_o the_o square_n make_v of_o the_o other_o part_n svppose_v that_o the_o right_a line_n give_v be_v ab_fw-la now_o it_o be_v require_v to_o divide_v the_o line_n ab_fw-la in_o such_o sort_n that_o the_o rectangle_n figure_n contain_v under_o the_o whole_a and_o one_o of_o the_o part_n shall_v be_v equal_a unto_o the_o square_n which_o be_v make_v of_o the_o other_o part_n describe_v by_o the_o 46._o of_o the_o first_o upon_o ab_fw-la a_o square_a abcd._n construction_n and_o by_o the_o 10._o of_o the_o first_o divide_v the_o line_n ac_fw-la into_o two_o equal_a part_n in_o the_o point_n e_o and_o draw_v a_o line_n from_o b_o to_o e._n and_o by_o the_o second_o petition_n extend_v ca_n unto_o the_o point_n f._n and_o by_o the_o 3._o of_o the_o first_o put_v the_o line_n of_o equal_a unto_o the_o line_n be._n and_o by_o the_o 46._o of_o the_o first_o upon_o the_o line_n of_o describe_v a_o square_a fgah_n and_o by_o the_o 2._o petition_n extend_v gh_o unto_o the_o point_n k._n then_o i_o say_v that_o the_o line_n ab_fw-la be_v divide_v in_o the_o point_n h_o in_o such_o sort_n that_o the_o rectangle_n figure_n which_o be_v comprehend_v under_o ab_fw-la and_o bh_o be_v equal_a to_o the_o square_n which_o be_v make_v of_o ah_o demonstration_n for_o forasmuch_o as_o the_o right_a line_n ac_fw-la be_v divide_v into_o two_o equal_a part_n in_o the_o point_n e_o and_o unto_o it_o be_v add_v a_o other_o right_a line_n af._n therefore_o by_o the_o 6._o of_o the_o second_o the_o rectangle_n figure_n contain_v under_o cf_o and_o favorina_n together_o with_o the_o square_n which_o be_v make_v of_o ae_n be_v equal_a to_o the_o square_v which_o be_v make_v of_o ef._n but_o of_o be_v equal_a unto_o ebb_n wherefore_o the_o rectangle_n figure_n contain_v under_o cf_o and_o favorina_n together_o with_o the_o square_n which_o be_v make_v of_o ea_fw-la be_v equal_a to_o the_o square_n which_o be_v make_v of_o ebb_n but_o by_o 47._o of_o the_o first_o unto_o the_o square_n which_o be_v make_v of_o ebb_n be_v equal_a the_o square_n which_o be_v make_v of_o basilius_n and_o ae_n for_o the_o angle_n at_o the_o point_n a_o be_v a_o right_a angle_n wherefore_o that_o which_o be_v contain_v under_o cf_o and_o favorina_n together_o with_o the_o square_n which_o be_v make_v of_o ae_n be_v equal_a to_o the_o square_n which_o be_v make_v of_o basilius_n and_o ae_n take_v away_o the_o square_n which_o be_v make_v of_o ae_n which_o be_v common_a to_o they_o both_o wherefore_o the_o rectangle_n figure_n remain_v contain_v under_o cf_o and_o favorina_n be_v equal_a unto_o the_o square_n which_o be_v make_v of_o ab_fw-la and_o that_o which_o be_v contain_v under_o the_o line_n cf_o and_o favorina_n be_v the_o figure_n fk_o for_o the_o line_n favorina_n be_v equal_a unto_o the_o line_n fg._n and_o the_o square_n which_o be_v make_v of_o ab_fw-la be_v the_o figure_n ad._n wherefore_o the_o figure_n fk_o be_v equal_a unto_o the_o figure_n ad._n take_v away_o the_o figure_n ak_o which_o be_v common_a to_o they_o both_o wherefore_o the_o residue_n namely_o the_o figure_n fh_o be_v equal_a unto_o the_o residue_n namely_o unto_o the_o figure_n hd_v but_o the_o figure_n hd_v be_v that_o which_o be_v contain_v under_o the_o line_n ab_fw-la and_o bh_o for_o ab_fw-la be_v equal_a unto_o bd._n and_o the_o figure_n fh_o be_v the_o square_n which_o be_v make_v of_o ah_o wherefore_o the_o rectangle_n figure_n comprehend_v under_o the_o line_n ab_fw-la and_o bh_o be_v equal_a to_o the_o square_n which_o be_v make_v of_o the_o line_n ha._n wherefore_o the_o right_a line_n give_v ab_fw-la be_v divide_v in_o the_o point_n h_o in_o such_o sort_n that_o the_o rectangle_n figure_n contain_v under_o ab_fw-la and_o bh_o be_v equal_a to_o the_o square_n which_o be_v make_v of_o ah_o which_o be_v require_v to_o be_v do_v this_o proposition_n have_v many_o singular_a use_n upon_o it_o depend_v the_o demonstration_n of_o that_o worthy_a problem_n the_o 10._o proposition_n of_o the_o 4._o book_n proposition_n which_o teach_v to_o describe_v a_o isosceles_a triangle_n in_o which_o either_o of_o the_o angle_n at_o the_o base_a shall_v be_v double_a to_o the_o angle_n at_o the_o top_n many_o and_o diverse_a use_n of_o a_o line_n so_o divide_v shall_v you_o find_v in_o the_o 13._o book_n of_o euclid_n this_o be_v to_o be_v note_v that_o this_o proposition_n can_v not_o as_o the_o former_a proposition_n of_o this_o second_o book_n be_v reduce_v unto_o number_n number_n for_o the_o line_n ebb_n have_v unto_o the_o line_n ae_n no_o proportion_n that_o can_v be_v name_v and_o therefore_o it_o can_v not_o be_v express_v by_o number_n for_o forasmuch_o as_o the_o square_n of_o ebb_n be_v equal_a to_o the_o two_o square_n of_o ab_fw-la and_o ae_n by_o the_o 47._o of_o the_o first_o and_o ae_n be_v the_o half_a of_o ab_fw-la therefore_o the_o line_n be_v be_v irrational_a for_o even_o as_o two_o equal_a square_a number_n join_v together_o can_v not_o make_v a_o square_a number_n so_o also_o two_o square_a number_n of_o which_o the_o one_o be_v the_o square_a of_o the_o half_a root_n of_o the_o other_o can_v not_o make_v a_o square_a number_n as_o by_o a_o example_n take_v the_o square_n of_o 8._o which_o be_v 64._o which_o double_v that_o be_v 128._o make_v not_o a_o square_a number_n so_o take_v the_o half_a of_o 8._o which_o be_v 4._o and_o the_o square_n of_o 8._o and_o 4._o which_o be_v 64._o and_o 16._o add_v together_o likewise_o make_v not_o a_o square_a number_n for_o they_o make_v 80._o who_o have_v no_o root_n square_v which_o thing_n must_v of_o necessity_n be_v if_o this_o problem_n shall_v have_v place_n in_o number_n but_o in_o irrational_a number_n it_o be_v true_a and_o may_v by_o this_o example_n be_v declare_v let_v 8._o be_v so_o divide_v that_o that_o which_o be_v produce_v of_o the_o whole_a into_o one_o of_o his_o part_n shall_v be_v equal_a to_o the_o square_a number_n produce_v of_o the_o other_o part_n multiply_v 8._o into_o himself_o and_o there_o shall_v be_v produce_v 64._o that_o be_v the_o square_a abcd._n divide_v 8._o into_o two_o equal_a part_n that_o be_v into_o 4_o and_o 4._o as_o the_o line_n
&_o m._n demonstration●_n if_o therefore_o g_z exceed_v l_o then_z also_o h_o exceed_v m_o and_o if_o it_o be_v equal_a it_o be_v equal_a and_o if_o it_o be_v less_o it_o be_v less_o by_o the_o converse_n of_o the_o 6●_o definition_n of_o the_o five_o again_o because_o that_o as_o c_o be_v to_o d_z so_o be_v e_o to_o fletcher_n and_o to_o c_o and_o e_o be_v take_v ●●●em●ltiplices_n h_o ●●d_z king_n and_o likewise_o to_o d_z &_o f_o be_v take_v certain_a other_o equemultiplices_fw-la m_o &_o n._n if_o therefore_o h_o exceed_v m_o than_o also_o king_n exceed_v n_o and_o if_o it_o be_v equal_a it_o be_v equal_a and_o if_o it_o be_v less_o it_o be_v less_o by_o the_o same_o converse_n but_o if_o king_n exceed_v m_o than_o also_o g_z exceed_v l_o and_o if_o it_o be_v equal_a it_o be_v equal_a and_o if_o it_o be_v less_o it_o be_v less_o by_o the_o same_o converse_n wherefore_o if_o g_z exceed_v l_o then_z king_n also_o exceed_v n_o and_o if_o it_o be_v equal_a it_o be_v equal_a and_o if_o it_o be_v less_o it_o be_v less_o but_o g_z &_o king_n be_v equemultiplices_fw-la of_o a_o &_o e._n and_o l_o &_o n_o be_v certain_a other_o equemultiplices_fw-la of_o b_o &_o f._n wherefore_o by_o the_o 6._o definition_n as_o a_o be_v to_o b_o so_o be_v e_o to_o f._n proportion_n therefore_o which_o be_v one_o and_o the_o self_n same_o to_o any_o one_o proportion_n be_v also_o the_o self_n same_o one_o to_o the_o other_o which_o be_v require_v to_o be_v prove_v the_o 12._o theorem_a the_o 12._o proposition_n if_o there_o be_v a_o number_n of_o magnitude_n how_o many_o soe●●r_n proportional_a as_o one_o of_o the_o antecedentes_fw-la be_v to_o one_o of_o the_o consequentes_fw-la so_o be_v all_o the_o antecedentes_fw-la to_o all_o the_o consequentes_fw-la svppose_v that_o there_o be_v a_o number_n of_o magnitude_n how_o many_o soever_o namely_o a_o b_o c_o d_o e_o f_o in_o proportion_n so_o that_o as_o a_o be_v to_o b_o so_o let_v c_o be_v to_o d_o and_o e_o to_o f._n then_o i_o say_v that_o as_o a_o be_v to_o b_o so_o 〈◊〉_d a_o c_o e_o to_o b_o d_o f._n take_v equemultiplices_fw-la to_o a_o c_o and_o e._n constr●ction_n and_o let_v the_o same_o be_v g_o h_o k._n and_o likewise_o to_o b_o d_o and_o fletcher_n ●ake_z any_o other_o equemultiplices_fw-la which_o to_o be_v l_o m_o n._n and_o because_o that_o 〈◊〉_d a_o be_v to_o b_o so_o i●_z c_o to_o d_z and_o e_o to_o f._n demonstration●_n and_o to_o a_o c_o e_o be_v take_v ●quemultiplices_n g_o h_o king_n and_o likewise_o to_o ●_o d_o f_o be_v take_v certain_a other_o equem●●tipli●●s_n l_o m_o n._n if_o therefore_o g_z exceed_v l_o h_o also_o exceed_v m_o and_o kn_n and_o if_o it_o be_v equal_a it_o be_v equal_a and_o if_o it_o be_v less_o it_o be_v less_o ●y_a the_o converse_n of_o the_o six●_o definition_n of_o the_o five_o wherefore_o if_o g_z exceed_v l_o then_z g_z h_o edward_n also_o exceed_v l_o m_o n_o and_o if_o they_o be_v equal_a they_o be_v equal_a and_o if_o they_o be_v less_o they_o be_v less_o by_o the_o same_o but_o g_z and_o g_z h_o edward_n be_v equemultiplices_fw-la to_o the_o magnitude_n a_o and_o to_o the_o magnitude_n a_o c_o e._n for_o by_o the_o first_o of_o the_o five_o if_o there_o be_v a_o number_n of_o magnitude_n equemultiplices_fw-la to_o a_o like_a number_n of_o magnitude_n each_o to_o each_o how_o multiplex_n one_o magnitude_n be_v to_o one_o so_o multiplices_fw-la be_v all_o the_o magnitude_n to_o all_o and_o by_o the_o same_o reason_n also_o l_o and_o l_o m_o n_o be_v equemultiplices_fw-la to_o the_o magnitude_n b_o and_o to_o the_o magnitude_n b_o d_o f_o wherefore_o as_o a_o be_v to_o b_o so_o be_v a_o c_o e_o to_o b_o d_o f_o by_o the_o six_o definition_n of_o the_o five_o if_o therefore_o there_o be_v a_o number_n of_o magnitude_n how_o many_o soever_o proportional_a as_o one_o of_o the_o antecedentes_fw-la be_v to_o one_o of_o the_o consequentes_fw-la so_o be_v all_o the_o antecedentes_fw-la to_o all_o the_o consequentes_fw-la which_o be_v require_v to_o be_v prove_v the_o 13._o theorem_a the_o 13._o proposition_n if_o the_o first_o have_v unto_o the_o second_o the_o self_n same_o proportion_n that_o the_o three_o have_v to_o the_o four_o and_o if_o the_o three_o have_v unto_o the_o four_o a_o great_a proportion_n they_o the_o five_o have_v to_o the_o six_o they_o shall_v the_o first_o also_o have_v unto_o the_o second_o a_o great_a proportion_n than_o have_v the_o five_o to_o the_o six_o svppose_v that_o there_o be_v six_o magnitude_n of_o which_o let_v a_o be_v the_o first_o b_o the_o second_o c_o the_o three_o d_z the_o four_o e_o the_o five_o and_o fletcher_n the_o six_o suppose_v that_o a_o the_o first_o have_v unto_o b_o the_o second_o the_o self_n same_o proportion_n that_o c_o the_o three_o have_v to_o d_o the_o four_o and_o let_v c_o the_fw-fr three_o have_v unto_o d_z the_o four_o a_o great_a proportion_n than_o have_v e_o the_o five_o to_o f_o the_o six_o then_o i_o say_v that_o a_o the_o first_o have_v to_o b_o the_o second_o a_o great_a proportion_n then_o have_v e_o the_o five_o to_o f_o the_o six_o construction_n for_o forasmuch_o as_o c_z have_v to_o d_z a_o great_a proportion_n than_o have_v e_o to_o fletcher_n therefore_o there_o be_v certain_a equemultiplices_fw-la to_o c_o and_o e_o and_o likewise_o any_o other_o equemultiplices_fw-la whatsoever_o to_o d_z and_o f_o which_o be_v compare_v together_o the_o multiplex_n to_o c_o shall_v exceed_v the_o multiplex_n to_o d_o but_o the_o multiplex_n to_o e_o shall_v not_o exceed_v the_o multiplex_n to_o fletcher_n by_o the_o converse_n of_o the_o eight_o definition_n of_o this_o book_n let_v those_o multiplices_fw-la be_v take_v and_o suppose_v that_o the_o equemultiplices_fw-la to_o c_o and_o e_o be_v g_z and_o h_o and_o likewise_o to_o d_z and_o f_o take_v any_o other_o equemultiplices_fw-la whatsoever_o and_o let_v the_o same_o be_v king_n and_o l_o so_fw-mi that_o let_v g_z exceed_v king_n but_o let_v not_o h_o exceed_v l._n and_o how_o multiplex_n g_z be_v to_o c_o so_o multiplex_n let_v m_o be_v to_o a._n and_o how_o multiplex_n king_n be_v to_o d_o so_o multiplex_n also_o let_v n_o be_v to_o b._n and_o because_o that_o as_o a_o be_v to_o b_o so_o be_v c_z to_o d_z and_o to_o a_o and_o c_o be_v take_v equemultiplices_fw-la m_o and_o g._n demonstration_n and_o likewise_o to_o b_o and_o d_o be_v take_v certain_a other_o equemultiplices_fw-la n_o &_o king_n if_o therefore_o m_o exceed_v n_o g_o also_o exceed_v king_n and_o if_o it_o be_v equal_a it_o be_v equal_a and_o if_o it_o be_v less_o it_o be_v less_o by_o the_o conversion_n of_o the_o six_o definition_n of_o the_o five_o but_o by_o construction_n g_o excedet●_n edward_n wherefore_o m_o also_o exceed_v n_o but_o h_o exceed_v not_o l._n but_o m_o &_o h_o be_v equemultiplices_fw-la to_o a_o &_o e_o and_o n_o &_o l_o be_v certain_a other_o equemultiplices●_n whatsoever_o to_o b_o and_o f._n wherefore_o a_o have_v unto_o b_o a_o great_a proportion_n than_o e_o have_v to_o fletcher_n by_o the_o 8._o definition_n if_o therefore_o the_o first_o have_v unto_o the_o second_o the_o self_n same_o proportion_n that_o the_o three_o have_v to_o the_o four_o and_o if_o the_o three_o have_v unto_o the_o four_o a_o great_a proportion_n than_o the_o five_o have_v to_o the_o six_o then_o shall_v the_o firs●_o also_o have_v unto_o the_o second_o a_o great_a proportion_n than_o have_v the_o 〈◊〉_d to_o the_o sixths_n which_o be_v require_v to_o be_v prove_v ¶_o a_o addition_n of_o campane_n if_o there_o be_v four_o quantity_n campane_n and_o if_o the_o first_o have_v unto_o the_o second_o a_o great_a proportion_n they_o have_v the_o three_o to_o the_o four_o then_o shall_v there_o be_v some_o equemultiplices_fw-la of_o the_o first_o and_o the_o three_o which_o be_v compare_v to_o some_o equemultiplices_fw-la of_o the_o second_o and_o the_o four_o the_o multiplex_n of_o the_o first_o shall_v be_v great_a than_o the_o multiplex_n of_o the_o second_o but_o the_o multiplex_n of_o the_o three_o shall_v not_o be_v great_a than_o the_o multiplex_n of_o the_o four_o although_o this_o proposition_n here_o put_v by_o campane_n need_v no_o demonstration_n for_o that_o it_o be_v but_o the_o converse_n of_o the_o 8._o definition_n of_o this_o book_n yet_o think_v i_o it_o not_o worthy_a to_o be_v omit_v for_o that_o it_o reach_v the_o way_n to_o find_v out_o such_o equemultiplices_fw-la that_o the_o multiplex_n of_o the_o first_o shall_v exceed_v the_o multiplex_n of_o the_o second_o but_o the_o multiplex_n of_o the_o three_o shall_v not_o exceed_v the_o multiplex_n of_o the_o four_o the_o 14._o theorem_a the_o 14
therefore_o alternate_o as_o ab_fw-la be_v to_o e_o so_o be_v cd_o to_o fletcher_n by_o the_o 16._o of_o the_o five_o but_o ab_fw-la be_v great_a than_o e_o wherefore_o also_o cd_o be_v great_a than_o fletcher_n which_o thing_n may_v also_o be_v prove_v by_o the_o 14._o of_o the_o same_o now_o for_o that_o as_o ab_fw-la be_v to_o cd_o so_o be_v e_o to_o fletcher_n but_o e_o be_v equal_a unto_o agnostus_n and_o fletcher_n be_v equal_a unto_o change_z therefore_o as_o ab_fw-la be_v to_o cd_o so_o be_v ag_z to_o change_z and_o forasmuch_o as_o the_o whole_a ab_fw-la be_v to_o the_o whole_a cd_o so_o be_v the_o part_n take_v away_o agnostus_n to_o the_o part_n take_v away_o change_z therefore_o the_o residue_n gb_o by_o the_o 1●_o of_o the_o five_o be_v unto_o the_o residue_n hd_v as_o the_o whole_a ab_fw-la be_v to_o the_o whole_a cd_o but_o ab_fw-la the_o first_o be_v great_a than_o cd_o the_o three_o wherefore_o gb_o the_o second_o be_v great_a than_o hd_v the_o four_o by_o the_o 14._o of_o the_o five_o and_o forasmuch_o as_o agnostus_n be_v equal_a unto_o e_o &_o change_z be_v equal_a unto_o fletcher_n therefore_o agnostus_n and_o fletcher_n be_v equal_a unto_o ch_n and_o e._n and_o forasmuch_o as_o if_o unto_o thing_n unequal_a be_v add_v thing_n equal_a all_o shall_v be_v unequal_a by_o the_o four_o common_a sentence_n therefore_o see_v that_o gb_o and_o dh_o be_v unequal_a and_o gb_o be_v the_o great_a if_o unto_o gb_o be_v add_v agnostus_n and_o fletcher_n and_o likewise_o if_o unto_o hd_n be_v add_v change_z &_o e_o there_o shall_v be_v produce_v ab_fw-la and_o fletcher_n great_a than_o cd_o &_o e._n if_o therefore_o there_o be_v four_o magnitude_n proportional_a the_o great_a and_o the_o least_o of_o they_o shall_v be_v great_a they_o the_o other_o remain_v which_o be_v require_v to_o be_v demonstrate_v here_o follow_v certain_a proposition_n add_v by_o campane_n which_o be_v not_o to_o be_v contemn_v and_o be_v cite_v even_o of_o the_o best_a learned_a namely_o of_o johannes_n regio_fw-la montanus_fw-la in_o the_o epitome_n which_o he_o write_v upon_o ptolemy_n ¶_o the_o first_o proposition_n if_o there_o be_v four_o quantity_n and_o if_o the_o proportion_n of_o the_o first_o to_o the_o second_o be_v great_a than_o the_o proportion_n of_o the_o three_o to_o the_o four_o then_o contrariwise_o by_o conversion_n the_o proportion_n of_o the_o second_o to_o the_o first_o shall_v be_v less_o than_o the_o proportion_n of_o the_o four_o to_o the_o three_o affirmative_o it_o may_v also_o be_v demonstrate_v direct_o for_o let_v e_o be_v unto_o b_o as_z c_z be_v to_o d._n then_o converse_o b_o be_v to_o e_o as_z d_z be_v to_o c._n and_o forasmuch_o as_o a_o be_v great_a than_o e_o by_o the_o first_o part_n of_o the_o ten_o of_o this_o book_n therefore_o by_o the_o second_o part_n of_o the_o 8_o of_o the_o same_o b_o have_v unto_o a_o a_o less_o proportion_n than_o have_v b_o to_o e._n wherefore_o by_o the_o 13._o of_o the_o same_o b_o have_v unto_o a●_n ●_z less_o proportion_n than_o have_v d_z to_o c_z which_o be_v require_v to_o be_v prove_v ¶_o the_o second_o proposition_n if_o there_o be_v four_o quantity_n and_o if_o the_o proportion_n of_o the_o first_o to_o the_o second_o be_v great_a than_o the_o proportion_n of_o the_o three_o to_o the_o four_o then_o alternate_o the_o proportion_n of_o the_o first_o to_o the_o three_o shall_v be_v great_a than_o the_o proportion_n of_o the_o second_o to_o the_o four_o affirmative_o this_o may_v also_o be_v demonstrate_v affirmative_o let_v e_o be_v unto_o b_o as_z c_z be_v to_o d._n now_o they_o by_o the_o first_o part_n of_o the_o ten_o of_o this_o book_n e_o be_v less_o than_o a_o wherefore_o by_o the_o first_o part_n of_o the_o 8._o of_o the_o same_o the_o proportion_n of_o a_o to_o c_o be_v great_a than_o the_o proportion_n of_o e_o to_o c._n but_o alternate_o e_o be_v to_o c_o as_z b_o be_v to_o d._n wherefore_o by_o the_o 13._o of_o the_o same_o a_o have_v to_o c_o a_o 〈…〉_o ¶_o the_o three_o proposition_n if_o there_o be_v four_o quantity_n and_o if_o the_o proportion_n of_o the_o first_o t●_n the_o second_o be_v great_a than_o the_o proportion_n of_o the_o three_o to_o the_o four_o then_o by_o composition_n also_o the_o proportion_n of_o the_o f●●th_n and_o second_v to_o the_o second_o shall_v be_v great_a than_o the_o proportion_n of_o the_o three_o and_o fourth●_o to_o the_o four_o this_o may_v also_o be_v demonstrate_v affirmative_o same_o forasmuch_o as_o the_o proportion_n of_o a_o to_o b_o be_v great_a than_o the_o proportion_n of_o c_o to_o d_z let_v e_o be_v unto_o b_o as_z c_z be_v to_o d._n and_o so_o by_o the_o first_o part_n of_o the_o 10._o of_o this_o book_n e_o shall_v be_v less_o than_o a._n and_o therefore_o by_o the_o common_a sentence_n ebb_n shall_v be_v less_o than_o ab_fw-la wherefore_o by_o the_o first_o part_n of_o the_o 8._o of_o the_o same_o ab_fw-la have_v unto_o b_o a_o great_a proportion_n than_o have_v ebb_n to_o b._n but_o by_o composition_n ebb_n be_v to_o b_o as_o cd_o be_v to_o d._n for_o by_o supposition_n e_o be_v unto_o b_o as_o be_v to_o d._n wherefore_o by_o the_o 12._o of_o this_o book_n ab_fw-la have_v to_o b_o a_o great_a proportion_n than_o have_v cd_o to_o d_o which_o be_v require_v to_o be_v prove_v ¶_o the_o four_o proposition_n if_o there_o be_v four_o quantity_n and_o if_o the_o proportion_n of_o the_o first_o and_o the_o second_o to_o the_o second_o be_v great_a than_o the_o proportion_n of_o the_o three_o and_o four_o to_o the_o four_o then_o by_o division_n also_o the_o proportion_n of_o the_o first_o to_o the_o second_o shall_v be_v great_a th●n_n the_o proportion_n of_o the_o third_o to_o the_o four_o suppose_v that_o the_o proportion_n of_o ab_fw-la to_o b_o be_v great_a than_o the_o proportion_n of_o cd_o to_o d._n impossibility_n then_o i_o say_v that_o by_o division_n also_o the_o proportion_n of_o a_o to_o b_o be_v great_a than_o the_o proportion_n of_o c_o to_o d._n for_o it_o can_v be_v the_o same_o for_o then_o by_o composition_n ab_fw-la shall_v be_v to_o b_o as_o cd_o be_v to_o d._n neither_o also_o can_v it_o be_v less_o for_o if_o the_o proportion_n of_o c_o to_o d_z be_v great_a than_o the_o proportion_n of_o a_o to_o b_o then_o by_o the_o former_a proposition_n the_o proportion_n of_o cd_o to_o d_z shall_v be_v great_a than_o the_o proportion_n of_o ab_fw-la to_o b_o which_o be_v contrary_a also_o to_o the_o supposition_n wherefore_o the_o proportion_n of_o a_o to_o b_o be_v neither_o one_o and_o the_o same_o with_o the_o proportion_n of_o c_o to_o d_z 〈…〉_o it_o wherefore_o it_o be_v great_a than_o it_o which_o be_v require_v to_o be_v prove_v affirmative_o the_o same_o may_v also_o be_v prove_v affirmative_o suppose_v that_o ebb_n be_v unto_o b_o as_o cd_o be_v to_o d._n now_o then_o by_o the_o first_o part_n of_o the_o 10._o of_o the_o five_o ebb_n shall_v be_v less_o than_o ab_fw-la and_o therefore_o by_o the_o common_a sentence_n e_o be_v less_o than_o a_o wherefore_o by_o the_o first_o part_n of_o the_o 8._o of_o this_o book_n the_o proportion_n of_o e_o to_o b_o be_v less_o than_o the_o proportion_n of_o a_o to_o b_o but_o as_z e_o be_v to_o b_o so_o be_v c_z to_o d_z wherefore_o the_o proportion_n of_o c_o to_o d_z be_v less_o than_o the_o proportion_n of_o a_o to_o b._n wherefore_o the_o proportion_n of_o a_o to_o b_o be_v great_a than_o the_o proportion_n of_o c_o to_o d_z which_o be_v require_v to_o be_v prove_v ¶_o the_o five_o proposition_n if_o there_o be_v four_o quantity_n and_o if_o the_o proportion_n of_o the_o first_o and_o the_o second_o to_o the_o second_o be_v great_a than_o the_o proportion_n of_o the_o three_o and_o the_o four_o to_o the_o four_o then_o by_o eversion_n the_o proportion_n of_o the_o first_o and_o second_o to_o the_o first_o shall_v be_v less_o than_o the_o proportion_n of_o the_o three_o and_o four_o to_o the_o three_o suppose_v that_o the_o proportion_n of_o ab_fw-la to_o b_o be_v great_a than_o the_o proportion_n of_o cd_o to_o d._n then_o i_o say_v that_o by_o eversion_n the_o proportion_n of_o ab_fw-la to_o a_o be_v less_o than_o the_o proportion_n of_o cd_o to_o hundred_o demonstration_n for_o by_o division_n by_o the_o former_a proposition_n the_o proportion_n of_o a_o to_o b_o be_v great_a than_o the_o proportion_n of_o c_o to_o d._n wherefore_o by_o the_o first_o of_o these_o proposition_n converse_o b_o have_v unto_o a_o a_o less_o proportion_n they_o have_v d_z to_o c._n wherefore_o by_o the_o 3._o of_o the_o same_o by_o composition_n the_o proportion_n of_o ab_fw-la to_o a_o be_v less_o they_o the_o
the_o part_n add_v together_o be_v not_o equal_a to_o the_o whole_a nor_o make_v the_o whole_a but_o make_v either_o more_o or_o less_o wherefore_o of_o imperfect_a number_n there_o be_v two_o kind_n number_n the_o one_o be_v call_v abundant_a or_o a_o building_n the_o other_o 〈◊〉_d or_o want_v a_o number_n abund_v be_v that_o who_o part_n be_v all_o add_v together_o make_v more_o than_o the_o w●●ds_n number_n who_o part_n they_o be_v as_o 12._o be_v a_o abundant_a number_n for_o all_o the_o parte●_n of_o 12._o namely_o 6.4.3.2_o and_o 1._o add_v together_o make_v 16_o which_o be_v more_o than_o 12._o likewise_o 18._o be_v a_o number_n abund_v all_o his_o part●_n name_o 9.6.3.2_o and_o 1._o add_v together_o make_v 20._o which_o be_v more_o than_o 18_o and_o so_o of_o other_o wan●●ng●_n a_o number_n diminute_a or_o want_v be_v that_o who_o part_n be_v all_o add_v together_o make_v less_o than_o the_o whole_a or_o number_n who_o part_n they_o be_v as_o 9_o be_v a_o diminute_a or_o want_v number_n for_o all_o his_o part_n name_o 3._o and_o 1._o more_o part_n he_o have_v not_o add_v together_o make_v only_o 4_o which_o be_v less_o than_o 9_o also_o 26._o be_v a_o diminute_a number_n all_o his_o part_n namely_o 13.2.1_o add_v together_o make_v only_o 16_o which_o be_v a_o number_n much_o less_o than_o 26._o and_o so_o of_o such_o like_a sentence_n campane_n and_o flussates_n here_o add_v certain_a common_a sentence_n some_o of_o which_o for_o that_o they_o be_v in_o these_o three_o book_n follow_v sometime_o allege_v i_o think_v good_a here_o to_o annex_v sentence_n 1_o the_o less_o part_n be_v that_o which_o have_v the_o great_a denomination_n and_o the_o great_a part_n be_v that_o which_o have_v the_o less_o denomination_n as_o the_o number_n 6._o and_o 8._o be_v either_o of_o they_o a_o part_n of_o the_o number_n 24_o 6._o be_v a_o four_o part_n 4._o time_n 6._o be_v 24_o and_o 8._o be_v a_o three_o part_n 3._o time_n 8._o be_v 24._o now_o forasmuch_o as_o 4_o which_o denominate_v what_o part_n 6._o be_v of_o 24_o be_v great_a than_o 3._o which_o denominate_v what_o part_n 8._o be_v of_o 24._o therefore_o be_v 6._o a_o less_o part_n of_o 24●_n than_o be_v 8._o and_o so_o be_v 8._o a_o great_a part_n of_o 24._o they_o 6._o be_v and_o so_o in_o other_o sentence_n 2_o whatsoever_o number_n be_v equemultiplices_fw-la to_o one_o &_o the_o self_n same_o number_n or_o to_o equal_a number_n be_v also_o equal_a the_o one_o to_o the_o other_o as_o if_o unto_o the_o number_n 3_o be_v take_v two_o number_n contain_v the_o same_o number_n four_o time_n that_o be_v be_v equemultiplices_fw-la to_o the_o same_o number_n three_o the_o say_v two_o number_n shall_v be_v equal_a for_o 4._o time_n 3._o will_v ever_o be_v 12._o so_o also_o will_v it_o be_v if_o unto_o the_o two_o equal_a number_n 3._o &_o 3._o be_v take_v two_o number_n the_o one_o contain_v the_o one_o number_n 3._o four_o time_n the_o other_o contain_v the_o other_o number_n 3._o also_o four_o time_n that_o be_v be_v equemultiplices_fw-la to_o the_o equal_a number_n 3._o and_o 3._o sentence_n 3_o those_o number_n to_o who_o one_o and_o the_o self_n same_o number_n be_v equmultiplex_n or_o who_o equemultiplices_fw-la be_v equal_a be_v also_o equal_a the_o on_o to_o the_o other_o as_o if_o the_o number_n 18._o be_v equemultiplex_n to_o any_o two_o number_n that_o be_v contain_v any_o two_o number_n twice_o thrice_o four_o time_n &_o c_o as_o for_o example_n 3._o time_n then_o be_v the_o say_v two_o number_n equal_a for_o 18._o divide_v by_o 3._o will_v ever_o bring_v forth_o 6._o so_o that_o that_o division_n make_v twice_o will_v bring_v forth_o 6._o and_o 6._o two_o equal_a number_n so_o also_o will_v it_o follow_v if_o the_o two_o number_n have_v equal_a equemultiplices_fw-la namely_o if_o 18._o and_o 18._o which_o be_v equal_a number_n contain_v any_o two_o number_n 3._o time_n 4_o if_o a_o number_n measure_v the_o whole_a and_o a_o part_n take_v away_o it_o shall_v also_o measure_v the_o residue_n sentence_n as_o if_o from_o 24._o be_v take_v away_o 9_o there_o remain_v 15._o and_o for_o as_o much_o as_o the_o number_n 3_o measure_v the_o whole_a number_n 24_o &_o also_o the_o number_n take_v away_o namely_o 9_o it_o shall_v also_o measure_v the_o residue_n which_o be_v 15●_n for_o 3._o measure_v 15_o by_o five_o five_o time_n 3._o be_v 15._o and_o so_o of_o other_o sentence_n 5_o if_o a_o number_n measure_v any_o number_n it_o also_o measure_v every_o number_n that_o the_o say_a number_n measure_v as_o the_o number_n 6._o measure_v the_o number_n 12._o shall_v also_o measure_v all_o the_o number_n that_o 1●_o measureth●_n as_o the_o number_n 24.36.48.60_o and_o so_o forth_o which_o the_o number_n 12._o do_v measure_n by_o the_o number●_n 2.3.4_o and_o 5._o and_o for_o as_o much_o as_o the_o number_n 12._o do_v measure_v the_o number_n 24.36.48_o and_o 60._o and_o the_o number_n 6_o do_v measure_v the_o number_n 12._o namely_o by_o 2._o it_o follow_v by_o this_o common_a sentence_n that_o the_o number_n 6._o measure_v each_o of_o th●se_a number_n 24._o 36.48_o and_o 60._o and_o so_o of_o other_o 6_o if_o a_o number_n measure_v two_o number_n sentence_n it_o shall_v also_o measure_v the_o number_n compose_v of_o they_o as_o the_o number_n 3_o measure_v these_o two_o number_n 6._o and_o 9●_n it_o measure_v 6._o by_o 2d_o and_o 9_o by_o 3._o and_o therefore_o by_o this_o common_a sentence_n it_o measure_v the_o number_n 15._o which_o be_v compose_v of_o the_o number_n 6._o and_o 9_o namely_o it_o measure_v it_o by_o 5._o 7_o if_o in_o number_n there_o be_v proportion_n how_o manysoever_o equal_a or_o the_o self_n same_o to_o one_o proportion_n sentence_n they_o shall_v al●o_o be_v equal_a or_o the_o self_n same_o the_o one_o to_o the_o other_o as_o if_o the_o proportion_n of_o the_o number_n 6._o to_o the_o number_n 3._o be_v as_o the_o proportion_n of_o the_o number_n 8._o to_o the_o number_n 4_o if_o also_o the_o proportion_n of_o the_o number_n 10._o to_o the_o number_n 5._o be_v as_o the_o proportion_n of_o the_o number_n 8._o to_o the_o number_n 4_o then_o shall_v the_o proportion_n of_o the_o number_n 6._o to_o the_o number_n 3._o be_v as_o the_o proportion_n of_o the_o number_n 10._o be_v to_o the_o number_n 5_o namely_o each_o proportion_n be_v duple_n and_o so_o of_o other_o euclid_n in_o his_o ●_o book_n the_o 11._o proposition_n demonstrate_v this_o also_o in_o continual_a quantity_n which_o although_o as_o touch_v that_o kind_n of_o quantity_n it_o may_v have_v be_v put_v also_o as_o a_o principle_n as_o in_o number_n he_o take_v it_o yet_o for_o that_o in_o all_o magnitude_n their_o proportion_n can_v not_o be_v express_v as_o have_v before_o be_v note_v &_o shall_v be_v afterward_o in_o the_o ten_o book_n more_o at_o large_a make_v manifest_v therefore_o he_o demonstrate_v it_o there_o in_o that_o place_n and_o prove_v that_o it_o be_v true_a as_o touch_v all_o proportion_n general_o whither_o they_o be_v rational_a or_o irrational_a ¶_o the_o first_o proposition_n the_o first_o theorem_a if_o there_o be_v give_v two_o unequal_a number_n and_o if_o in_o take_v the_o less_o continual_o from_o the_o great_a the_o number_n remain_v do_v not_o measure_v the_o number_n go_v before_o until_o it_o shall_v come_v to_o unity_n then_o be_v those_o number_n which_o be_v at_o the_o beginning_n give_v prime_a the_o one_o to_o the_o other_o svppose_v that_o there_o be_v two_o unequal_a number_n ab_fw-la the_o great_a and_o cd_o the_o less_o and_o from_o ab_fw-la the_o great_a take_v away_o cd_o the_o less_o as_o o●ten_v as_o you_o can_v leave_v favorina_n constr●ctio●_n and_o from_o cd_o take_v away_o favorina_n as_o often_o as_o you_o can_v leave_v the_o number_n gc_o and_o from_o favorina_n take_v away_o gc_o as_o often_o as_o you_o can_v and_o so_o do_v continual_o till_o there_o remain_v only_a unity_n which_o let_v be_v ha._n absurdity_n then_o i_o say_v that_o no_o number_n measure_v the_o number_n ab_fw-la and_o cd_o for_o if_o it_o be_v possible_a let_v some_o number_n measure_v they_o and_o let_v the_o same_o be_v e._n now_o cd_o measure_n ab_fw-la leave_v a_o less_o number_n than_o itself_o which_o let_v be_v fa●_n ●_z and_o favorina_n measure_v dc_o leave_v also_o a_o less_o than_o itself_o namely_o gc_o and_o gc_o measure_v favorina_n leave_v unity_n ha._n and_o forasmuch_o as_o the_o number_n e_o measure_v dc_o and_o the_o number_n cd_o measure_v the_o number_n bf_o therefore_o the_o number_n e_o also_o measure_v bf_o and_o it_o measure_v the_o whole_a number_n basilius_n wherefore_o it_o also_o measure_v that_o which_o remain_v namely_o the_o number_n favorina_n by_o the_o
the_o double_a of_o b_o be_v prime_a unto_o the_o double_a of_o b_o then_o the_o two_o number_n whereof_o the_o number_n be_v compose_v namely_o the_o number_n compose_v of_o a_o and_o c_o and_o the_o double_a of_o b_o shall_v be_v prime_a the_o one_o to_o the_o other_o by_o the_o 30_o of_o the_o seven_o and_o therefore_o the_o number_n compose_v of_o a_o and_o c_o shall_v be_v prime_a to_o b_o take_v once_o for_o if_o any_o number_n shall_v measure_v the_o two_o number_n namely_o the_o number_n compose_v of_o a_o and_o c_o and_o the_o number_n b_o it_o shall_v also_o measure_v the_o number_n compose_v of_o a_o and_o c_o and_o the_o double_a of_o b_o by_o the_o 5._o common_a sentence_n of_o the_o seven_o which_o be_v not_o possible_a for_o that_o they_o be_v prove_v to_o be_v prime_a number_n here_o have_v i_o add_v a_o other_o demonstration_n of_o the_o former_a proposition_n after_o campane_n which_o prove_v that_o in_o number_n how_o many_o soever_o which_o be_v there_o prove_v only_o touch_v three_o number_n and_o the_o demonstration_n seement_n somewhat_o more_o perspicuous_a than_o theon_n demonstration_n and_o thus_o he_o put_v the_o proposition_n if_o number_n how_o many_o soever_o be_v in_o continual_a proportion_n be_v the_o least_o that_o have_v one_o &_o the_o same_o proportion_n with_o they_o every_o one_o of_o they_o shall_v be_v to_o the_o number_n compose_v of_o the_o rest_n prime_a second_o i_o say_v that_o this_o be_v so_o in_o every_o one_o of_o they_o namely_o that_o c_z be_v a_o prime_a number_n to_o the_o number_n compose_v of_o a_o b_o d._n for_o if_o not_o then_o as_o before_o let_v e_o measure_v c_o and_o the_o number_n compose_v of_o a_o b_o d_o which_o e_o shall_v be_v a_o number_n not_o prime_a either_o to_o fletcher_n or_o to_o g_z by_o the_o former_a proposition_n add_v by_o campane_n wherefore_o let_v h_o measure_v they_o and_o forasmuch_o as_o h_o measure_v e_o it_o shall_v also_o measure_v the_o whole_a a_o b_o c_o d_o who_o e_o measure_v and_o forasmuch_o as_o h_o measure_v one_o of_o these_o number_n fletcher_n or_o g_o it_o shall_v measure_v one_o of_o the_o extreme_n a_o or_o d_o which_o be_v produce_v of_o fletcher_n or_o g_o by_o the_o second_o of_o the_o eight_o if_o they_o be_v multiply_v into_o the_o mean_n l_o or_o k._n and_o moreover_o the_o same_o h_o shall_v measure_v the_o meame_n bc_o by_o the_o 5._o common_a sentence_n of_o the_o seven_o when_o as_o by_o supposition_n it_o measure_v either_o fletcher_n or_o g._n which_o measure_n b_o c_o by_o the_o second_o of_o the_o eight_o but_o the_o same_o h_o measure_v the_o whole_a a_o b_o c_o d_o as_o we_o have_v prove_v for_o that_o it_o measure_v e._n wherefore_o it_o shall_v also_o measure_v the_o residue_n namely_o the_o number_n compose_v of_o the_o extreme_n a_o and_o d_z by_o the_o 4._o common_a sentence_n of_o the_o seven_o and_o it_o measure_v one_o of_o these_o a_o or_o d_z for_o it_o measure_v one_o of_o these_o fletcher_n or_o g_o which_o produce_v a_o and_o d_z wherefore_o the_o same_o h_o shall_v measure_v one_o of_o these_o a_o or_o d_o and_o also_o the_o other_o of_o they_o by_o the_o former_a common_a sentence_n which_o number_n a_o and_o d_o be_v by_o the_o 3._o of_o the_o eight_o prime_n the_o one_o to_o the_o other_o which_o be_v absurd_a this_o may_v also_o be_v prove_v in_o every_o one_o of_o these_o number_n a_o b_o c_o d._n wherefore_o no_o number_n shall_v measure_v one_o of_o these_o number_n a_o b_o c_o d_o and_o the_o number_n compose_v of_o the_o rest_n wherefore_o they_o be_v prime_a the_o one_o to_o the_o other_o if_o therefore_o number_n how_o many_o soever_o etc_o etc_o which_o be_v require_v to_o be_v prove_v here_o as_o i_o promise_v i_o have_v add_v campane_n demonstration_n of_o those_o proposition_n in_o number_n which_o eucl●de_n in_o the_o second_o book_n demonstrate_v in_o line_n and_o that_o in_o this_o place_n so_o much_o the_o rather_o for_o that_o theon_n as_o we_o see_v in_o the_o demonstration_n of_o the_o 15._o proposition_n seem_v to_o allege_v the_o 3._o &_o 4._o proposition_n of_o the_o second_o book_n which_o although_o they_o concern_v line_n only_o yet_o as_o we_o there_o declare_v and_o prove_v be_v they_o true_a also_o in_o number_n ¶_o the_o first_o proposition_n add_v by_o campane_n that_o number_n which_o be_v produce_v of_o the_o multiplication_n of_o one_o number_n into_o number_n how_o many_o soever_o be_v equal_a to_o that_o number_n which_o be_v produce_v of_o the_o multiplication_n of_o the_o same_o number_n into_o the_o number_n compose_v of_o they_o this_o prove_v that_o in_o number_n which_o the_o first_o of_o the_o second_o prove_v touch_v line_n suppo●●_n that_o the_o number_n a_o be_v multiply_v into_o the_o number_n b_o and_o into_o the_o number_n c_o demonstratiou_n and_o into_o the_o number_n d_o do_v produce_v the_o number_n e_o f_o and_o g._n then_o i_o say_v that_o the_o number_n produce_v of_o a_o multiply_a into_o the_o number_n compose_v of_o b_o c_o and_o d_z be_v equal_a to_o the_o number_n compose_v of_o e_o f_o and_o g._n for_o by_o the_o converse_n of_o the_o definition_n of_o a_o number_n multiply_v what_o part_n unity_n be_v of_o a_o the_o self_n same_o part_n be_v b_o of_o e_o and_o c_o of_o fletcher_n and_o also_o d_z of_o g._n wherefore_o by_o the_o 5._o of_o the_o seven_o what_o part_n unity_n be_v of_o a_o the_o self_n same_o part_n be_v the_o number_n compose_v of_o b_o c_o and_o d_o of_o the_o number_n compose_v of_o e_o f_o and_o g._n wherefore_o by_o the_o definition_n that_o which_o be_v produce_v of_o a_o into_o the_o number_n compose_v of_o b_o c_o d_o be_v equal_a to_o the_o number_n compose_v of_o e_o f_o g_o which_o be_v require_v to_o be_v prove_v the_o second_o proposition_n that_o number_n which_o be_v produce_v of_o the_o multiplication_n of_o number_n how_o many_o soever_o into_o one_o number_n be_v equal_a to_o that_o number_n which_o be_v produce_v of_o the_o multiplication_n of_o the_o number_n compose_v of_o they_o into_o the_o same_o number_n this_o be_v the_o converse_n of_o the_o former_a as_o if_o the_o ●●●bers_n ●_o and_o g_z and_o d_o multiply_v into_o the_o number_n a_o do_v produce_v the_o number_n e_o and_o f_o and_o g._n former_a then_o the_o number_n compose_v of_o b_o c_o d._n multiply_v into_o the_o number_n a_o shall_v produce_v the_o number_n compose_v of_o the_o number_n e_o f_o g._n which_o thing_n be_v easy_o prove_v by_o the_o 16._o of_o the_o seven_o and_o by_o the_o former_a proposition_n ¶_o the_o three_o proposition_n that_o number_n which_o be_v produce_v of_o the_o multiplication_n of_o number_n how_o many_o soever_o into_o other_o number_n how_o many_o soever_o be_v equal_a to_o that_o number_n which_o be_v produce_v of_o the_o multiplication_n of_o the_o number_n compose_v of_o those_o first_o number_n into_o the_o number_n compose_v of_o these_o latter_a number_n as_o if_o the_o number_n a_o b_o c_o do_v multiply_v the_o number_n d_o e_o f_o each_o one_o each_o other_o and_o if_o the_o number_n produce_v be_v add_v together_o then_o i_o say_v that_o the_o number_n compose_v of_o the_o number_n produce_v be_v equal_a to_o the_o number_n produce_v of_o the_o number_n compose_v of_o the_o number_n a_o b_o demonstration_n c_o into_o the_o number_n compose_v of_o the_o number_n d_o e_o f._n for_o by_o the_o former_a proposition_n that_o which_o be_v produce_v of_o the_o number_n compose_v of_o a_o b_o c_o into_o d_z be_v equal_a to_o that_o which_o be_v produce_v of_o every_o one_o of_o the_o say_a number_n into_o d_o and_o by_o the_o same_o reason_n that_o which_o be_v produce_v of_o the_o number_n compose_v of_o a_o b_o c_o into_o e_o be_v equal_a to_o that_o which_o be_v produce_v of_o every_o one_o of_o the_o say_a number_n into_o e_o and_o so_o likewise_o that_o which_o be_v produce_v of_o the_o number_n compose_v of_o a_o b_o c_o into_o fletcher_n be_v equal_a to_o that_o which_o be_v produce_v of_o every_o one_o of_o the_o say_a number_n into_o f._n but_o by_o the_o first_o of_o these_o proposition_n th●●_n which_o be_v produce_v of_o the_o number_n compose_v of_o these_o number_n a_o b_o c_o into_o every_o one_o of_o these_o number_n d_o e_o fletcher_n be_v equal_a to_o that_o which_o be_v produce_v of_o the_o number_n compose_v into_o the_o number_n compose_v wherefore_o that_o be_v manifest_v which_o be_v require_v to_o be_v prove_v ¶_o the_o four_o proposition_n if_o a_o number_n be_v deu●●●d_v into_o part_n how_o many_o soever_o that_o number_n which_o be_v produce_v of_o the_o whole_a into_o himself_o be_v equal_a to_o that_o number_n which_o be_v produce_v of_o
that_o the_o line_n of_o be_v make_v equal_a to_o the_o line_n ad_fw-la which_o be_v the_o diameter_n of_o the_o square_n abcd_o of_o which_o square_v the_o line_n ab_fw-la be_v a_o side_n it_o be_v certain_a that_o the_o ●ide_v of_o a_o square_n be_v incommensurable_a in_o length_n to_o the_o diameter_n of_o the_o same_o square_n if_o there_o be_v yet_o find_v any_o one_o superficies_n which_o measure_v the_o two_o square_n abcd_o and_o efgh_a as_o here_o do_v the_o triangle_n abdella_n or_o the_o triangle_n acd_v note_v in_o the_o square_n abcd_o or_o any_o of_o the_o four_o triangle_n note_v in_o the_o square_a efgh_o as_o appear_v somewhat_o more_o manifest_o in_o the_o second_o example_n in_o the_o declaration_n of_o the_o last_o definition_n go_v before_o the_o line_n of_o be_v also_o a_o rational_a line_n note_v that_o these_o line_n which_o here_o be_v call_v rational_a line_n be_v not_o rational_a line_n of_o purpose_n or_o by_o supposition_n as_o be_v the_o first_o rational_a line_n but_o be_v rational_a only_o by_o reason_n of_o relation_n and_o comparison_n which_o they_o have_v unto_o it_o because_o they_o be_v commensurable_a unto_o it_o either_o in_o length_n and_o power_n or_o in_o power_n only_o far_o here_o be_v to_o be_v note_v that_o these_o word_n length_n and_o power_n and_o power_n only_o be_v join_v only_o with_o these_o worde●_n commensurable_a or_o incommensurable_a and_o be_v never_o join_v with_o these_o word_n rational_a or_o irrational_a so_o that_o no_o line_n can_v be_v call_v rational_a in_o length_n or_o in_o power_n nor_o like_o wise_a can_v they_o be_v call_v irrational_a in_o length_n or_o in_o power_n wherein_o undoubted_o campanus_n be_v deceive_v book_n who_o use_v those_o word_n &_o speech_n indifferent_o cause_v &_o bring_v in_o great_a obscurity_n to_o the_o proposition_n and_o demonstration_n of_o this_o book_n which_o he_o shall_v easy_o see_v which_o mark_v with_o diligence_n the_o demonstration_n of_o campanus_n in_o this_o book_n 7_o line_n which_o be_v incommensurable_a to_o the_o rational_a line_n be_v call_v irrational_a definition_n by_o line_n incommensurable_a to_o the_o rational_a line_n suppose_v in_o this_o place_n he_o understand_v such_o as_o be_v incommensurable_a unto_o it_o both_o in_o length_n and_o in_o power_n for_o there_o be_v no_o line_n incommensurable_a in_o power_n only_o for_o it_o can_v be_v that_o any_o line_n shall_v so_o be_v incommensurable_a in_o power_n only_o that_o they_o be_v not_o also_o incommensurable_a in_o length_n what_o so_o ever_o line_n be_v incommensurable_a in_o power_n the_o same_o be_v also_o incommensurable_a in_o length_n neither_o can_v euclid_n here_o in_o this_o place_n mean_a line_n incommensurable_a in_o length_n only_o for_o in_o the_o definition_n before_o he_o call_v they_o rational_a line_n neither_o may_v they_o be_v place_v amongst_o irrational_a line_n wherefore_o it_o remain_v that_o in_o this_o diffintion_n he_o speak_v only_o of_o those_o line_n which_o be_v incommensurable_a to_o the_o rational_a line_n first_o give_v and_o suppose_v both_o in_o length_n and_o in_o power_n which_o by_o all_o mean_n be_v incommensurable_a to_o the_o rational_a line_n &_o therefore_o most_o apt_o be_v they_o call_v irrational_a line_n this_o definition_n be_v easy_a to_o be_v understand_v by_o that_o which_o have_v be_v say_v before_o yet_o for_o the_o more_o plainness_n see_v this_o example_n let_v the_o ●●rst_a rational_a line_n suppose_v be_v the_o line_n ab_fw-la who_o square_a or_o quadrate_n let_v be_v abcd._n and_o let_v there_o be_v give_v a_o other_o line_n of_o which_o l●t_v be_v to_o the_o rational_a line_n incommensurable_a in_o length_n and_o power_n so_o that_o let_v no_o one_o line_n measure_v the_o length_n of_o the_o two_o line_n ab_fw-la and_o of_o and_o let_v the_o square_n of_o the_o line_n of_o be_v efgh_a now_o if_o also_o there_o be_v no_o one_o superficies_n which_o measure_v the_o two_o square_n abcd_o and_o efgh_a as_o be_v suppose_v to_o be_v in_o this_o example_n they_o be_v the_o line_n of_o a_o irrational_a line_n which_o word_n irrational_a as_o before_o do_v this_o word_n rational_a mislike_v many_o learned_a in_o this_o knowledge_n of_o geometry_n flussates_n uncertain_a as_o he_o leave_v the_o word_n rational_a and_o in_o stead_n thereof_o use_v this_o word_n certain_a so_o here_o he_o leave_v the_o word_n irrational_a and_o use_v in_o place_n thereof_o this_o word_n uncertain_a and_o ever_o name_v these_o line_n uncertain_a line_n petrus_n montaureus_n also_o mislike_v the_o word_n irrational_a will_v rather_o have_v they_o to_o be_v call_v surd_a line_n yet_o because_o this_o word_n irrational_a have_v ever_o by_o custom_n and_o long_a use_n so_o general_o be_v receive_n he_o use_v continual_o the_o same_o in_o greek_a such_o line_n be_v call_v 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d alogoi_n which_o signify_v nameless_a unspeakable_a uncertain_a in_o determinate_a line_n and_o with_o out_o proportion_n not_o that_o these_o irrational_a line_n have_v no_o proportion_n at_o all_o either_o to_o the_o first_o rational_a line_n or_o between_o themselves_o but_o be_v so_o name_v for_o that_o their_o proportion_n to_o the_o rational_a line_n can_v be_v express_v in_o number_n that_o be_v undoubted_o very_o untrue_a which_o many_o write_v that_o their_o proportion_n be_v unknown_a both_o to_o we_o and_o to_o nature_n be_v it_o not_o think_v you_o a_o thing_n very_o absurd_a to_o say_v that_o there_o be_v any_o thing_n in_o nature_n and_o produce_v by_o nature_n to_o be_v hide_v from_o nature_n and_o not_o to_o be_v know_v of_o nature_n it_o can_v not_o be_v say_v that_o their_o proportion_n be_v utter_o hide_v and_o unknown_a to_o we_o much_o less_o unto_o nature_n although_o we_o can_v geve_v they_o their_o name_n and_o distinct_o express_v they_o by_o number_n otherwise_o shall_v euclid_n have_v take_v all_o this_o travel_n and_o wonderful_a diligence_n bestow_v in_o this_o booke●_n in_o vain_a and_o to_o no_o use●_n in_o which_o he_o do_v nothing_o ell●_n but_o teach_v the_o propriety_n and_o passion_n of_o these_o irrational_a lines●_n and_o show_v the_o proportion_n which_o they_o have_v the_o one_o to_o the_o other_o here_o be_v also_o to_o be_v note_v which_o thing_n also_o tartalea_n have_v before_o diligent_o noted●_n that_o campanus_n and_o many_o other_o writer_n of_o geometry●_n over_o much_o ●●●ed_a and_o be_v deceive_v in_o that_o they_o write_v and_o teach_v that_o all_o these_o line_n who_o square_n be_v not_o signify_v and_o may_v be_v express_v by_o a_o square_a number_n although_o they_o may_v by_o any_o other_o number_n as_o by_o 11._o 12._o 14._o and_o such_o other_o not_o square_a number_n be_v irrational_a line_n which_o be_v manifest_o repugnant_a to_o the_o ground_n and_o principle_n of_o euclid_n who_o will_v that_o all_o line_n which_o be_v commensurable_a to_o the_o rational_a line_n whether_o it_o be_v in_o length_n and_o power_n or_o in_o power_n only_o shall_v be_v rational_a undoubted_o this_o have_v be_v one_o of_o the_o chief_a and_o great_a cause_n of_o the_o wonderful_a confusion_n and_o darkness_n of_o this_o book_n book_n which_o so_o have_v toss_v and_o turmoil_v the_o wit_n of_o all_o both_o writer_n and_o reader_n master_n and_o scholar_n and_o so_o overwhelm_v they_o that_o they_o can_v not_o with_o out_o infinite_a travel_n and_o sweat_v attain_v to_o the_o truth_n and_o perfect_a understanding_n thereof_o definition_n 8_o the_o square_n which_o be_v describe_v of_o the_o rational_a right_a line_n suppose_v be_v rational_a until_o this_o definition_n have_v euclid_n set_v forth_o the_o nature_n and_o propriety_n of_o the_o first_o kind_n of_o magnitude_n namely_o of_o line_n how_o they_o be_v rational_a or_o irrational_a now_o he_o begin_v to_o ●hew_v how_o the_o second_o kind_n of_o magnitude_n namely_o superficies_n be_v one_o to_o the_o other_o rational_a or_o irrational_a this_o definition_n be_v very_a plain_n suppose_v the_o line_n ab_fw-la to_o be_v the_o rational_a line_n have_v his_o part_n and_o division_n certain_o know_v the_o square_a of_o which_o line_n let_v be_v the_o square_a abcd._n now_o because_o it_o be_v the_o square_a of_o the_o rational_a line_n ab_fw-la it_o be_v also_o call_v rational_a and_o as_o the_o line_n ab_fw-la be_v the_o first_o rational_a line_n unto_o which_o other_o line_n compare_v be_v count_v rational_a or_o irrational_a so_o be_v the_o quadrat_fw-la or_o square_v thereof_o the_o ●irst_n rational_a superficies_n unto_o which_o all_o other_o square_n or_o figure_n compare_v be_v count_v and_o name_v rational_a or_o irrational_a 9_o such_o which_o be_v commensurable_a unto_o it_o be_v rational_a definition_n in_o this_o definition_n where_o it_o be_v say_v such_o as_o be_v commensurable_a to_o the_o square_n of_o the_o rational_a line_n be_v not_o understand_v only_o other_o square_n or_o
now_o forasmuch_o as_o d_z measure_v ab_fw-la and_o bc_o it_o also_o measure_v the_o whole_a magnitude_n ac_fw-la and_o it_o measure_v ab_fw-la wherefore_o d_z measure_v these_o magnitude_n ca_n and_o ab_fw-la wherefore_o ca_n &_o ab_fw-la be_v commensurable_a and_o they_o be_v suppose_v to_o be_v incommensurable●_n which_o be_v impossible_a wherefore_o no_o magnitude_n measure_v ab_fw-la and_o bc._n wherefore_o the_o magnitude_n ab_fw-la and_o bc_o be_v incommensurable_a and_o in_o like_a sort_n may_v they_o be_v prove_v to_o be_v incommensurable_a if_o the_o magnitude_n ac_fw-la be_v suppose_v to_o be_v incommensurable_a unto_o bc._n if_o therefore_o there_o be_v two_o magnitude_n incommensurable_a compose_v the_o whole_a also_o shall_v be_v incommensurable_a unto_o either_o of_o the_o two_o part_n component_a and_o if_o the_o whole_a be_v incommensurable_a to_o one_o of_o the_o part_n component_n those_o first_o magnitude_n shall_v be_v incommensurable_a which_o be_v require_v to_o be_v prove_v ¶_o a_o corollary_n add_v by_o montaureus_n if_o a_o whole_a magnitude_n be_v incommensurable_a to_o one_o of_o the_o two_o magnitude_n which_o make_v the_o whole_a magnitude_n it_o shall_v also_o be_v incommensurable_a to_o the_o other_o of_o the_o two_o magnitude_n for_o if_o the_o whole_a magnitude_n ac_fw-la be_v incommensurable_a unto_o the_o magnitude_n bc_o then_o by_o the_o 2_o part_n of_o this_o 16._o theorem_o the_o magnitude_n ab_fw-la and_o bc_o shall_v be_v incommensurable_a wherefore_o by_o the_o first_o part_n of_o the_o same_o theorem_a the_o magnitude_n ac_fw-la shall_v be_v incommensurable_a to_o either_o of_o these_o magnitude_n ab_fw-la and_o bc._n this_o corollary_n 〈◊〉_d use_v in_o the_o demonstration_n of_o the_o ●3_o theorem_a &_o also_o of_o other_o proposition_n ¶_o a_o assumpt_n if_o upon_o a_o right_a line_n be_v apply_v a_o parallelogram_n want_v in_o figure_n by_o a_o square_n the_o parallelogram_n so_o apply_v be_v equal_a to_o that_o parallelogram_n which_o be_v contain_v under_o the_o segment_n of_o the_o right_a line_n which_o segment_n be_v make_v by_o reason_n of_o that_o application_n this_o assumpt_n i_o before_o add_v as_o a_o corollary_n out_o of_o flussates_n after_o the_o 28._o proposition_n of_o the_o six_o book_n ¶_o the_o 14._o theorem_a the_o 17._o proposition_n if_o there_o be_v two_o right_a line_n unequal_a and_o if_o upon_o the_o great_a be_v apply_v a_o parallelogram_n equal_a unto_o the_o four_o part_n of_o the_o square_n of_o the_o less_o line_n and_o want_v in_o figure_n by_o a_o square_a if_o also_o the_o parallelogram_n thus_o apply_v divide_v the_o line_n where_o upon_o it_o be_v apply_v into_o part_n commensurable_a in_o length_n then_o shall_v the_o great_a line_n be_v in_o power_n more_o than_o the_o less_o by_o the_o square_n of_o a_o line_n commensurable_a in_o length_n unto_o the_o great_a and_o if_o the_o great_a be_v in_o power_n more_o than_o the_o less_o by_o the_o square_n of_o a_o right_a line_n commensurable_a in_o length_n unto_o the_o great_a and_o if_o also_o upon_o the_o great_a be_v apply_v a_o parallelogram_n equal_a unto_o the_o four_o part_n of_o the_o square_n of_o the_o less_o line_n and_o want_v in_o figure_n by_o a_o square_n then_o shall_v it_o divide_v the_o great_a line_n into_o part_n commensurable_a but_o now_o suppose_v that_o the_o line_n bc_o be_v in_o power_n more_o than_o the_o line_n a_o by_o the_o square_n of_o a_o line_n commensurable_a in_o length_n unto_o the_o line_n bc._n first_o and_o upon_o the_o line_n bc_o let_v there_o be_v apply_v a_o rectangle_n parallelogram_n equal_a unto_o the_o four_o part_n of_o the_o square_n of_o the_o line_n a_o and_o want_v in_o figure_n by_o a_o square_a and_o let_v the_o say_a parallelogram_n be_v that_o which_o be_v contain_v under_o the_o line_n bd_o and_o dc_o then_o must_v we_o prove_v that_o the_o line_n bd_o be_v unto_o the_o line_n dc_o commensurable_a in_o length_n the_o same_o construction_n and_o supposition_n that_o be_v before_o remain_v we_o may_v in_o like_a sort_n prove_v that_o the_o line_n bc_o be_v in_o power_n more_o than_o the_o line_n a_o by_o the_o square_n of_o the_o line_n fd._n but_o by_o supposition_n the_o line_n bc_o be_v in_o power_n more_o they_o the_o line_n a_o by_o the_o square_n of_o a_o line_n commensurable_a unto_o it_o in_o length_n wherefore_o the_o line_n bc_o be_v unto_o the_o line_n fd_v commensurable_a in_o length_n wherefore_o the_o line_n compose_v of_o the_o two_o line_n bf_o and_o dc_o be_v commensurable_a in_o length_n unto_o the_o line_n fd_o by_o the_o second_o part_n of_o the_o 15._o of_o the_o ten_o wherefore_o by_o the_o 12._o of_o the_o ten_o or_o by_o the_o first_o part_n of_o the_o 15._o of_o the_o ten_o the_o line_n bc_o be_v commensurable_a in_o length_n to_o the_o line_n compose_v of_o bf_o and_o dc_o but_o the_o whole_a line_n conpose_v bf_o and_o dc_o be_v commensurable_a in_o length_n unto_o dc_o for_o bf_o as_o before_o have_v be_v prove_v be_v equal_a to_o dc_o wherefore_o the_o line_n bc_o be_v commensurable_a in_o length_n unto_o the_o line_n dc_o by_o the_o 12._o of_o the_o ten_o wh●●●fore_o also_o the_o line_n bd_o be_v commensurable_a in_o length_n unto_o the_o line_n dc_o by_o the_o second_o part_n of_o th●_z 15._o of_o the_o te●th_n if_o therefore_o there_o be_v two_o right_a line_n unequal_a and_o if_o upon_o the_o great_a be_v apply_v a_o parallelogram_n equal_a unto_o the_o four_o part_n of_o the_o square_n of_o the_o less_o and_o want_v in_o figure_n by_o a_o square_a if_o also_o the_o parallelogram_n thus_o apply_v divide_v the_o line_n whereupon_o it_o be_v apply_v into_o part_n commensurable_a in_o length_n then_o shall_v the_o great_a line_n be_v in_o power_n more_o than_o the_o less_o by_o the_o square_n of_o a_o line_n commensurable_a in_o length_n unto_o the_o great_a and_o if_o the_o great_a be_v in_o power_n more_o than_o the_o less_o by_o the_o square_n of_o a_o line_n commensurable_a in_o length_n unto_o the_o great_a and_o if_o also_o upon_o the_o great_a be_v apply_v a_o parallelogram_n equal_a unto_o the_o four_o part_n of_o the_o square_n make_v of_o the_o less_o and_o want_v in_o figure_n by_o a_o square_n then_o shall_v it_o divide_v the_o great_a line_n into_o part_n commensurable_a in_o length_n which_o be_v require_v to_o be_v prove_v campan●_n after_o this_o proposition_n reach_v how_o we_o may_v ready_o apply_v upon_o the_o line_n bc_o a_o parallelogram_n equal_a to_o the_o four_o part_n of_o the_o square_n of_o half_n of_o the_o line_n a_o and_o want_v in_o figure_n by_o a_o square_a after_o this_o manner_n divide_v the_o line_n bc_o into_o two_o line_n in_o such_o sort_n that_o half_a of_o the_o line_n a_o shall_v be_v the_o mean_a proportional_a between_o those_o two_o line_n which_o be_v possible_a when_o as_o the_o line_n bc_o be_v suppose_v to_o be_v great_a than_o the_o line_n a_o and_o may_v thus_o be_v do_v proposition_n 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the_o opposite_a side_n unto_o it_o the_o triangle_n hkl_n and_o the_o pyramid_n who_o base_a be_v the_o triangle_n aeg_n and_o top_n the_o point_n h_o be_v equal_a to_o the_o pyramid_n who_o base_a be_v the_o triangle_n hkl_n and_o top_n the_o point_n d._n part_n wherefore_o the_o foresay_a two_o prism_n be_v great_a than_o the_o foresay_a two_o pyramid_n who_o base_n be_v the_o triangle_n aeg_n hkl_n and_o top_n the_o point_n h_o and_o d._n wherefore_o the_o whole_a pyramid_n who_o base_a be_v the_o triangle_n abc_n proposition_n and_o top_n the_o point_n d_o be_v divide_v into_o two_o pyramid_n equal_a and_o like_v the_o one_o to_o the_o other_o and_o like_v also_o unto_o the_o whole_a pyramid_n have_v also_o triangle_n to_o their_o base_n and_o into_o two_o equal_a prism_n and_o the_o two_o prism_n be_v great_a than_o half_a of_o the_o whole_a pyramid_n which_o be_v require_v to_o be_v demonstrate_v if_o you_o will_v with_o diligence_n read_v these_o four_o book_n follow_v of_o euclid_n which_o concern_v body_n and_o clear_o see_v the_o demonstration_n in_o they_o contain_v it_o shall_v be_v requisite_a for_o you_o when_o you_o come_v to_o any_o proposition_n which_o concern_v a_o body_n or_o body_n whether_o they_o be_v regular_a or_o not_o first_o to_o describe_v of_o p●s●ed_a paper_n according_a as_o i_o teach_v you_o in_o the_o end_n of_o the_o definition_n of_o the_o eleven_o book_n such_o a_o body_n or_o body_n as_o be_v there_o require_v and_o have_v your_o body_n or_o body_n thus_o describe_v when_o you_o have_v note_v it_o with_o letter_n according_a to_o the_o figure_n set_v forth_o upon_o a_o plain_a in_o the_o proposition_n follow_v the_o construction_n require_v in_o the_o proposition_n as_o for_o example_n in_o this_o three_o proposition_n it_o be_v say_v that_o every_o pyramid_n have_v a_o triangle_n to_o ●is_n base_a may_v be_v divide_v into_o two_o pyramid_n etc_n etc_n here_o first_o describe_v a_o pyramid_n of_o past_v paper_n ha●ing_v his_o base_a triangle_v it_o skill_v not_o whether_o it_o be_v equilater_n or_o equiangle_v or_o not_o only_o in_o this_o proposition_n be_v require_v that_o the_o base_a be_v a_o triangle_n then_o for_o that_o the_o proposition_n suppose_v the_o base_a of_o the_o pyramid_n to_o be_v the_o triangle_n abc_n note_v the_o base_a of_o your_o pyramid_n which_o you_o have_v describe_v with_o the_o letter_n abc_n and_o the_o top_n of_o your_o pyramid_n with_o the_o letter_n d_o for_o so_o be_v require_v in_o the_o proposition_n and_o thus_o have_v you_o your_o body_n order_v ready_a to_o the_o construction_n now_o in_o the_o construction_n it_o be_v require_v that_o you_o divide_v the_o line_n ab_fw-la bc_o ca._n etc_o etc_o namely_o the_o six_o line_n which_o be_v the_o side_n of_o the_o four_o triangle_n contain_v the_o pyramid_n into_o two_o equal_a part_n in_o the_o poyntet_fw-la ●_o f_o g_o etc_n etc_n that_o be_v you_o must_v divide_v the_o line_n ab_fw-la of_o your_o pyramid_n into_o two_o equal_a part_n and_o note_v the_o point_n of_o the_o division_n with_o the_o letter_n e_o and_o so_o the_o line_n bc_o be_v divide_v into_o two_o equal_a part_n note_v the_o point_n of_o the_o division_n with_o the_o letter_n f._n and_o so_o the_o rest_n and_o this_o order_n follow_v you_o as_o touch_v the_o rest_n of_o the_o construction_n there_o put_v and_o when_o you_o have_v finish_v the_o construction_n compare_v your_o body_n thus_o describe_v with_o the_o demonstration_n and_o it_o will_v make_v it_o very_o plain_a and_o easy_a to_o be_v understand_v whereas_o without_o such_o a_o body_n describe_v of_o matter_n it_o be_v hard_o for_o young_a beginner_n unless_o they_o have_v a_o very_a deep_a imagination_n full_o to_o conceive_v the_o demonstration_n by_o the_o sig●e_n as_o it_o be_v describe_v in_o a_o plain_a here_o for_o the_o better_a declaration_n of_o that_o which_o i_o have_v say_v have_v i_o set_v a_o figure_n who_o form_n if_o you_o describe_v upon_o past_v paper_n note_v with_o the_o like_a letter_n and_o cut_v the_o line_n ●a_o dam_n dc_o and_o fold_v it_o according_o it_o will_v make_v a_o pyramid_n describe_v according_a to_o the_o construction_n require_v in_o the_o proposition_n and_o this_o order_n follow_v you_o as_o touch_v all_o other_o proposition_n which_o concern_v body_n ¶_o a_o other_o demonstration_n after_o campane_n of_o the_o 3._o proposition_n suppose_v that_o there_o be_v a_o pyramid_n abcd_o have_v to_o his_o base_a the_o triangle_n bcd_o and_o let_v his_o top_n be_v the_o solid_a angle_n a_o from_o which_o let_v there_o be_v draw_v three_o subtended_a line_n ab_fw-la ac_fw-la and_o ad_fw-la to_o the_o three_o angle_n of_o the_o base_a and_o divide_v all_o the_o side_n of_o the_o base_a into_o two_o equal_a part_n in_o the_o three_o point_n e_o f_o g_o divide_v also_o the_o three_o subtended_a line_n ab_fw-la ac_fw-la and_o ad_fw-la in_o two_o equal_a part_n in_o the_o three_o point_n h_o edward_n l._n and_o draw_v in_o the_o base_a these_o two_o line_n of_o and_o eglantine_n so_o shall_v the_o base_a of_o the_o pyramid_n be_v divide_v into_o three_o superficiece_n whereof_o two_o be_v the_o two_o triangle_n bef_n and_o egg_v which_o be_v like_o both_o the_o one_o to_o the_o other_o and_o also_o to_o the_o whole_a base_a by_o the_o 2_o part_n of_o the_o second_o of_o the_o six_o &_o by_o the_o definition_n of_o like_a super●iciec●s_n &_o they_o be_v equal_v the_o one_o to_o the_o other_o by_o the_o 8._o of_o the_o first_o the_o three_o superficies_n be_v a_o quadrangled_a parallelogram_n namely_o efgc_n which_o be_v double_a to_o the_o triangle_n egg_v by_o the_o 40._o and_o 41._o of_o the_o first_o now_o then_o again_o from_o the_o point_n h_o draw_v unto_o the_o point_n e_o and_o f_o these_o two_o subtendent_fw-la line_n he_o and_o hf_o draw_v also_o a_o subtended_a line_n from_o the_o point_n king_n to_o the_o point_n g._n and_o draw_v these_o line_n hk_o kl_o and_o lh_o wherefore_o the_o whole_a pyramid_n abcd_o be_v divide_v into_o two_o pyramid_n which_o be_v hbef_n and_o ahkl_n and_o into_o two_o prism_n of_o which_o the_o one_o be_v ehfgkc_n and_o be_v set_v upon_o the_o quadrangled_a base_a cfge_n the_o other_o be_v egdhkl_n and_o have_v to_o his_o base_a the_o triangle_n egg_v now_o as_o touch_v the_o two_o pyramid_n hbef_a and_o ahkl_n that_o they_o be_v equal_v the_o one_o to_o the_o other_o and_o also_o that_o they_o be_v like_o both_o the_o one_o to_o the_o other_o and_o also_o to_o the_o whole_a it_o be_v manifest_a by_o the_o definition_n of_o equal_a and_o like_a body_n and_o by_o the_o 10._o of_o the_o eleven_o and_o by_o 2._o part_n of_o the_o second_o of_o the_o six_o and_o that_o the_o two_o prism_n be_v equal_a it_o
be_v manifest_a by_o the_o last_o of_o the_o eleven_o and_o now_o that_o both_o the_o prism_n take_v together_o be_v great_a than_o the_o half_a of_o the_o whole_a pyramid_n hereby_o it_o be_v manifest_a for_o that_o either_o of_o they_o may_v be_v divide_v into_o two_o pyramid_n of_o which_o the_o one_o be_v a_o triangular_a pyramid_n equal_a to_o one_o of_o the_o two_o pyramid_n into_o which_o together_o with_o the_o two_o prism_n be_v divide_v the_o whole_a pyramid_n and_o the_o other_o be_v a_o quadrangled_a pyramid_n double_a to_o the_o other_o pyramid_n wherefore_o it_o be_v plain_a that_o the_o two_o prism_n take_v together_o be_v three_o quarter_n of_o the_o whole_a pyramid_n divide_v but_o if_o you_o be_v desirous_a to_o know_v the_o proportion_n between_o they_o read_v the_o ●_o of_o this_o book_n but_o now_o here_o to_o this_o purpose_n it_o shall_v be_v sufficient_a to_o know_v that_o the_o two_o prism_n take_v together_o do_v exceed_v in_o quantity_n the_o two_o partial_a pyramid_n take_v together_o into_o which_o together_o with_o the_o two_o prism_n the_o whole_a pyramid_n be_v divide_v ¶_o the_o 4._o theorem_a the_o 4._o proposition_n if_o there_o be_v two_o pyramid_n under_o equal_a altitude_n have_v triangle_n to_o their_o base_n and_o either_o of_o those_o pyramid_n be_v divide_v into_o two_o pyramid_n equal_v the_o one_o to_o the_o other_o and_o like_v unto_o the_o whole_a and_o into_o two_o squall_n prism_n and_o again_o if_o in_o either_o of_o the_o pyramid_n make_v of_o the_o two_o first_o pyramid_n be_v still_o observe_v the_o same_o order_n and_o manner_n then_o as_o the_o base_a of_o the_o one_o pyramid_n be_v to_o the_o base_a of_o the_o other_o pyramid_n so_o be_v all_o the_o prism_n which_o be_v in_o the_o one_o pyramid_n to_o all_o the_o prism_n which_o be_v in_o the_o other_o be_v equal_a in_o multitude_n with_o they_o svppose_v that_o there_o be_v two_o pyramid_n under_o equal_a altitude_n have_v triangle_n to_o their_o base_n namely_o abc_n and_o def_n and_o have_v to_o their_o top_n the_o point_n g_o and_o h._n and_o let_v either_o of_o these_o pyramid_n be_v divide_v into_o two_o pyramid_n equal_v the_o one_o to_o the_o other_o and_o like_v unto_o the_o whole_a and_o into_o two_o equal_a prism_n according_a to_o the_o method_n of_o the_o former_a proposition_n and_o again_o let_v either_o of_o those_o pyramid_n so●_n make_v of_o the_o two_o first_o pyramid_n be_v imagine_v to_o be_v after_o the_o same_o order_n divide_v and_o so_o do_v continual_o then_o i_o say_v that_o as_o the_o base_a abc_n be_v to_o the_o base_a def_n so_o be_v all_o the_o prism_n which_o be_v in_o the_o pyramid_n abcg_o to_o all_o the_o prism_n which_o be_v in_o the_o pyramid_n defh_o be_v equal_a in_o multitude_n with_o they_o for_o forasmuch_o as_o the_o line_n bx_n be_v equal_a to_o the_o line_n xc_o and_o the_o line_n all_o to_o the_o line_n lc_n for_o as_o we_o see_v in_o the_o construction_n pertain_v to_o the_o former_a proposition_n all_o the_o six_o side_n of_o the_o whole_a pyramid_n be_v each_o divide_v into_o two_o equal_a part_n the_o like_a of_o which_o construction_n be_v in_o this_o proposition_n also_o suppose_v therefore_o the_o line_n xl_o be_v a_o parallel_n to_o the_o line_n ab_fw-la &_o the_o triangle_n abc_n be_v like_a to_o the_o triangle_n lxc_n by_o the_o corollary_n of_o the_o second_o of_o the_o six_o and_o by_o the_o same_o reason_n the_o triangle_n def_n be_v like_a to_o the_o triangle_n rwf_n and_o forasmuch_o as_o the_o line_n bc_o be_v double_a to_o the_o line_n cx_o and_o the_o line_n fe_o to_o the_o line_n fw_o therefore_o as_o the_o line_n bc_o be_v to_o the_o line_n cx_o so_o be_v the_o line_n of_o to_o the_o line_n fw_o and_o upon_o the_o line_n bc_o and_o cx_o be_v describe_v rectiline_a figure_n like_a and_o in_o like_a sort_n set_v namely_o the_o triangle_n abc_n and_o lxc_n and_o upon_o the_o line_n of_o and_o fw_o be_v also_o describe_v rectiline_a figure_n like_a and_o in_o like_a sort_n set_v namely_o the_o triangle_n def_n &_o rwf●_n but_o if_o there_o be_v four_o right_a line_n proportional_a the_o rectiline_a figure_n describe_v of_o they_o be_v like_a and_o in_o like_a sort_n set_v shall_v also_o be_v proportional_a by_o the_o 22._o of_o the_o six_o wherefore_o as_o the_o triangle_n abc_n be_v to_o the_o triangle_n lxc_n so_o be_v the_o triangle_n def_n to_o the_o triangle_n rwf_n wherefore_o alternate_o by_o the_o 16._o of_o the_o five_o as_o the_o triangle_n abc_n be_v to_o the_o triangle_n def_n so_o be_v the_o triangle_n lxc_n to_o the_o triangle_n rwf_n assumpt_n but_o as_o the_o triangle_n lxc_n be_v to_o the_o triangle_n rwf_n so_o be_v the_o prism_n who_o base_a be_v the_o triangle_n lxc_n and_o the_o opposite_a side_n unto_o it_o the_o triangle_n omnes_n to_o the_o prism_n who_o base_a be_v the_o triangle_n rwf_n and_o the_o opposite_a side_n unto_o it_o the_o triangle_n stv_n by_o the_o corollary_n of_o the_o 40._o of_o the_o eleven_o for_o these_o prism_n be_v under_o one_o &_o the_o self_n same_o altitude_n namely_o under_o the_o half_a of_o the_o altitude_n of_o the_o whole_a pyramid_n which_o pyramid_n be_v suppose_v to_o be_v under_o one_o and_o the_o self_n same_o altitude_n this_o be_v also_o prove_v in_o the_o assumpt_n follow_v wherefore_o by_o the_o 11._o of_o the_o five_o as_o the_o triangle_n abc_n be_v to_o the_o triangle_n def_n so_o be_v the_o prism_n who_o base_a be_v the_o triangle_n lxc_n and_o the_o opposite_a side_n unto_o it_o the_o triangle_n omnes_n to_o the_o prism_n who_o base_a be_v the_o triangle_n rwf_n and_o the_o opposite_a side_n unto_o it_o the_o triangle_n stv_n and_o forasmuch_o as_o there_o be_v two_o prism_n in_o the_o pyramid_n abcg_o equal_a the_o one_o to_o the_o other_o &_o two_o prism_n also_o in_o the_o pyramid_n defh_o equal_a the_o one_o to_o the_o other_o therefore_o as_o the_o prism_n who_o base_a be_v the_o parallelogram_n bklx_fw-fr and_o the_o opposite_a side_n unto_o it_o the_o line_n more_n be_v to_o the_o prism_n who_o base_a be_v the_o triangle_n lxc_n and_o the_o opposite_a side_n unto_o it_o the_o triangle_n omnes_n so_o be_v the_o prism_n who_o base_a be_v the_o parallelogram_n perw_n and_o the_o opposite_a unto_o it_o the_o line_n n-ab_n to_o the_o prism_n who_o base_a be_v the_o triangle_n rwf_n and_o the_o opposite_a side_n unto_o it_o the_o triangle_n stv_n wherefore_o by_o composition_n by_o the_o 18._o of_o the_o five_o as_o the_o prism_n kbxlmo_n &_o lxcmno_n be_v to_o the_o prism_n lxcmno_n so_o be_v the_o prism_n pewrst_a and_o rwfstv_n to_o the_o prism_n rwfstv_n wherefore_o alternate_o by_o the_o 16._o of_o the_o five_o as_o the_o two_o prism_n kbxlmo_n and_o lxcmno_n be_v to_o the_o two_o prism_n pewrst_a and_o rwfstv_n so_o be_v the_o prism_n lxcmno_n to_o the_o prism_n rwfstv_n but_o as_o the_o prism_n lxcmno_n be_v to_o the_o prism_n rwfstv_n so_o have_v we_o prove_v that_o the_o base_a lxc_n be_v to_o the_o base_a rwf_n and_o the_o base_a abc_n to_o the_o base_a def_n wherefore_o by_o the_o 16._o of_o the_o five_o as_o the_o triangle_n abc_n be_v to_o the_o triangle_n def_n so_o be_v both_o the_o prism_n which_o be_v in_o the_o pyramid_n abcg_o to_o both_o the_o prism_n which_o be_v in_o the_o pyramid_n defh_o and_o in_o like_a sort_n if_o we_o divide_v the_o other_o pyramid_n after_o the_o self_n same_o manner_n namely_o the_o pyramid_n omng_v and_o the_o pyramid_n stuh_o as_o the_o base_a omnes_n be_v to_o the_o base_a stv_n so_o shall_v both_o the_o prism_n that_o be_v in_o the_o pyramid_n omng_v be_v to_o both_o the_o prism_n which_o be_v in_o the_o pyramid_n stuh_o but_o as_o the_o base_a omnes_n be_v to_o the_o base_a stv_n so_o be_v the_o base_a abc_n to_o the_o base_a def_n wherefore_o by_o the_o 11._o of_o the_o five_o as_o the_o base_a abc_n be_v to_o the_o base_a def_n so_o be_v the_o two_o prism_n that_o be_v in_o the_o pyramid_n abcg_o to_o the_o two_o prism_n that_o be_v in_o the_o pyramid_n defh_o and_o the_o two_o prism_n that_o be_v in_o the_o pyramid_n omng_v to_o the_o two_o prism_n that_o be_v in_o the_o pyramid_n stuh_o and_o the_o four_o prism_n to_o the_o four_o prism_n and_o so_o also_o shall_v it_o follow_v in_o the_o prism_n make_v by_o divide_v the_o two_o pyramid_n aklo_n and_o dpr_n and_o of_o all_o the_o other_o pyramid_n in_o general_a be_v equal_a in_o multitude_n andrea_n that_o as_o the_o triangle_n lxc_n be_v to_o the_o triangle_n rwf_n so_o be_v the_o prism_n who_o base_a be_v the_o triangle_n lxc_n and_o the_o opposite_a side_n omnes_n assumpt_n to_o the_o prism_n who_o base_a be_v the_o triangle_n rwf_n and_o the_o
same_o be_v treble_a it_o be_v manifest_a by_o the_o 12._o of_o the_o five_o that_o all_o the_o prism_n be_v to_o all_o the_o pyramid_n treble_a wherefore_o parallelipipedon_n be_v treble_a to_o pyramid_n set_v upon_o the_o self_n same_o base_a with_o they_o and_o under_o the_o same_o altitude_n they_o for_o that_o they_o contain_v two_o prism_n three_o corollary_n if_o two_o prism_n be_v under_o one_o and_o the_o self_n same_o altitude_n have_v to_o their_o base_n either_o both_o triangle_n or_o both_o parallelogram_n the_o prism_n be_v the_o one_o to_o the_o other_o as_o their_o base_n be_v for_o forasmuch_o as_o those_o prism_n be_v equemultiqlice_n unto_o the_o pyramid_n upon_o the_o self_n same_o base_n and_o under_o the_o same_o altitude_n which_o pyramid_n be_v in_o proportion_n as_o their_o base_n it_o be_v manifest_a by_o the_o 15._o of_o the_o five_o that_o the_o prism_n be_v in_o the_o proportion_n of_o the_o base_n for_o by_o the_o former_a corollary_n the_o prism_n be_v treble_a to_o the_o pyramid_n s●t_v upon_o the_o triangular_a base_n four_o corollary_n prism_n be_v in_o sesquealtera_fw-la proportion_n to_o pyramid_n which_o have_v the_o self_n same_o quadrangled_a base_a that_o the_o prism_n have_v and_o be_v under_o the_o self_n same_o altitude_n for_o that_o pyramid_n contain_v two_o pyramid_n set_v upon_o a_o triangular_a base_a of_o the_o same_o prism_n for_o it_o be_v prove_v that_o that_o prism_n be_v treble_a to_o the_o pyramid_n which_o be_v set_v upon_o the_o half_a of_o his_o quadrangled_a base_a unto_o which_o the_o other_o which_o be_v set_v upon_o the_o whole_a base_a be_v double_a by_o the_o six_o of_o this_o book_n five_v corollary_n wherefore_o we_o may_v in_o like_a sort_n conclude_v that_o solid_n mention_v in_o the_o second_o corollary_n which_o solid_n campane_n call_v side_v column_n be_v under_o one_o and_o the_o self_n same_o altitude_n be_v in_o proportion_n the_o one_o to_o the_o other_o as_o their_o base_n which_o be_v poligonon_o figure_n for_o they_o be_v in_o the_o proportion_n of_o the_o pyramid_n or_o prism_n set_v upon_o the_o self_n same_o base_n and_o under_o the_o self_n same_o altitude_n that_o be_v they_o be_v in_o the_o proportion_n of_o the_o base_n of_o the_o say_a pyramid_n or_o prism_n for_o those_o solid_n may_v be_v divide_v into_o prism_n have_v the_o self_n same_o altitude_n when_o as_o their_o opposite_a base_n may_v be_v divide_v into_o triangle_n by_o the_o 20_o of_o the_o six_o upon_o which_o triangle_n prism_n be_v set_v be_v in_o proportion_n as_o their_o base_n by_o this_o 7._o proposition_n it_o plain_o appear_v that_o ●u●lide_a as_o it_o be_v before_o note_v in_o the_o diffinition●●_n under_o the_o definition_n of_o a_o prism_n comprehend_v also_o those_o kind_n of_o solid_n which_o campane_n call_v side_v column_n for_o in_o that_o he_o say_v every_o prism_n have_v a_o triangle_n to_o his_o base_a may_v be_v devided●_n etc_n etc_n he_o need_v not_o take_v a_o prism_n in_o that_o sense_n which_o campane_n and_o most_o man_n take_v it_o to_o have_v add_v that_o particle_n have_v to_o his_o base_a a_o triangle_n for_o by_o their_o sense_n there_o be_v no_o prism_n but_o it_o may_v have_v to_o his_o base_a a_o triangle●_n and_o so_o it_o may_v seem_v that_o euclid_n ought_v without_o exception_n have_v say_v that_o every_o prism_n whatsoever_o may_v be_v divide_v into_o three_o pyramid_n equal_a the_o one_o to_o the_o other_o have_v also_o triangle_n to_o ●heir_a base_n for_o so_o do_v campane_n and_o flussas_n put_v the_o proposition_n leave_v out_o the_o former_a particle_n have_v to_o his_o base_a a_o triangle_n which_o yet_o be_v red_a in_o the_o greek_a copy_n &_o not_o le●t_v out_o by_o any_o other_o interpreter_n know_v abroad_o except_o by_o campane_n and_o flussas_n yea_o and_o the_o corollary_n follow_v of_o this_o proposition_n add_v by_o theon_n or_o euclid_n and_o amend_v by_o m._n dee_n seem_v to_o confirm_v this_o sense_n of_o this_o ●s_a 〈◊〉_d make_v manifest_a that_o every_o pyramid_n be_v the_o three_o part_n of_o the_o prism_n have_v the_o same_o base_a with_o it_o and_o equal_a altitude_n for_o and_o if_o the_o base_a of_o the_o prism_n have_v any_o other_o right_o line_v figure_n than_o a_o triangle_n and_o also_o the_o superficies_n opposite_a to_o the_o base_a the_o same_o figure_n that_o prism_n may_v be_v divide_v into_o prism_n have_v triangle_v base_n and_o the_o superficiece_n to_o those_o base_n opposite_a also_o triangle_v a_o ●●ike_a and_o equal_o for_o there_o as_o we_o see_v be_v put_v these_o word_n ●or_a and_o if_o the_o base_a of_o the_o prism_n be_v any_o other_o right_o line_v figure●_n etc_n etc_n whereof_o a_o man_n may_v well_o infer_v that_o the_o base_a may_v be_v any_o other_o rectiline_a figure_n whatsoever_o &_o not_o only_o a_o triangle_n or_o a_o parallelogram_n and_o it_o be_v true_a also_o in_o that_o sense_n as_o it_o be_v plain_a to_o see_v by_o the_o second_o corollary_n add_v out_o of_o flussas_n which_o corollary_n as_o also_o the_o first_o of_o his_o corollary_n be_v in_o a_o manner_n all_o one_o with_o the_o corollary_n add_v by_o theon_n or_o euclid_n far_o theon_n in_o the_o demonstration_n of_o the_o 10._o proposition_n of_o this_o book_n as_o we_o shall_v afterwards_o see_v most_o plain_o call_v not_o only_o side_v column_n prism_n but_o also_o parallelipipedon_n and_o although_o the_o 40._o proposition_n of_o the_o eleven_o book_n may_v seem_v hereunto_o to_o be_v a_o l●t_n for_o that_o it_o can_v be_v understand_v of_o those_o prism_n only_o which_o have_v triangle_n to_o their_o like_a equal_a opposite_a and_o parallel_v side_n or_o but_o of_o some_o side_v column_n and_o not_o of_o all_o yet_o may_v that_o let_v be_v thus_o remove_v away_o to_o say_v that_o euclid_n in_o that_o proposition_n use_v genus_fw-la pro_fw-la specie_fw-la that_o be_v the_o general_a word_n for_o some_o special_a kind_n thereof_o which_o thing_n also_o be_v not_o rare_a not_o only_o with_o he_o but_o also_o with_o other_o learned_a philosopher_n thus_o much_o i_o think_v good_a by_o the_o way_n to_o note_v in_o far_a defence_n of_o euclid_n definition_n of_o a_o prism_n the_o 8._o theorem_a the_o 8._o proposition_n pyramid_n be_v like_o &_o have_a triangle_n to_o their_o base_n be_v in_o treble_a proportion_n the_o one_o to_o the_o other_o of_o that_o in_o which_o their_o side_n of_o like_a proportion_n be_v svppose_v that_o these_o pyramid_n who_o base_n be_v the_o triangle_n gbc_n and_o hef_n and_o top_n the_o point_n a_o and_o d_o be_v like_o and_o in_o like_a sort_n describe_v and_o let_v ab_fw-la and_o de_fw-fr be_v side_n of_o like_a proportion_n then_o i_o say_v that_o the_o pyramid_n abcg_o be_v to_o the_o pyramid_n defh_o in_o treble_a proportion_n of_o that_o in_o which_o the_o side_n ab_fw-la be_v to_o the_o side_n de._n make_v perfect_a the_o parallelipipedon_n namely_o the_o solid_n bckl_n &_o efxo_n and_o forasmuch_o as_o the_o pyramid_n abcg_o be_v like_a to_o the_o pyramid_n defh_o construction_n therefore_o the_o angle_n abc_n be_v equal_a to_o the_o angle_n def_n demonstration_n &_o the_o angle_n gbc_n to_o the_o angle_n hef_fw-fr and_o moreover_o the_o angle_n abg_o to_o the_o angle_n deh_fw-it and_o as_o the_o line_n ab_fw-la be_v to_o the_o line_n de_fw-fr so_o be_v the_o line_n bc_o to_o the_o line_n of_o and_o the_o line_n bg_o to_o the_o line_n eh_o and_o for_o that_o as_o the_o line_n ab_fw-la be_v to_o the_o line_n de_fw-fr so_o be_v the_o line_n bc_o to_o the_o line_n of_o and_o the_o side_n about_o the_o equal_a angle_n be_v proportional_a therefore_o the_o parallelogram_n bm_n be_v like_a to_o the_o parallelogram_n ep_n and_o by_o the_o same_o reason_n the_o parallelogram_n bn_o be_v like_a to_o the_o parallelogram_n er_fw-mi and_o the_o parellelogramme_n bk_o be_v like_a unto_o the_o parallelogram_n exit_fw-la wherefore_o the_o three_o parallelogram_n bm_n kb_o and_o bn_o be_v like_a to_o the_o three_o parallelogram_n ep_n exit_fw-la and_o er._n but_o the_o three_o parallelogram_n bm_n kb_o and_o bn_o be_v equal_a and_o like_a to_o the_o three_o opposite_a parallelogram_n and_o the_o three_o parallelogram_n ep_n exit_fw-la and_o ere_o be_v equal_a and_o like_a to_o the_o three_o opposite_a parallelogram_n wherefore_o the_o parallelipipedon_n bckl_n and_o efxo_n be_v comprehend_v under_o plain_a superficiece_n like_a and_o equal_a in_o multitude_n wherefore_o the_o solid_a bckl_n be_v like_a to_o the_o solid_a efxo_n but_o like_o parallelipipedon_n be_v by_o the_o 33._o of_o the_o eleven_o in_o treble_a proportion_n the_o one_o to_o the_o other_o of_o that_o in_o which_o side_n of_o like_a proportion_n be_v to_o side_n of_o like_a proportion_n wherefore_o the_o solid_a bckl_n be_v to_o the_o solid_a efxo_n in_o treble_a
line_n which_o subtend_v the_o angle_n zob_n to_o the_o three_o line_n which_o subtend_v the_o angle_n zkb_n but_o by_o construction_n boy_n be_v equal_a to_o bk_o therefore_o oz_n be_v equal_a to_o kz_o and_o the_o three_o al●o_o be_v equal_a to_o the_o three_o wherefore_o the_o point_n z_o in_o respect_n of_o the_o two_o triangle_n rectangle_v ozb_n and_o kzb_n determine_v one_o and_o the_o same_o magnitude_n i●_z the_o line_n bz_o which_o can_v not_o be_v if_o any_o other_o point_n in_o the_o line_n bz_o be_v assign_v near_o or_o far_o of_o from_o the_o point_n b._n one_o only_a point_n therefore_o be_v that_o at_o which_o the_o two_o perpendicular_n kz_o and_o oz_n fall_v but_o by_o construction_n oz_n fall_v at_o z_o the_o point_n and_o therefore_o at_o the_o same_o z_o do_v the_o perpendicular_a draw_v from_o king_n fall_v likewise_o which_o be_v require_v to_o be_v demonstrate_v although_o a_o brief_a monition_n may_v herein_o have_v serve_v for_o the_o pregnant_a or_o the_o humble_a learner_n yet_o for_o they_o that_o be_v well_o please_v to_o have_v thing_n make_v plain_a with_o many_o word_n and_o for_o the_o stiffnecked_a busy_a body_n it_o be_v necessary_a with_o my_o controlment_n of_o other_o to_o annex_v the_o cause_n &_o reason_n thereof_o both_o invincible_a and_o also_o evident_a a_o corollary_n 1._o hereby_o it_o be_v manifest_a that_o two_o equal_a circle_n cut_v one_o the_o other_o by_o the_o whole_a diameter_n if_o from_o one_o and_o the_o same_o end_n of_o their_o common_a diameter_n equal_a portion_n of_o their_o circumference_n be_v take_v and_o from_o the_o point_n end_v those_o equal_a portion_n two_o perpendicular_n be_v let_v down_o to_o their_o common_a diameter_n those_o perpendicular_n shall_v fall_v upon_o one_o and_o the_o same_o point_n of_o their_o common_a diameter_n 2._o second_o it_o follow_v that_o those_o perpendicular_n be_v equal_a ¶_o note_n from_o circle_n in_o our_o first_o supposition_n each_o to_o other_o perpendicular_o erect_v we_o proceed_v and_o infer_v now_o these_o corollary_n whether_o they_o be_v perpendicular_o erect_v or_o no_o by_o reasou_v the_o demonstration_n have_v a_o like_a force_n upon_o our_o supposition_n here_o use_v ¶_o the_o 16._o theorem_a the_o 18._o proposition_n sphere_n be_v in_o treble_a proportion_n the_o one_o to_o the_o other_o of_o that_o in_o which_o their_o diameter_n be_v svppose_v that_o there_o be_v two_o sphere_n abc_n and_o def_n and_o let_v their_o diameter_n be_v bc_o and_o ef._n then_o i_o say_v that_o the_o sphere_n abc_n be_v to_o the_o sphere_n def_n in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n bc_o be_v to_o the_o diameter_n ef._n proposition_n for_o if_o not_o than_o the_o sphere_n abc_n be_v in_o treble_a proportion_n of_o that_o in_o which_o bc_o be_v to_o of_o either_o to_o some_o sphere_n less_o than_o the_o sphere_n def_n or_o to_o some_o sphere_n great_a first_o let_v it_o be_v unto_o a_o less_o namely_o to_o ghk_v case_n and_o imagine_v that_o the_o sphere_n def_n and_o ghk_o be_v both_o about_o one_o and_o the_o self_n same_o centre_n impossibility_n and_o by_o the_o proposition_n next_o go_v before_o describe_v in_o the_o great_a sphere_n def_n a_o polihedron_n or_o a_o solid_a of_o many_o side_n not_o touch_v the_o superficies_n of_o the_o less_o sphere_n ghk_v and_o suppose_v also_o that_o in_o the_o sphere_n abc_n be_v inscribe_v a_o polihedron_n like_a to_o the_o polihedron_n which_o be_v in_o the_o sphere_n def_n wherefore_o by_o the_o corollary_n of_o the_o same_o the_o polihedron_n which_o be_v in_o the_o sphere_n abc_n be_v to_o the_o polihedron_n which_o be_v in_o the_o sphere_n def_n in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n bc_o be_v to_o the_o diameter_n ef._n but_o by_o supposition_n the_o sphere_n abc_n be_v to_o the_o sphere_n ghk_v in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n bc_o be_v to_o the_o diameter_n ef._n wherefore_o as_o the_o sphere_n abc_n be_v to_o the_o sphere_n ghk_o so_o be_v the_o polihedron_n which_o be_v describe_v in_o the_o sphere_n abc_n to_o the_o polihedron_n which_o be_v describe_v in_o the_o sphere_n def_n by_o the_o 11._o of_o the_o five_o wherefore_o alternate_o by_o the_o 16._o of_o the_o five_o as_o the_o sphere_n abc_n be_v to_o the_o polihedron_n which_o be_v describe_v in_o it_o so_o be_v the_o sphere_n ghk_v to_o the_o polihedron_n which_o be_v in_o the_o sphere_n def_n but_o the_o sphere_n abc_n be_v great_a than_o the_o polihedron_n which_o be_v describe_v in_o it_o wherefore_o also_o the_o sphere_n ghk_o be_v great_a than_o the_o polihedron_n which_o be_v in_o the_o sphere_n def_n by_o the_o 14._o of_o the_o five_o but_o it_o be_v also_o less_o for_o it_o be_v contain_v in_o it_o which_o impossible_a wherefore_o the_o sphere_n abc_n be_v not_o in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n bc_o be_v to_o the_o diameter_n of_o to_o any_o sphere_n less_o than_o the_o sphere_n def_n in_o like_a sort_n also_o may_v we_o prove_v that_o the_o sphere_n def_n be_v not_o in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n of_o be_v to_o the_o diameter_n bc_o to_o any_o sphere_n less_o than_o the_o sphere_n abc_n case_n now_o i_o say_v that_o the_o sphere_n abc_n be_v not_o in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n bc_o be_v to_o the_o diameter_n of_o to_o any_o sphere_n great_a they_o the_o sphere_n def_n for_o if_o it_o be_v possible_a let_v it_o be_v to_o a_o great_a namely_o to_o lmn_o wherefore_o by_o conversion_n the_o sphere_n lmn_o be_v to_o the_o sphere_n abc_n in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n of_o be_v to_o the_o diameter_n bc._n but_o as_o the_o sphere_n lmn_o be_v to_o the_o sphere_n abc_n so_o be_v the_o sphere_n def_n to_o some_o sphere_n less_o they_o the_o sphere_n abc_n boo●●_n as_o it_o have_v before_o be_v prove_v for_o the_o sphere_n lmn_o be_v great_a than_o the_o sphere_n def_n wherefore_o the_o sphere_n def_n be_v in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n of_o be_v to_o the_o diameter_n bc_o to_o some_o sphere_n less_o they_o the_o sphere_n abc_n which_o be_v prove_v to_o be_v impossible_a wherefore_o the_o sphere_n abc_n be_v not_o in_o treble_a proportion_n of_o that_o in_o which_o be_v be_v to_o of_o to_o any_o sphere_n great_a they_o the_o sphere_n def_n and_o it_o be_v also_o prove_v that_o it_o be_v not_o to_o any_o less_o wherefore_o the_o sphere_n abc_n be_v to_o the_o sphere_n def_n in_o treble_a proportion_n of_o that_o in_o which_o the_o diameter_n bc_o be_v to_o the_o diameter_n of_o which_o be_v require_v to_o be_v demonstrate_v a_o corollary_n add_v by_o flussas_n hereby_o it_o be_v manifest_a that_o sphere_n be_v the_o one_o to_o the_o other_o as_o like_o polihedrons_n and_o in_o like_a sort_n describe_v in_o they_o be_v namely_o each_o be_v in_o triple_a proportion_n of_o that_o in_o which_o the_o diameter_n a_o corollary_n add_v by_o m●_n dee_n it_o be_v then_o evident_a how_o to_o geve_v two_o right_a line_n have_v that_o proportion_n between_o they_o which_o any_o two_o sphere_n give_v have_v the_o one_o to_o the_o other_o for_o if_o to_o their_o diameter_n as_o to_o the_o first_o and_o second_o line_n of_o four_o in_o continual_a proportion_n you_o adjoin_v a_o three_o and_o a_o four_o line_n in_o continual_a proportion_n as_o i_o have_v teach_v before_o the_o first_o and_o four_o line_n shall_v answer_v the_o problem_n rule_n how_o general_a this_o rule_n be_v in_o any_o two_o like_a solid_n with_o their_o correspondent_a or_o omologall_n line_n i_o need_v not_o with_o more_o word_n declare_v ¶_o certain_a theorem_n and_o problem_n who_o use_n be_v manifold_a in_o sphere_n cones_n cylinder_n and_o other_o solid_n add_v by_o joh._n dee_n a_o theorem_a 1._o the_o whole_a superficies_n of_o any_o sphere_n be_v quadrupla_fw-la to_o the_o great_a circle_n in_o the_o same_o sphere_n contain_v it_o be_v needless_a to_o bring_v archimedes_n demonstration_n hereof_o into_o this_o place_n see_v his_o book_n of_o the_o sphere_n and_o cylinder_n with_o other_o his_o wo●kes_n be_v every_o where_o to_o be_v have_v and_o the_o demonstration_n thereof_o easy_a a_o theorem_a 2._o every_o sphere_n be_v quadrupl●_n to_o that_o cone_n who_o base_a be_v the_o great_a circle_n &_o height_n the_o semidiameter_n of_o the_o same_o sphere_n this_o be_v the_o 32._o proposition_n of_o archimedes_n fi●st_n book_n of_o the_o sphere_n and_o cylinder_n a_o problem_n 1._o a_o sphere_n be_v give_v to_o make_v a_o upright_a cone_n equal_a to_o the_o same_o or_o in_o any_o other_o proportion_n give_v between_o two_o right_a line_n and_o as_o concern_v the_o other_o part_n of_o
the_o square_a of_o ed_z to_o the_o square_n of_o dk_o but_o by_o construction_n ed_z be_v subquintuple_a to_o df._n wherefore_o the_o square_a of_o ed_z be_v subquintuple_a to_o the_o square_n of_o dk_o and_o therefore_o the_o square_a of_o dk_o be_v quintuple_a to_o the_o square_n of_o ed._n and_o ed_z be_v equal_a to_o ed_z by_o construction_n therefore_o the_o square_a of_o dk_o be_v quintuple_a to_o the_o square_n of_o e_o d._n wherefore_o the_o double_a of_o bd_o be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n who_o great_a segment_n be_v bk●_n ●_z by_o the_o second_o of_o this_o thirte●th_o but_o by_o construction_n ab_fw-la be_v the_o double_a of_o ●d●_n ●_z wherefore_o ab_fw-la be_v divide_v by_o extreme_a and_o mean_a proportion_n and_o his_o great_a segment_n be_v bk_o and_o thereby_o k●_n ●_z the_o point_n of_o the_o division_n we_o have_v therefore_o divide_v by_o extreme_a and_o mean_a proportion_n any_o right_a line_n give_v in_o length_n and_o position_n which_o be_v to_o be_v do_v note●_n each_o of_o these_o way_n may_v well_o be_v execute_v but_o in_o the_o first_o you_o have_v this_o advantage_n that_o the_o diameter_n be_v take_v at_o pleasure_n which_o ●n_v the_o second_o way_n be_v ever_o just_a thrice_o so_o long_o as_o the_o line_n give_v to_o be_v divide_v john_n dee_n ¶_o the_o 4._o theorem_a the_o 4._o proposition_n if_o a_o right_a line_n be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n the_o square_n make_v of_o the_o whole_a line_n and_o of_o the_o less_o segment_n be_v treble_a to_o the_o square_n make_v of_o the_o great_a segment_n svppose_v that_o the_o right_a line_n ab_fw-la be_v divide_v by_o a_o extreme_a &_o mean_a proportion_n in_o the_o point_n c._n and_o let_v the_o great_a segment_n thereof_o be_v ac_fw-la then_o i_o say_v that_o the_o square_n make_v of_o the_o line_n ab_fw-la and_o bc_o be_v treble_a to_o the_o square_n of_o the_o line_n ac_fw-la describe_v by_o the_o 46._o of_o the_o first_o upon_o the_o line_n ab_fw-la a_o square_a adeb_n and_o make_v perfect_a the_o figure_n now_o forasmuch_o as_o the_o line_n ab_fw-la demonstration_n be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n in_o the_o point_n c_o and_o the_o great_a segment_n thereof_o be_v the_o line_n ac_fw-la therefore_o that_o which_o be_v contain_v under_o the_o line_n ab_fw-la and_o bc_o be_v equal_a to_o the_o square_n of_o the_o line_n ac_fw-la but_o that_o which_o be_v contain_v under_o the_o line_n ab_fw-la and_o cb_o be_v the_o parallelogram_n ak_o and_o the_o square_a of_o the_o line_n ac_fw-la be_v the_o square_a fd._n wherefore_o the_o parallelogram_n ak_o be_v equal_a to_o the_o square_a fd._n and_o the_o parallelogram_n of_o be_v equal_a to_o the_o parallelogram_n fe_o put_v the_o square_a ck_n common_a to_o they_o both_o wherefore_o the_o whole_a parallelogram_n ak_o be_v equal_a to_o the_o whole_a parallelogram_n ce_fw-fr wherefore_o the_o parallelogram_n ce_fw-fr and_o ak_o be_v double_a to_o the_o parallelogram_n ak_o b●t_v the_o parallelogram_n ak_o and_o ce_fw-fr be_v the_o gnomon_n lmn_o and_o the_o square_a ck_n wherefore_o the_o gnomon_n lmn_o and_o the_o square_a ck_n be_v double_a to_o the_o parallelogram_n ak_o but_o it_o be_v prove_v that_o the_o parallelogram_n ak_o be_v equal_a to_o the_o square_a df._n wherefore_o the_o gnomon_n lmn_o and_o the_o square_a ck_n be_v double_a to_o the_o square_a df._n wherefore_o the_o gnomon_n lmn_o and_o the_o square_n ck_a and_o df_o be_v treble_a to_o the_o square_a df._n but_o the_o gnomon_n lmn_o and_o the_o square_n ck_a and_o df_o be_v the_o whole_a square_a ae_n together_o with_o the_o square_a ck_n which_o be_v the_o square_n of_o the_o line_n ab_fw-la and_o bc._n and_o df_o be_v the_o square_a of_o the_o line_n ac_fw-la wherefore_o the_o square_n of_o the_o line_n ab_fw-la and_o bc_o be_v treble_a to_o the_o square_n of_o the_o line_n ac_fw-la if_o therefore_o a_o right_a line_n be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n the_o square_n make_v of_o the_o whole_a line_n and_o of_o the_o less_o segment_n be_v treble_a to_o the_o square_n make_v of_o the_o great_a segment_n which_o be_v require_v to_o be_v prove_v look_v for_o a_o other_o demonstration_n of_o this_o proposition_n after_o the_o five_o proposition_n of_o this_o book_n ¶_o the_o 5._o theorem_a the_o 5._o proposition_n if_o a_o right_a line_n be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n and_o unto_o it_o be_v add_v a_o right_a ●ine_o proportion_n equal_a to_o the_o great_a segment_n the_o whole_a right_a line_n be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n and_o the_o great_a segment_n thereof_o be_v the_o right_a line_n give_v at_o the_o beginning_n svppose_v that_o the_o right_a line_n ab_fw-la be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n in_o the_o point_n c_o and_o let_v the_o great_a segment_n thereof_o be_v ac_fw-la and_o unto_o the_o line_n ab_fw-la add_v the_o line_n ad_fw-la equal_a to_o the_o line_n ac_fw-la then_o i_o say_v that_o the_o line_n d●_n be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n in_o the_o point_n a_o and_o the_o great_a segment_n thereof_o be_v the_o right_a line_n p●t_n at_o the_o beginning_n namely_o ab_fw-la describe_v by_o the_o 46._o of_o the_o first_o upon_o on_o the_o line_n ab_fw-la a_o square_a ae_n and_o make_v perfect_a the_o figure_n and_o forasmuch_o as_o the_o line_n ab_fw-la be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n in_o the_o point_n c_o therefore_o that_o which_o be_v contain_v under_o the_o line_n ab_fw-la and_o bc_o be_v equal_a to_o the_o square_n of_o the_o line_n ac_fw-la but_o that_o which_o be_v contain_v under_o the_o line_n ab_fw-la and_o bc_o be_v the_o parallelogram_n ce●_n and_o the_o square_a of_o the_o ●●ne_n ac_fw-la be_v the_o square_a ch._n wherefore_o the_o parallelogram_n ce_fw-fr be_v equal_a to_o the_o square_a ch._n but_o unto_o the_o square_a change_z be_v equal_a the_o square_a dh_o by_o the_o first_o of_o the_o six_o and_o unto_o the_o parallelogram_n ce_fw-fr be_v equal_a the_o parallelogram_n he._n wherefore_o the_o parallelogram_n dh_o be_v equal_a to_o the_o parallelogram_n he._n add_v the_o parallelogram_n hb_o common_a to_o they_o both_o wherefore_o the_o whole_a parallelogram_n dk_o be_v equal_a to_o the_o whole_a square_a ae_n and_o the_o parallelogram_n dk_o be_v that_o which_o be_v contain_v under_o the_o line_n bd_o and_o dam_fw-ge for_o the_o line_n ad_fw-la be_v equal_a to_o the_o line_n dl_o &_o the_o square_a ae_n be_v the_o square_a of_o the_o line_n ab_fw-la wherefore_o that_o which_o be_v contain_v under_o the_o line_n ad_fw-la and_o db_o be_v equal_a to_o the_o square_n of_o the_o line_n ab_fw-la wherefore_o as_o the_o line_n db_o be_v to_o the_o line_n basilius_n so_o be_v the_o line_n basilius_n to_o the_o line_n ad_fw-la by_o the_o 17._o of_o the_o six_o but_o the_o line_n db_o be_v great_a than_o the_o line_n basilius_n wherefore_o the_o line_n basilius_n be_v great_a than_o the_o line_n ad._n wherefore_o the_o line_n bd_o be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n in_o the_o point_n a_o and_o his_o great_a segment_n be_v the_o line_n ab_fw-la if_o therefore_o a_o right_a line_n be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n and_o unto_o ●t_a be_v add_v a_o right_a line_n equal_a to_o the_o great_a segment_n the_o whole_a right_a line_n be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n and_o the_o great_a segment_n thereof_o be_v the_o right_a line_n give_v at_o the_o beginning_n which_o be_v require_v to_o be_v demonstrate_v this_o proposition_n be_v again_o afterward_o demonstrate_v a_o corollary_n add_v by_o campane_n hereby_o it_o be_v 〈…〉_o from_o the_o grea●●●_n 〈◊〉_d of_o a_o line_n divide_v by_o a_o extreme_a &_o mean_a proportion_n proposition_n be_v 〈◊〉_d away_o 〈◊〉_d segment_n the_o say_v great_a a_o segment_n shall_v be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n and_o the_o great_a segment_n thereof_o shall_v be_v the_o line_n take_v away_o as_o let_v the_o line_n ●●_o be_v divide_v by_o a_o extreme_a and_o mean●_z proportion_n in_o the_o point_n c._n and_o le●_z the_o 〈…〉_o line_n 〈…〉_o a._n d._n i_o say_v that_o ac_fw-la be_v also_o divide_v by_o a_o extreme_a and_o mean●_z proportion_n in_o the_o point_n d_o and_o that_o his_o great_a portion_n be_v dc_o for_o by_o the_o definitino_fw-it of_o a_o line_n so_o divide_v ab_fw-la be_v to_o ac_fw-la as_o ac_fw-la be_v to_o cb._n but_o as_o ac_fw-la be_v to_o cb_o so_o be_v ac_fw-la to_o dc_o by_o the_o 7._o of_o the_o 〈…〉_o be_v equal_a to_o cb_o wherefore_o by_o the_o 11._o of_o the_o five_o as_z ab_fw-la be_v to_o ac_fw-la so_o be_v ac_fw-la to_o cd_o
the_o whole_a line_n mg_o to_o the_o whole_a line_n ea_fw-la by_o the_o 18._o of_o the_o five_o wherefore_o as_o mg_o the_o side_n of_o the_o cube_fw-la be_v to_o ea_fw-la the_o semidiameter_n so_o be_v the_o line_n fghim_n to_o the_o octohedron_n abkdlc_n inscribe_v in_o one_o &_o the_o self_n same_o sphere_n if_o therefore_o a_o cube_fw-la and_o a_o octohedron_n be_v contain_v in_o one_o and_o the_o self_n same_o sphere_n they_o shall_v be_v in_o proportion_n the_o one_o to_o the_o other_o as_o the_o side_n of_o the_o cube_fw-la be_v to_o the_o semidiameter_n of_o the_o sphere_n which_o be_v require_v to_o be_v demonstrate_v a_o corollary_n distinct_o to_o notify_v the_o power_n of_o the_o side_n of_o the_o five_o solid_n by_o the_o power_n of_o the_o diameter_n of_o the_o sphere_n the_o side_n of_o the_o tetrahedron_n and_o of_o the_o cube_fw-la do_v cut_v the_o power_n of_o the_o diameter_n of_o the_o sphere_n into_o two_o square_n which_o be_v in_o proportion_n double_a the_o one_o to_o the_o other_o the_o octohedron_n cut_v the_o power_n of_o the_o diameter_n into_o two_o equal_a square_n the_o icosahedron_n into_o two_o square_n who_o proportion_n be_v duple_n to_o the_o proportion_n of_o a_o line_n divide_v by_o a_o extreme_a and_o mean_a proportion_n who_o less_o segment_n be_v the_o side_n of_o the_o icosahedron_n and_o the_o dodecahedron_n into_o two_o square_n who_o proportion_n be_v quadruple_a to_o the_o proportion_n of_o a_o line_n divide_v by_o a_o extreme_a and_o mean_a proportion_n who_o less_o segment_n be_v the_o side_n of_o the_o dodecahedron_n for_o ad_fw-la the_o diameter_n of_o the_o sphere_n contain_v in_o power_n ab_fw-la the_o side_n of_o the_o tetrahedron_n and_o bd_o the_o side_n of_o the_o cube_fw-la which_o bd_o be_v in_o power_n half_a of_o the_o side_n ab_fw-la the_o diameter_n also_o of_o the_o sphere_n contain_v in_o power_n ac_fw-la and_o cd_o two_o equal_a side_n of_o the_o octohedron_n but_o the_o diameter_n contain_v in_o power_n the_o whole_a line_n ae_n and_o the_o great_a segment_n thereof_o ed_z which_o be_v the_o side_n of_o the_o icosahedron_n by_o the_o 15._o of_o this_o book_n wherefore_o their_o power_n be_v in_o duple_n proportion_n of_o that_o in_o which_o the_o side_n be_v by_o the_o first_o corollary_n of_o the_o 20._o of_o the_o six_o have_v their_o proportion_n duple_n to_o the_o proportion_n of_o a_o extreme_a &_o mean_a proportion_n far_o the_o diameter_n contain_v in_o power_n the_o whole_a line_n of_o and_o his_o less_o segment_n fd_o which_o be_v the_o side_n of_o the_o dodecahedron_n by_o the_o same_o 15._o of_o this_o book_n wherefore_o the_o whole_a have_v to_o the_o less_o ●_o double_a proportion_n of_o that_o which_o the_o extreme_a have_v to_o the_o mean_a namely_o of_o the_o whole_a to_o the_o great_a segment_n by_o the_o 10._o definition_n of_o the_o five_o it_o follow_v that_o the_o proportion_n of_o the_o power_n be_v double_a to_o the_o double_a proportion_n of_o the_o side_n by_o the_o same_o first_o corollary_n of_o the_o 20._o of_o the_o six_o that_o be_v be_v quadruple_a to_o the_o proportion_n of_o the_o extreme_a and_o of_o the_o mean_a by_o the_o definition_n of_o the_o six_o a_o advertisement_n add_v by_o flussas_n by_o this_o mean_n therefore_o the_o diameter_n of_o a_o sphere_n be_v give_v there_o shall_v be_v give_v the_o side_n of_o every_o one_o of_o the_o body_n inscribe_v and_o forasmuch_o as_o three_o of_o those_o body_n have_v their_o side_n commensurable_a in_o power_n only_o and_o not_o in_o length_n unto_o the_o diameter_n give_v for_o their_o power_n be_v in_o the_o proportion_n of_o a_o square_a number_n to_o a_o number_n not_o square_a wherefore_o they_o have_v not_o the_o proportion_n of_o a_o square_a number_n to_o a_o square_a number_n by_o the_o corollary_n of_o the_o 25._o of_o the_o eight_o wherefore_o also_o their_o side_n be_v incommensurabe_n in_o length_n by_o the_o 9_o of_o the_o ten_o therefore_o it_o be_v sufficient_a to_o compare_v the_o power_n and_o not_o the_o length_n of_o those_o side_n the_o one_o to_o the_o other●_n which_o power_n be_v contain_v in_o the_o power_n of_o the_o diameter_n namely_o from_o the_o power_n of_o the_o diameter_n let_v there_o ble_v take_v away_o the_o power_n of_o the_o cube_fw-la and_o there_o shall_v remain_v the_o power_n of_o the_o tetrahedron_n and_o take_v away_o the_o power_n of_o the_o tetrahedron_n there_o remain_v the_o power_n of_o the_o cube_fw-la and_o take_v away_o from_o the_o power_n of_o the_o diameter_n half_o the_o power_n thereof_o there_o shall_v be_v leave_v the_o power_n of_o the_o side_n of_o the_o octohedron_n but_o forasmuch_o as_o the_o side_n of_o the_o dodecahedron_n and_o of_o the_o icosahedron_n be_v prove_v to_o be_v irrational_a for_o the_o side_n of_o the_o icosahedron_n be_v a_o less_o line_n by_o the_o 16._o of_o the_o thirteen_o and_o the_o side_n of_o the_o dedocahedron_n be_v a_o residual_a line_n by_o the_o 17._o of_o the_o same_o therefore_o those_o side_n be_v unto_o the_o diameter_n which_o be_v a_o rational_a line_n set_v incommensurable_a both_o in_o length_n and_o in_o power_n wherefore_o their_o comparison_n can_v not_o be_v define_v or_o describe_v by_o any_o proportion_n express_v by_o number_n by_o the_o 8._o of_o the_o ten_o neither_o can_v they_o be_v compare_v the_o one_o to_o the_o other_o for_o irrational_a line_n of_o diverse_a kind_n be_v incommensurable_a the_o one_o to_o the_o other_o for_o if_o they_o shall_v be_v commensurable_a they_o shall_v be_v of_o one_o and_o the_o self_n same_o kind_n by_o the_o 103._o and_o 105._o of_o the_o ten_o which_o be_v impossible_a wherefore_o we_o seek_v to_o compare_v they_o to_o the_o power_n of_o the_o diameter_n think_v they_o can_v not_o be_v more_o apt_o express_v then_o by_o such_o proportion_n which_o cut_v that_o rational_a power_n of_o the_o diameter_n according_a to_o their_o side_n namely_o divide_v the_o power_n of_o the_o diameter_n by_o line_n which_o have_v that_o proportion_n that_o the_o great_a segment_n have_v to_o the_o less_o to_o put_v the_o less_o segment_n to_o be_v the_o side_n of_o the_o icosahedron_n &_o devide_v the_o say_a power_n of_o the_o diameter_n by_o line_n have_v the_o proportion_n of_o the_o whole_a to_o the_o less_o segment_n to_o express_v the_o side_n of_o the_o dodecahedron_n by_o the_o less_o segment_n which_o thing_n may_v well_o be_v do_v between_o magnitude_n incommensurable_a the_o end_n of_o the_o fourteen_o book_n of_o euclides_n element_n after_o flussas_n ¶_o the_o fifteen_o book_n of_o euclides_n element_n this_o finetenth_n and_o last_o book_n of_o euclid_n or_o rather_o the_o second_o book_n of_o appollonius_n or_o hypsicles_n book_n teach_v the_o inscription_n and_o circumscription_n of_o the_o five_o regular_a body_n one_o within_o and_o about_o a_o other_o a_o thing_n undouted_o pleasant_a and_o delectable_a in_o mind_n to_o contemplate_v and_o also_o 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side_n gd_v the_o angle_n m_o n_o under_o the_o side_n ab_fw-la the_o angle_n t_o s_o under_o the_o side_n bg_o the_o angle_n p_o oh_o and_o under_o the_o side_n agnostus_n the_o angle_n r_o q_o so_o there_o rest_v 4._o angle_n who_o true_a place_n we_o will_v now_o appoint_v forasmuch_o as_o a_o cube_fw-la contain_v in_o one_o and_o the_o self_n same_o sphere_n with_o a_o dodecahedron_n be_v inscribe_v in_o the_o same_o dodecahedron_n as_o it_o be_v manifest_a by_o the_o 17._o of_o the_o thirteen_o and_o 8._o of_o this_o book_n it_o follow_v that_o a_o cube_fw-la and_o a_o dodecahedron_n circumscribe_v about_o it_o be_v contain_v in_o one_o and_o the_o self_n same_o body_n for_o that_o their_o angle_n concur_v in_o one_o and_o the_o self_n same_o point_n and_o it_o be_v prove_v in_o the_o 18._o of_o this_o book_n that_o 4._o angle_n of_o the_o cube_fw-la inscribe_v in_o the_o pyramid_n be_v set_v in_o the_o middle_a section_n of_o the_o perpendicular●_n which_o be_v draw_v from_o 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which_o thing_n flussas_n consider_v in_o this_o sixteen_o book_n add_v by_o he_o book_n have_v excellent_o well_o and_o most_o cunning_o perform_v for_o which_o undoubted_o he_o have_v of_o all_o they_o which_o have_v a_o love_n to_o the_o mathematicals_n deserve_v much_o praise_n and_o commendation_n both_o for_o the_o great_a tra●ailes_n and_o payn●s_n which_o it_o be_v most_o likely_a he_o have_v ta●●n_v in_o invent_v such_o strange_a and_o wonderful_a proposition_n with_o their_o demonstration_n in_o this_o book_n contain_v as_o also_o for_o participate_v and_o communicate_v abroad_o the_o same_o to_o other_o which_o book_n also_o that_o the_o reader_n shall_v want_v nothing_o conduce_v to_o the_o perfection_n of_o euclides_n element_n i_o have_v with_o some_o travail_n translate_v &_o for_o the_o worthiness_n ●hereof_o have_v add_v it_o a●_z a_o sixteen_o book_n to_o the_o 15._o book_n of_o euclid_n vouchsafe_v therefore_o gentle_a reader_n diligent_o to_o read_v and_o poise_v it_o for_o in_o it_o shall_v you_o find_v no●_n only_a matter_n strange_a and_o delectable_a but_o also_o occasion_n of_o invention_n of_o great_a thing_n pertain_v to_o the_o nature_n of_o the_o five_o regular_a solid●s●_n ¶_o the_o 1._o proposition_n a_o dodecahedron_n and_o a_o cube_fw-la inscribe_v in_o it_o and_o a_o pyramid_n inscribe_v in_o the_o same_o cube_fw-la be_v contain_v in_o one_o and_o the_o self_n same_o sphere_n for_o the_o angle_n of_o the_o pyrami●_n be_v se●_z in_o the_o angel_n of_o the_o cube_fw-la wherein_o it_o be_v inscribe_v by_o the_o first_o of_o the_o fivetenth●_n and_o all_o the_o angle_n of_o the_o cube_fw-la be_v set_v in_o the_o angle_n of_o the_o dodecahed●●●_n circumscribe_v 〈…〉_o 〈◊〉_d the_o 8._o of_o the_o fifteen_o and_o all_o the_o angle_n of_o the_o dodecahedron_n be_v set_v in_o the_o superficies_n of_o the_o sphere_n by_o the_o 17._o of_o the_o thirteen_o wherefore_o those_o three_o solid_n inscribe_v one_o within_o a_o other_o be_v contain_v 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a_o right_a line_n couple_v their_o centre_n be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n make_v the_o great_a segment_n the_o right_a line_n which_o couple_v the_o centre_n of_o the_o next_o base_n if_o by_o the_o centre_n of_o five_o base_n set_v upon_o one_o base_a be_v draw_v a_o plain_a superficies_n and_o by_o the_o centre_n of_o the_o base_n which_o be_v set_v upon_o the_o opposite_a base_a be_v draw_v also_o a_o plain_a superficies_n and_o then_o be_v draw_v a_o right_a line_n couple_v the_o centre_n of_o the_o opposite_a base_n that_o right_a line_n be_v so_o cut_v that_o each_o of_o his_o part_n set_v without_o the_o plain_a superficies_n be_v the_o great_a segment_n of_o that_o part_n which_o be_v contain_v between_o the_o plain_n the_o side_n of_o the_o dodecahedron_n be_v the_o great_a segment_n of_o the_o line_n which_o subtend_v the_o angle_n of_o the_o pentagon_n a_o perpendicular_a line_n draw_v from_o the_o centre_n of_o the_o dodecahedron_n to_o one_o 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the_o dodecahedron_n ¶_o the_o end_n of_o the_o element_n of_o geometry_n of_o the_o most_o ancient_a philosopher_n 〈◊〉_d of_o megara_n the_o intent_n of_o this_o preface_n number_n note_v the_o word_n unit_fw-la to_o express_v the_o greek_a mona●_n &_o not_o unity_n as_o we_o hau●_n all_o common_o till_o now_o use_v magnitude_n a_o point_n a_o line_n magnitude_n ano._n 1488._o ☞_o arithmetic_n note_n note_n anno._n 1550._o r._n b._n note_n 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d ☞_o this_o noble_a earl_n die_v anno._n 1554._o scarce_o of_o 24._o year_n of_o age●_n have_v no_o issue_n by_o his_o wife_n daughter_n to_o the_o duke_n of_o somerset_n justice._n ☞_o ☞_o plato_n 7._o de_fw-fr rep._n ☞_o ☞_o note_n the_o difference_n between_o strataruhmetrie_n and_o tacticie_n i.d._n f●end●●_n you_o will_v find_v it_o hard_o to_o perform_v my_o description_n of_o ●his_n f●ate_n but_o by_o ch●r●graphie●_n you_o may_v help_v yourself_o some_o ●hat_n wher●_n th●_z figure_v know_v in_o sid●●●nd_a angle_n 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●orth_o and_o therefore_o in_o s●me_a examplar_n it_o be_v not_o find_v construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n a_o corollary_n i_o dee_n dee_n the_o second_o corollary_n corollary_n therefore_o if_o you_o divide_v the_o square_n of_o the_o side_n ac_fw-la by_o the_o side_n bc_o the_o portion_n dc_o will_v be_v the_o product_n etc_n etc_n as_o in_o the_o former_a corollary_n i_o d●e_n d●e_n the_o third_o corollary_n corollary_n therefore_o if_o the_o parallelogram_n of_o basilius_n and_o ac_fw-la be_v divide_v by_o bc_o the_o product_n will_v geve_v the_o perpendicular_a d_o a._n these_o three_o corollarye_n in_o practice_n logistical_a and_o geometrical_a be_v profitable_a an_o other_o demonstration_n of_o this_o four_o part_n of_o the_o determination_n a_o assumpt_n construction_n demonstration_n the_o first_o part_n of_o the_o determination_n conclude_v the_o second_o part_n conclude_v the_o total_a conclusion_n construction_n 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cas●_n demonstration_n construction_n demonstration_n demonstration_n lead_v to_o a_o impossibility_n note_v this_o manner_n of_o imagination_n mathematical_a demonstration_n lead_v to_o a_o impossibility_n construction_n demonstration_n demonstration_n lead_v to_o a_o absurdity_n in_o t●is_fw-la ●rono●●●o●●●_n must_v understand_v the_o proportional_a ●artes_n or_o s●●●ions_n to_o be_v th●se_a which_o be_v contain_v 〈◊〉_d the_o parallel_a superficies_n construction_n demonstration_n construction_n demonstration_n demonstration_n lead_v to_o a_o impossibility_n demonstration_n construction_n demonstration_n two_o case_n in_o this_o proposition_n the_o first_o case_n second_o case_n construction_n demonstration_n an_o other_o demonstration_n construction_n demonstration_n construction_n three_o case_n in_o this_o proposition_n the_o first_o case_n a_o necessary_a thing_n to_o be_v prove_v before_o he_o procee_v any_o ●arther_a in_o the_o construction_n of_o the_o problem_n problem_n 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demonstration_n demonstration_n the_o circle_n so_o make_v or_o so_o consider_v in_o the_o sphere_n be_v call_v the_o great_a circle_n all_o other_o not_o have_v the_o centre_n of_o the_o sphere_n to_o be_v their_o centre_n also●_n be_v call_v less_o circle_n note_v these_o description_n description_n an_o other_o corollary_n corollary_n an_o other_o corollary_n construction_n construction_n this_o be_v also_o prove_v in_o the_o assumpt_n before_o add_v out_o o●_n flussas_n note_v what_o a_o great_a or_o great_a circle_n in_o a_o spear_n be_v first_o part_n of_o the_o construction_n note●_n note●_n you_o know_v full_a well_o that_o in_o the_o superficies_n of_o the_o sphere_n ●●●ly_o the_o circumference_n of_o the_o circle_n be_v but_o by_o th●se_a circumference_n the_o limitation_n and_o assign_v of_o circle_n be_v use_v and_o so_o the_o circumference_n of_o a_o circle_n usual_o call_v a_o circle_n which_o in_o this_o place_n can_v not_o offend_v this_o figure_n be_v restore_v by_o m._n dee_n his_o diligence_n for_o in_o the_o greek_a and_o latin_a euclides_n the_o line_n gl_n the_o line_n agnostus_n and_o the_o line_n kz_o in_o which_o three_o line_n the_o chief_a pinch_n of_o both_o the_o demonstration_n do_v stand_v be_v untrue_o draw_v as_o by_o compare_v the_o studious_a may_v perceive_v note_n you_o must_v imagine_v 〈◊〉_d right_a line_n axe_n to_o be_v perpendicular_a upon_o the_o diameter_n bd_o and_o ce_fw-fr though_o here_o ac_fw-la the_o semidiater_n seem_v to_o be_v part_n of_o ax._n and_o so_o in_o other_o point_n in_o this_o figure_n and_o many_o other_o strengthen_v your_o imagination_n according_a to_o the_o tenor_n of_o construction_n though_o in_o the_o delineation_n in_o plain_a sense_n be_v not_o satisfy_v note_n boy_n equal_a to_o bk_o in_o respect_n of_o m._n dee_n his_o demonstration_n follow_v follow_v note_v ●his_fw-la point_n z_o that_o you_o may_v the_o better_a understand_v m._n dee_n his_o demonstration_n second_o part_n of_o the_o 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construction_n demonstration_n construction_n demonstration_n this_o in_o manner_n of_o a_o lemm●_n be_v present_o prove_v note_v here_o of_o axe_n base_a &_o solidity_n more_o than_o i_o need_n to_o bring_v any_o far_a proof_n for_o note_n note_n i_o say_v half_a a_o circular_a revolution_n for_o that_o suffice_v in_o the_o whole_a diameter_n n-ab_n to_o describe_v a_o circle_n by_o i●_z it_o be_v move_v ●●out_v his_o centre_n q_o etc_n etc_n lib_fw-la 2_o prop_n 2._o de_fw-fr sphe●a_n &_o cylindr●_n note_n note_n a_o rectangle_n parallelipipedon_n give_v equal_a to_o a_o sphere_n give_v to_o a_o sphere_n or_o to_o any_o part_n of_o a_o sphere_n assign_v as_o a_o three_o four_o five_o etc_o etc_o to_o geve_v a_o parallelipipedon_n equal_a side_v colume_n pyramid_n and_o prism_n to_o be_v give_v equal_a to_o a_o sphere_n or_o to_o any_o certain_a part_n thereof_o to_o a_o sphere_n or_o any_o segment_n or_o sector_n of_o the_o same_o to_o geve_v a_o cone_n or_o cylinder_n equal_a or_o 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add_v upon_o the_o second_o proposition_n dc_o be_v divide_v by_o extreme_a and_o mean_a proportion_n in_o the_o point_n a._n and_o because_o ac_fw-la be_v big_a than_o cb_o therefore_o dam_n be_v great_a than_o ac_fw-la wherefore_o if_o a_o right_a line_n etc_n etc_n as_o in_o the_o proposition_n which_o be_v to_o be_v demonstrate_v demonstrate_v therefore_o by_o my_o second_o theorem_a add_v upon_o the_o second_o proposition_n dc_o be_v divide_v by_o extreme_a and_o mean_a proportion_n in_o the_o point_n a._n and_o because_o ac_fw-la be_v big_a than_o cb_o therefore_o dam_n be_v great_a than_o ac_fw-la wherefore_o if_o a_o right_a line_n etc_n etc_n as_o in_o the_o proposition_n which_o be_v to_o be_v demonstrate_v construction_n construction_n though_o i_o say_v perpendicular_a yes_o you_o may_v perceive_v how_o infinite_a other_o position_n will_v serve_v so_o that_o diego_n and_o ad_fw-la make_v a_o angle_n for_o a_o triangle_n to_o have_v his_o side_n proportional_o cut_v etc_n 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demonstration_n two_o case_n in_o this_o proposition_n construction_n th●_z first_o case_n demonstration_n the_o second_o case_n construction_n demonstration_n construction_n demonstration_n this_o corollary_n be_v the_o 3._o proposition_n of_o the●4_n ●4_o book_n after_o campane_n demonstration_n of_o the_o first_o part_n demonstration_n of_o the_o second_o part_n construction_n demonstration_n construstion_n demonstration_n constr●yction_n demonstration_n this_o corollary_n be_v the_o 11._o proposition_n of_o the_o 14._o book_n after_o campane_n this_o corollary_n be_v the_o 3._o corollary_n after_o the_o 17._o proposition_n of_o the_o 14_o book_n after_o campane_n campane_n by_o the_o name_n o●_n a_o pyramid_n both_o here_o &_o i●_z this_o book_n follow_v understand_v a_o tetrahedron_n an_o other_o construction_n and_o demonstration_n of_o the_o second_o part_n after_o f●ussas_n three_o part_n of_o the_o demonstration_n this_o corollary_n be_v the_o 15._o proposition_n of_o the_o 14._o book_n after_o campane_n this_o corollary_n campane_n put_v as_o a_o corollary_n after_o
the_o 17._o proposition_n of_o the_o 14._o book_n construction_n ●rist_n part_n of_o the_o demonstration_n demonstration_n for_o the_o 4._o angle_n at_o the_o point_n king_n be_v equal_a to_o four_o right_a angle_n by_o the_o corollary_n of_o t●e_z 15._o of_o the_o first_o and_o those_o 4._o angle_n be_v equal_a the_o one_o to_o the_o other_o by_o the_o ●_o of_o the_o ●irst_n and_o therefore_o each_o be_v a_o right_a angle_n second_o part_n of_o the_o demonstration_n demonstration_n for_o the_o square_n of_o the_o line_n ab_fw-la which_o be_v prove_v equal_a to_o the_o square_n of_o the_o line_n lm_o be_v double_a to_o the_o square_n of_o the_o line_n bd_o which_o be_v also_o equal_a to_o the_o square_n of_o the_o line_n le._n this_o corollary_n be_v the_o 16._o proposition_n of_o the_o 14._o book_n after_o campane_n first_o part_n of_o the_o demonstration_n second_o part_n of_o the_o construction_n second_o part_n of_o the_o demonstration_n demonstration_n by_o the_o 2._o assumpt_v 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of_o the_o dodecahedron_n that_o 3._o square_n of_o the_o line_n fb_o be_v great_a they_o 6._o square_n of_o the_o line_n nb._n that_o there_o can_v be_v no_o other_o solid_a beside_o these_o five_o contain_v under_o equilater_n and_o equiangle_n base_n that_o the_o angle_n of_o a_o equilater_n and_o equiangle_n pentagon_n be_v one_o right_a angle_n and_o a_o 〈◊〉_d part_n 〈◊〉_d which_o thing_n be_v also_o before_o prove_v in_o the_o 〈◊〉_d of_o the_o 32._o of_o the_o ●irst_n the_o side_n of_o the_o angle_n of_o the_o incl●●●tion_n of_o the_o 〈◊〉_d of_o the_o 〈◊〉_d be_v 〈◊〉_d rational_a the_o side_n of_o the_o angle_n of_o the_o inclination_n of_o the_o 〈◊〉_d ●f_n t●e_z 〈…〉_o that_o the_o plain_n of_o a_o octohedron_n be_v in_o li●e_z sort_n incline_v that_o the_o plain_n of_o a_o icosahedron_n be_v in_o like_a sort_n incline_v that_o the_o plain_n of_o a_o d●●●●●hedron_n be_v 〈◊〉_d like_o sort_n incline_v the_o side_n of_o the_o angle_n of_o the_o inclination_n of_o the_o supe●ficieces_n of_o the_o tetrahedron_n be_v prove_v rational_a the_o side_n of_o the_o angle_n of_o the_o inclination_n of_o the_o superficiece_n of_o the_o cube_fw-la prove_v rational_a the_o side_n of_o th●_z angle_n etc_n etc_n of_o the_o octohedron_n prove_v rational_a the_o side_n of_o the_o angle_n etc_n etc_n of_o the_o icosahedron_n prove_v irrational_a how_o to_o know_v whether_o the_o angle_n of_o the_o inclination_n be_v a_o right_a angle_n a_o acute_a angle_n or_o a_o oblique_a angle_n the_o argument_n of_o the_o fourteen_o book_n first_o proposition_n after_o flussas_n construction_n demonstration_n demonstration_n this_o be_v manifest_a by_o the_o 12._o proposition_n of_o the_o thirtenh_o book_n as_o campane_n well_o gather_v in_o a_o corollary_n of_o the_o same_o the_o 4._o p●pos●tion_n after_o flussas_n flussas_n this_o be_v afterward_o prove_v in_o the_o 4._o proposition_n this_o assumpt_n be_v the_o 3._o proposition_n after_o flussas_n construction_n of_o the_o assumpt_n demonstration_n of_o the_o assumpt_n construction_n of_o the_o proposition_n demonstration_n of_o the_o proposition_n proposition_n th●_z 5._o proposition_n a●t●r_a 〈◊〉_d construction_n demonstration_n the_o 5._o proposition_n a●ter_a f●ussas_n demonstration_n demonstration_n this_o be_v the_o reason_n of_o the_o corollary_n follow_v a_o corollary_n which_o also_o flussas_n put_v as_o a_o corollary_n after_o the_o 5._o proposition_n in_o his_o order_n the_o 6._o p●●position●●ter_a flussas_n construction_n demonstration_n demonstration_n this_o be_v not_o hard_a to_o prove_v by_o the_o 15._o 16._o and_o 19_o of_o the_o ●●●eth_v ●●●eth_v in_o the_o corollary_n of_o the_o 17._o of_o the_o t●irtenth_o t●irtenth_o 〈◊〉_d again_o be_v require_v the_o assumpt_n which_o be_v afterward_o prove_v in_o this_o 4_o proposition_n proposition_n but_o first_o the_o assumpt_n follow_v the_o construction_n whereof_o here_o begin_v be_v to_o be_v prove_v the_o assumpt_n which_o also_o flussas_n 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we_o have_v be●ore_o note_v demonstration_n demonstration_n in_o the_o 4._o section_n ●f_o this_o proposition_n proposition_n in_o the_o 1._o and_o 3_o section_n of_o the_o same_o proposition_n proposition_n in_o the_o 5._o section_n of_o the_o same_o proposition_n a_o corollary_n the_o first_o proposition_n after_o campane_n construction_n demonstration_n the_o 2._o proposition_n after_o campane_n demonstration_n lead_v to_o a_o impossibility_n the_o 4._o proposition_n after_o campane_n construction_n demonstration_n this_o corollary_n campane_n also_o ●utteth_v after_o the_o 4._o proposition_n in_o his_o order_n the_o 5._o proposition_n after_o campane_n construction_n demonstration_n this_o be_v the_o 6._o and_o 7._o proposition_n after_o campane_n construction_n demonstration_n this_o corollary_n campane_n also_o add_v after_o the_o 7._o proposition_n i●_z his_o order_n the_o 5._o proposition_n a●ter_v campane_n construction_n demonstration_n this_o assumpt_a campane_n also_o have_v after_o the_o 8._o proposition_n in_o his_o order_n construction_n demonstration_n the_o 9_o proposition_n after_o campane_n construction_n demonstration_n this_o campane_n put_v a●_z a_o corollary_n in_o the_o 9_o proposition_n after_o his_o order_n this_o corollary_n be_v the_o 9_o proposition_n after_o campane_n the_o 12._o proposition_n after_o campane_n construction_n demonstration_n the_o 13._o proposition_n after_o campane_n the_o 14._o proposition_n after_o campane_n demonstration_n of_o the_o first_o part_n demonstration_n of_o the_o second_o part_n the_o 17._o proposition_n after_o campane_n fir●t_o part_n of_o the_o construction_n first_o part_n of_o the_o demonstration_n second_o par●_n of_o the_o construction_n second_o part_n of_o the_o demonstration_n the_o 18._o proposition_n after_o campane_n demonstration_n of_o the_o first_o part_n demonstration_n of_o the_o second_o part_n the_o corollary_n of_o the_o 8._o proposition_n after_o campane_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n the_o argument_n of_o the_o 15._o book_n book_n in_o this_o proposition_n as_o also_o in_o all_o the_o other_o follow_v by_o the_o name_n of_o a_o pyramid_n understand_v a_o tetrahedron_n as_o i_o have_v before_o admonish_v construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n that_o which_o here_o follow_v concern_v the_o inclination_n of_o the_o plain_n of_o the_o five_o solid_n be_v before_o teach_v ●hough_o not_o altogether_o after_o the_o same_o manner_n out_o of_o flussas_n in_o the_o latter_a ●nde_n of_o the_o 13_o book_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n first_o part_n of_o the_o construction_n first_o part_n of_o the_o demonstration_n second_o part_n of_o the_o construction_n second_o part_n of_o the_o demonstration_n three_o part_n of_o the_o construction_n three_o part_n of_o the_o demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n produce_v in_o the_o figure_n the_o line_n tf_n to_o the_o point_n b._n construction_n demonstration_n this_o proposition_n campane_n have_v &_o be_v the_o last_o also_o in_o order_n of_o the_o 15._o book_n with_o he_o the_o argument_n of_o the_o 16._o book_n construction_n demonstration_n demonstration_n by_o a_o pyramid_n understand_v a_o tetrahedron_n throughout_o all_o this_o book_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n construction_n demonstration_n demonstration_n that_o be_v a●_z 18._o to_o 1._o demonstration_n demonstration_n that_o i●_z as_o 9_o to_o 2._o 2._o that_o be_v as_o 18._o to_o 2._o or_o 9_o to_o 1._o draw_v in_o the_o figure_n a_o line_n from_o b_o to_o h._n h._n what_o the_o duple_n of_o a_o extreme_a and_o mean_a proportion_n be_v construction_n demonstration_n demonstration_n constrution_n demonstration_n construction_n demonstration_n demonstration_n demonstration_n that_o be_v at_o 13._o 1_o ●_o be_v to●_n ●_z demonstration_n demonstration_n construction_n demonstration_n construction_n demonstration_n extend_v in_o the_o figure_n a_o line_n ●rom_o the_o point_n e_o to_o the_o point_n b._n extend_v in_o the_o figure_n a_o line_n from_o the_o point_n e_o to_o the_o point_n b._n demonstration_n construction_n demonstration_n second_o part_n of_o the_o demonstration_n icosidodecahedron_n exoctohedron_n that_o the_o exoctohedron_n be_v contain_v in_o a_o sphere_n that_o the_o exoctohedron_n be_v contain_v in_o the_o sphere_n give_v that_o the_o dia●●●ter_n of_o the_o sphere_n be_v do●ble_a to_o the_o side_n ●f_o the_o exoctohedron_n that_o the_o icosidodecahedron_n be_v contain_v in_o the_o sphere_n give_v give_v that_o be_v as_o 8._o 103●_n ●_z fault_n escape_v ●cl_n ●ag_n line_n faultes●_n co_n 〈◊〉_d 〈◊〉_d  _o  _o  _o errata_fw-la lib._n 1._o  _o 1_o 2_o 41_o point_n b._n at_o campane_n point_n c_o a●_z campane_n 3_o 1_o 22_o a●l_a line_n draw_v all_o righ●_n 〈…〉_o 3_o 1_o 28_o line_n draw_v to_o the_o superficies_n right_a line_n draw_v to_o the_o circumference_n 9_o 1_o 42_o li●es_n ab_fw-la and_o ac_fw-la line_n ab_fw-la and_o bc_o 15_o 1_o 35_o be_v equal_a be_v prove_v equal_a 20_o 2_o 28_o by_o the_o first_o by_o the_o four_o 21_o 1_o 39_o t●e_z centre_n c._n the_o centre_n e_o 2d_o 2_o ●_o i●●ower_a right_n if_o two_o right_a 25_o 2_o 3_o f●●●_n petition_n five_o petition_n 49_o 2_o 7_o 14._o ●●_o 32.64_o etc_n etc_n 4.8.16.32.64_o &_o 53_o 1_o 39_o the_o triangle_n ng_z the_o triangle_n k●_n 54_o 2_o 25_o by_o the_o 44_o by_o the_o 42_o 57_o 2_o 23_o and_o c●g_v in_o the_o and_o cgb_n be_v th●_z  _o  _o  _o in_o stead_n of_o ●lussates_n through_o out_o 〈◊〉_d whole_a book_n read_v ●lus●as_v  _o  _o  _o errata_fw-la lib._n 2._o  _o 60_o 2_o 29_o gnomon_n fgeh_a gnomon_n ahkd_v  _o  _o 30_o gnomon_n ehfg_n gnomon_n ●ckd_v 69_o 1_o 18_o the_o whole_a line_n the_o whole_a ●igure_n 76_o 2_o 9_o the_o diameter_n cd_o the_o diameter_n ahf_n  _o  _o  _o errata_fw-la lib._n 3._o  _o 82_o 2_o 36_o angle_n equal_a to_o the_o angle_n 92_o 1_o last_o the_o line_n ac_fw-la be_v the_o line_n of_o 〈◊〉_d  _o  _o  _o errata_fw-la lib._n 4._o  _o 110_o 2_o 10_o cd_o touch_v the_o ed_z touch_v the_o  _o  _o 12_o side_n of_o the_o other_o angle_n of_o the_o other_o 115_o 1_o 21_o and_o hb_o and_o he_o 117_o 2_o 44_o the_o angle_n acd_o the_o angle_n acb_o 118_o 1_o 2_o into_o ten_o equal_a into_o two_o equal_a 121_o 1_o 3●_o cd_o and_o ea_fw-la cd_o de_fw-fr &_o ea_fw-la ●●●_o 1_o 29_o the_o first_o the_o three_o  _o  _o  _o errata_fw-la lib._n 5._o  _o 126_o 1_o 43_o it_o make_v 12._o more_o than_o 17._o by_o 5._o it_o make_v 24._o more_o than_o 17._o by_o 7._o 129_o 1_n  _o in_o stead_n of_o the_o figure_n of_o the_o 6._o definition_n draw_v in_o the_o mag●●_n a_o figure_n like_o unto_o th●s_n 134_o 2_o 4_o as_o ab_fw-la be_v to_o a_o so_o be_v cd_o to_o c_o as_z ab_fw-la be_v to_o b_o so_o be_v cd_o to_o d_o 141_o 2_o last_v but_o if_o king_n exceed_v m_o but_o if_o h_o exceed_v m_o lief_a be_v death_n and_o death_n be_v lief_a aetatis_fw-la svae_fw-la xxxx_n at_o london_n print_v by_o john_n day_n dwell_v over_o aldersgate_n beneath_o saint_n martins_n ¶_o these_o book_n be_v to_o be_v sell_v at_o his_o shop_n under_o the_o gate_n 1570._o
the_o lengthe_n of_o day_n and_o night_n the_o hour_n and_o time_n both_o night_n and_o day_n be_v know_v with_o very_a many_o other_o pleasant_a and_o necessary_a use_n whereof_o some_o be_v know_v but_o better_a remain_v for_o such_o to_o know_v and_o use_v who_o of_o a_o spark_n of_o true_a fire_n can_v make_v a_o wonderful_a bonfire_n by_o apply_v of_o due_a matter_n due_o ☜_o of_o astrology_n here_o i_o make_v a_o ar●e_n several_a from_o astronomie●_n ●_z not_o by_o new_a devise_n but_o by_o good_a reason_n and_o authority_n for_o astrology_n be_v a_o art_n mathematical_a which_o reasonable_o demonstrate_v the_o operation_n and_o effect_n of_o the_o natural_a beam_n of_o light_n and_o secret_a influence_n of_o the_o star_n and_o planet_n in_o every_o element_n and_o elemental_a body_n at_o all_o time_n in_o any_o horizon_n assign_v this_o art_n be_v furnish_v with_o many_o other_o great_a art_n and_o experience_n as_o with_o perfect_v perspective_n astronomy_n cosmography_n 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and_o therefore_o say_v aristotle_n in_o the_o first_o of_o his_o meteorological_a book_n in_o the_o second_o chapter_n est_fw-la autem_fw-la necessariò_fw-la mundus_fw-la iste_fw-la supernis_fw-la lationibus_fw-la ferè_fw-la continuus_fw-la ut_fw-la inde_fw-la vis_fw-la eius_fw-la universa_fw-la regatur_fw-la ea_fw-la siquidem_fw-la causa_fw-la prima_fw-la putanda_fw-la omnibus_fw-la est_fw-la unde_fw-la motus_fw-la principium_fw-la existit_fw-la that_o be_v this_o elemental_a world_n be_v of_o necessity_n almost_o next_o adjoin_v to_o the_o heavenly_a motion_n that_o from_o thence_o all_o his_o virtue_n or_o force_n may_v be_v govern_v for_o that_o be_v to_o be_v think_v the_o first_o cause_n unto_o all_o from_o which_o the_o beginning_n of_o motion_n be_v and_o again_o in_o the_o ten_o chapter_n op●rtet_fw-la igitur_fw-la &_o horum_fw-la principia_fw-la sumamus_fw-la &_o causas_fw-la omnium_fw-la similiter_fw-la principium_fw-la igitur_fw-la vy_z movens_fw-la praecipuumque_fw-la &_o omnium_fw-la primum_fw-la circulus_fw-la ille_fw-la est_fw-la in_fw-la quo_fw-la manifest_a solis_fw-la latio_fw-la etc_n etc_n and_o so_o forth_o his_o meteorological_a book_n be_v full_a of_o argument_n and_o effectual_a demonstration_n of_o the_o virtue_n operation_n and_o power_n of_o the_o heavenly_a body_n in_o and_o upon_o the_o four_o element_n and_o other_o body_n of_o they_o either_o perfect_o or_o unperfect_o compose_v and_o in_o his_o second_o book_n de_fw-fr generatione_fw-la &_o corruption_n in_o the_o ten_o chapter_n quocirca_fw-la &_o prima_fw-la lati●_n or●us_n &_o interitus_fw-la causa_fw-la non_fw-la est_fw-la sed_fw-la obliqui_fw-la circuli_fw-la latio_fw-la ea_fw-la namque_fw-la &_o continua_fw-la est_fw-la &_o dvobus_fw-la motibus_fw-la fit_a in_o english_a thus_o wherefore_o the_o uppermost_a motion_n be_v not_o the_o cause_n of_o generation_n and_o corruption_n but_o the_o motion_n of_o the_o zodiac_n for_o that_o both_o be_v continual_a and_o be_v cause_v of_o two_o move_n and_o in_o his_o second_o book_n and_o second_o chapter_n of_o his_o physike_n homo_fw-la namque_fw-la generate_fw-la hominem_fw-la atque_fw-la sol._n for_o man_n say_v he_o and_o the_o son_n be_v cause_n of_o man_n generation_n authority_n may_v be_v bring_v very_o many_o both_o of_o 1000_o 2000_o yea_o and_o 3000._o year_n antiquity_n of_o great_a philosopher_n expert_a wise_a and_o godly_a man_n for_o that_o conclusion_n which_o daily_a and_o hourly_o we_o man_n may_v discern_v and_o perceive_v by_o sense_n and_o reason_n all_o beast_n do_v feel_v and_o simple_o show_v by_o their_o action_n and_o passion_n outward_a and_o inward_a all_o plant_n herb_n tree_n flower_n and_o fruit_n and_o final_o the_o element_n and_o all_o thing_n of_o the_o element_n compose_v do_v geve_v testimony_n as_o aristotle_n say_v that_o their_o whole_a disposition_n virtue_n and_o natural_a motion_n depend_v of_o the_o activity_n of_o the_o heavenly_a motion_n and_o influence_n whereby_o beside_o the_o specifical_a order_n and_o form_n due_a to_o every_o seed_n and_o beside_o the_o nature_n proper_a to_o the_o individual_a matrix_fw-la of_o the_o thing_n produce_v what_o shall_v be_v the_o heavenly_a impression_n the_o perfect_a and_o circumspect_a astrologien_n have_v to_o conclude_v not_o only_o by_o apotelesme_n 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d but_o by_o natural_a and_o mathematical_a demonstration_n 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d whereunto_o what_o science_n be_v requisite_a without_o exception_n i_o partly_o have_v here_o warn_v and_o in_o my_o brop●de●●●●_n beside_o other_o matter_n there_o disclose_v i_o have_v mathematical_o furnish_v up_o the_o whole_a method_n to_o this_o our_o age_n not_o so_o careful_o handle_v by_o any_o that_o ever_o i_o see_v or_o hear_v of_o i_o be_v for_o lovayn_n ●1_n year_n ago_o by_o certain_a earnest_a disputation_n of_o the_o learned_a g●●ardus_n m●rc●t●●_n and_o 〈◊〉_d goga●a_n and_o other_o thereto_o so_o provoke_v and_o by_o my_o constant_a and_o invincible_a zeal_n to_o the_o verity_n in_o observation_n of_o heavenly_a influence_n to_o the_o min●te_n of_o time_n than_o so_o diligent_a and_o chief_o by_o the_o supernatural_a influence_n from_o the_o star_n of_o jacob_n so_o direct_v that_o any_o modest_a and_o sober_a student_n careful_o and_o diligent_o sel●ing_v for_o the_o truth_n will_v both_o find_v &_o confess_v therein_o to_o be_v the_o verity_n of_o these_o my_o word_n and_o also_o become_v a_o reasonable_a reformer_n of_o three_o sort_n of_o people_n about_o these_o influential_a operation_n great_o err_v from_o the_o truth_n whereof_o the_o one_o be_v light_a believer_n the_o other_o note_n light_a despiser_n and_o the_o three_o light_a practiser_n the_o first_o &_o most_o common_a sort_n think_v the_o heaven_n and_o star_n to_o be_v answerable_a to_o any_o their_o doubt_n or_o desire_n which_o be_v not_o so_o and_o in_o deed_n they_o to_o much_o over_o reach_n the_o second_o sort_n think_v no_o 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elephant_n do_v as_o the_o cynocephalus_n as_o the_o porpentine_n do●h_v nor_o will_v allow_v these_o perfect_a and_o incorruptible_a mighty_a body_n so_o much_o virtual_a radiation_n &_o force_n as_o they_o see_v in_o a_o little_a piece_n of_o a_o magnes_n stone_n which_o at_o great_a distance_n show_v his_o operation_n and_o perchance_o they_o think_v the_o sea_n &_o rivers_n as_o the_o thames_n to_o be_v some_o quick_a thing_n and_o s●_n to_o ebb_v a●d_z slow_a run_v in_o and_o out_o of_o themselves_o at_o ●hei●_n own_o fantasy_n god_n help_v god_n help_v sure_o these_o man_n come_v to_o short_a and_o either_o be_v to_o dull_a or_o wilful_o blind_a or_o perhaps_o to_o malicious_a the_o three_o man_n be_v the_o common_a and_o vulgar_a astrologien_n or_o practiser_n who_o be_v not_o due_o artificial_o and_o perfect_o furnish_v yet_o either_o for_o vain_a glory_n or_o gain_v or_o like_o a_o simple_a dolt_n &_o blind_a bayard●_n both_o in_o matter_n and_o manner_n err_v to_o the_o discredit_n of_o the_o wary_a and_o modest_a astrologien_n and_o to_o the_o rob_n of_o those_o most_o noble_a corporal_a
be_v wood_n copper_n tin_n lead_v silver_n etc_n etc_n be_v as_o i_o say_v of_o like_a nature_n condition_n and_o like_o weight_n throughout_o and_o you_o may_v by_o say_v balance_n have_v prepare_v a_o great_a number_n of_o the_o small_a weight_n which_o by_o those_o balance_n can_v be_v discern_v or_o try_v and_o so_o have_v proceed_v to_o make_v you_o a_o perfect_a pyle_z company_n &_o number_n of_o weight_n to_o the_o weight_n of_o six_o eight_o or_o twelve_o pound_n weight_n most_o diligent_o try_v all_o and_o of_o every_o one_o the_o content_a know_v in_o your_o least_o weight_n that_o be_v wayable_a they_o that_o can_v not_o have_v these_o weight_n of_o preciseness_n may_v by_o sand_n uniform_a and_o well_o dust_v make_v they_o a_o number_n of_o weight_n somewhat_o never_o preciseness_n by_o half_v ever_o the_o sand_n they_o shall_v at_o length_n come_v to_o a_o least_o common_a weight_n therein_o i_o leave_v the_o far_a matter_n to_o their_o discretion_n who_o need_n shall_v pinch_n the_o venetian_n consideration_n of_o weight_n may_v seem_v precise_a enough_o d._n by_o eight_o descent_n progressionall_a grain_n half_v from_o a_o grain_n your_o cube_n sphere_n apt_a balance_n and_o convenient_a weight_n be_v ready_a fall_v to_o work_v ●_o first_o way_n your_o cube_n note_v the_o number_n of_o the_o weight_n way_n after_o that_o your_o sphere_n note_v likewise_o the_o number_n of_o the_o weight_n if_o you_o now_o find_v the_o weight_n of_o your_o cube_n to_o be_v to_o the_o weight_n of_o the_o sphere_n as_o 21._o be_v to_o 11_o then_o you_o see_v how_o the_o mechanicien_n and_o experimenter_n without_o geometry_n and_o demonstration_n be_v as_o near_o in_o effect_n teach_v the_o proportion_n of_o the_o cube_n to_o the_o sphere_n as_o i_o have_v demonstrate_v it_o in_o the_o end_n of_o the_o twelve_o book_n of_o euclid_n often_o try_v with_o the_o same_o cube_n and_o sphere_n then_o change_n your_o sphere_n and_o cube_n to_o a_o other_o matter_n or_o to_o a_o other_o bigness_n till_o you_o have_v make_v a_o perfect_a universal_a experience_n of_o it_o possible_a it_o be_v that_o you_o shall_v win_v to_o near_a term_n in_o the_o proportion_n when_o you_o have_v find_v this_o one_o certain_a drop_n of_o natural_a verity_n proceed_v on_o to_o infer_v and_o due_o to_o make_v assay_n of_o matter_n depend_v as_o because_o it_o be_v well_o demonstrate_v that_o a_o cylinder_n who_o heith_n and_o diameter_n of_o his_o base_a be_v equal_a to_o the_o diameter_n of_o the_o sphere_n be_v sesquialter_fw-la to_o the_o same_o sphere_n that_o be_v as_o 3._o to_o 2_o to_o the_o number_n of_o the_o weight_n of_o the_o sphere_n add_v half_o so_o much_o as_o it_o be_v and_o so_o have_v you_o the_o number_n of_o the_o weight_n of_o that_o cylinder_n which_o be_v also_o comprehend_v of_o our_o former_a cube_n so_o that_o the_o base_a of_o that_o cylinder_n be_v a_o circle_n describe_v in_o the_o square_a which_o be_v the_o base_a of_o our_o cube_n but_o the_o cube_n and_o the_o cylinder_n be_v both_o of_o one_o heith_n have_v their_o base_n in_o the_o same_o proportion_n in_o the_o which_o they_o be_v one_o to_o a_o other_o in_o their_o massine_n or_o solidity_n but_o before_o we_o have_v two_o number_n express_v their_o massine_n solidity_n and_o quantity_n by_o weight_n wherefore_o we_o have_v inscribe_v the_o proportion_n of_o the_o square_n to_o the_o circle_n inscribe_v in_o the_o same_o square_n and_o so_o be_v we_o fall_v into_o the_o knowledge_n sensible_a and_o experimental_a of_o archimedes_n great_a secret_n of_o he_o by_o great_a travail_n of_o mind_n seek_v and_o find_v wherefore_o to_o any_o circle_n give_v you_o can_v give_v a_o square_n equal_a mechanical_o as_o i_o have_v teach_v in_o my_o annotation_n upon_o the_o first_o proposition_n of_o the_o twelve_o book_n and_o likewise_o to_o any_o square_n give_v you_o may_v give_v a_o circle_n equal_a 〈…〉_o if_o you_o describe_v a_o circle_n which_o shall_v be_v in_o that_o 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overplus_n of_o the_o square_n you_o shall_v then_o weigh_v your_o circle_n see_v whether_o the_o weight_n of_o the_o square_n be_v to_o your_o circle_n as_o 14._o to_o 11._o as_o i_o have_v note_a in_o the_o begin_n of_o euclides_n twelve_o book_n etc_n etc_n after_o this_o resort_n to_o my_o last_o proposition_n upon_o the_o last_o of_o the_o twelve_o and_o there_o help_v yourself_o to_o the_o end_n and_o here_o note_v this_o diameter_n by_o the_o way_n that_o we_o may_v square_a the_o circle_n without_o have_v knowledge_n of_o the_o proportion_n of_o the_o circumference_n to_o the_o diameter_n as_o you_o have_v here_o perceive_v and_o otherways_o also_o i_o can_v demonstrate_v it_o so_o that_o many_o have_v cumberd_v themselves_o superfluous_o by_o travail_v in_o that_o point_n first_o which_o be_v not_o of_o necessity_n first_o and_o also_o very_o intricate_a and_o easy_o you_o may_v and_o that_o diverse_o come_v to_o the_o knowledge_n of_o the_o circumference_n the_o circle_n quantity_n be_v first_o know_v which_o thing_n i_o leave_v to_o your_o consideration_n make_v haste_n to_o dispatch_v a_o other_o magistral_a problem_n and_o to_o bring_v it_o near_o to_o your_o knowledge_n and_o ready_a deal_n with_o than_o the_o world_n before_o this_o day_n have_v it_o for_o you_o that_o i_o can_v tell_v of_o and_o that_o be_v a_o mechanical_a double_a of_o the_o cube_n etc_n etc_n mathematical_a which_o may_v thus_o be_v do_v make_v of_o copper_n plate_n or_o tyn_n plate_n a_o foursquare_n upright_o pyramid_n or_o a_o cone_n perfect_o fashion_v in_o the_o hollow_a within_o wherein_o let_v great_a diligence_n be_v use_v to_o approach_v as_o never_o as_o may_v be_v to_o the_o mathematical_a perfection_n of_o those_o figure_n at_o their_o base_n let_v they_o be_v all_o open_a every_o where_o else_o most_o close_o and_o just_a to_o from_o the_o vertex_fw-la to_o the_o circumference_n of_o the_o base_a of_o the_o cone_n &_o to_o the_o side_n of_o the_o base_a of_o the_o pyramid_n let_v 4._o straight_a line_n be_v draw_v in_o the_o inside_n of_o the_o cone_n and_o pyramid_n squall_v make_v at_o their_o fall_n on_o the_o perimeter_n of_o the_o base_n equal_a angle_n on_o both_o side_n themselves_o with_o the_o say_a perimeter_n these_o 4._o line_n in_o the_o pyramid_n and_o as_o many_o in_o the_o cone_n divide_v one_o in_o 12._o equal_a part_n and_o a_o other_o in_o 24._o a_o other_o in_o 60_o and_o a_o other_o in_o 100_o reckon_v up_o from_o the_o vertex_fw-la or_o use_v other_o number_n of_o division_n d._n as_o experience_n shall_v reach_v you●_n then_o 〈◊〉_d set_v your_o cone_n or_o pyramid_n with_o the_o vertex_fw-la downward_o perpendicular_o in_o respect_n of_o the_o base_a though_o it_o be_v otherways_o it_o hinder_v nothing_o so_o let_v they_o most_o steady_o be_v stay_v now_o if_o there_o be_v a_o cube_n which_o you_o will_v have_v double_v make_v you_o a_o pretty_a cube_n of_o copper_n silver_n lead_v tin_n wood_n stone_n or_o bone._n or_o else_o make_v a_o hollow_a cube_n or_o cubi●_n coffin_n of_o copper_n silver_n tin_n or_o wood_n etc_n etc_n these_o you_o may_v so_o proportion_v in_o respect_n of_o your_o pyramid_n or_o cone_n that_o the_o pyramid_n or_o cone_n will_v be_v able_a to_o contain_v the_o weight_n of_o they_o in_o wa●●_n 3._o or_o 4._o time_n at_o the_o least_o what_o stuff_n so_o ever_o they_o be_v make_v of●_n let_v not_o your_o solid_a angle_n at_o the_o vertex_fw-la be_v to_o sharp_a but_o that_o the_o water_n may_v come_v with_o ease_n to_o the_o very_a vertex_fw-la of_o your_o hollow_a cone_n or_o pyramid_n put_v one_o of_o your_o solid_a cube_n in_o a_o balance_n apt_a d._n take_v the_o weight_n thereof_o exact_o in_o water_n pour_v that_o water_n without_o loss_n into_o the_o hollow_a pyramid_n or_o cone_n quiet_o
be_v c●_n demonstration_n now_o be_v the_o parallelogram_n ae_n equal_a to_o the_o parallelogram_n of_o and_o ce_fw-fr by_o the_o first_o of_o this_o book_n but_o ae_n be_v the_o square_n make_v of_o ab_fw-la and_o of_o be_v the_o rectangle_n parallelogram_n comprehend_v under_o the_o line_n basilius_n and_o ac_fw-la for_o it_o be_v comprehend_v under_o the_o line_n dam_n and_o ac_fw-la but_o the_o line_n ad_fw-la be_v equal_a unto_o the_o line_n ab_fw-la and_o likewise_o the_o parrallelogramme_n ce_fw-fr be_v equal_a to_o that_o which_o be_v contain_v under_o the_o line_n ab_fw-la and_o bc_o for_o the_o line_n be_v be_v equal_a unto_o the_o line_n ab_fw-la wherefore_o that_o which_o be_v contain_v under_o basilius_n and_o ac_fw-la together_o with_o that_o which_o be_v contain_v under_o the_o line_n ab_fw-la and_o bc_o be_v equal_a to_o the_o square_n make_v of_o the_o line_n ab_fw-la if_o therefore_o a_o right_a line_n be_v divide_v by_o chance_n the_o rectangle_n figure_n which_o be_v comprehend_v under_o the_o whole_a and_o every_o one_o of_o the_o part_n be_v equal_a to_o the_o square_n which_o be_v make_v of_o the_o whole_a which_o be_v require_v to_o be_v demonstrate_v an_o other_o demonstration_n of_o campane_n suppose_v that_o the_o line_n ab_fw-la be_v divide_v into_o the_o line_n ac_fw-la cd_o and_o db._n then_o i_o say_v that_o the_o square_a of_o the_o whole_a line_n ab_fw-la which_o let_v be_v aebf_n be_v equal_a to_o the_o rectangle_n figure_n which_o be_v contain_v under_o the_o whole_a and_o every_o one_o of_o the_o part_n for_o take_v the_o line_n king_n which_o let_v be_v equal_a to_o the_o line_n a_o b._n now_o then_o by_o the_o first_o proposition_n the_o rectangle_n figure_n contain_v under_o the_o line_n ab_fw-la and_o king_n be_v equal_a to_o the_o rectangle_n figure_v contain_v under_o the_o line_n king_n and_o all_o the_o part_n of_o the_o line_n ab_fw-la but_o that_o which_o be_v contain_v under_o the_o line_n king_n and_o ab_fw-la be_v 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proposition_n barlaam_n if_o a_o number_n give_v be_v divide_v into_o two_o other_o number_n the_o superficial_a number_n which_o be_v produce_v of_o the_o multiplication_n of_o the_o whole_a into_o either_o part_n add_v together_o be_v equal_a to_o the_o square_a number_n of_o the_o whole_a number_n give_v suppose_v that_o the_o number_n give_v by_o ab_fw-la and_o let_v it_o be_v divide_v into_o two_o other_o number_n ac_fw-la and_o cb._n then_o i_o say_v that_o the_o two_o superficial_a number_n which_o be_v produce_v of_o the_o multiplication_n of_o ab_fw-la into_o ac_fw-la and_o of_o ab_fw-la into_o bc_o those_o two_o superficial_a number_n i_o say_v be_v add_v together_o shall_v be_v equal_a to_o the_o square_a number_n produce_v of_o the_o multiplication_n of_o the_o number_n ab_fw-la into_o itself_o for_o let_v the_o number_n ab_fw-la multiply_v itself_o produce_v the_o number_n d._n let_v the_o number_n ac_fw-la also_o multiply_v the_o number_n ab_fw-la produce_v the_o number_n of_o again_o let_v the_o number_n cb_o multipli_v the_o self_n same_o number_n ab_fw-la produce_v the_o number_n fg._n now_o forasmuch_o as_o the_o number_n ac_fw-la multiply_v the_o number_n ab_fw-la produce_v the_o number_n of_o therefore_o the_o number_n ab_fw-la measure_v the_o number_n of_o by_o the_o unity_n which_o be_v in_o ac_fw-la again_o forasmuch_o as_o the_o number_n cb_o multiply_v the_o number_n ab_fw-la and_o produce_v the_o number_n fg_o therefore_o the_o number_n ab_fw-la measure_v the_o number_n fg_o by_o the_o unity_n which_o be_v in_o the_o number_n cb._n but_o the_o same_o number_n ab_fw-la before_o measure_a the_o number_n of_o by_o the_o unity_n which_o be_v in_o the_o number_n ac_fw-la wherefore_o the_o number_n ab_fw-la measure_v the_o whole_a number_n ●g_z by_o the_o unity_n which_o be_v in_o ab_fw-la far_o forasmuch_o as_o the_o number_n ab_fw-la multiply_v itself_o produce_v the_o number_n d_o therefore_o the_o number_n ab_fw-la measure_v the_o number_n d_o by_o the_o unity_n which_o be_v in_o himself_o wherefore_o it_o measure_v either_o of_o these_o number_n namely_o the_o number_n d_o and_o the_o number_n eglantine_n by_o the_o unity_n which_o be_v in_o himself_o wherefore_o how_o multiplex_n the_o number_n d_o be_v to_o the_o number_n ab_fw-la so_o multiplex_n be_v the_o number_n eglantine_n to_o the_o same_o number_n ab_fw-la but_o number_n which_o be_v equemultiplices_fw-la to_o one_o and_o the_o self_n same_o number●_n be_v equal_a the_o one_o to_o the_o other_o wherefore_o the_o number_n d_o be_v equal_a to_o the_o number_n eglantine_n and_o the_o number_n d_o be_v the_o square_a number_n make_v of_o the_o number_n ab_fw-la and_o the_o number_n eglantine_n be_v compose_v of_o the_o two_o superficial_a number_n produce_v of_o ab_fw-la into_o bc_o and_o of_o basilius_n into_o ac_fw-la wherefore_o the_o square_a number_n produce_v of_o the_o number_n ab_fw-la be_v equal_a to_o the_o superficial_a number_n produce_v of_o the_o 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46._o of_o the_o first_o upon_o the_o line_n be_v square_a cdeb_n and_o by_o the_o second_o petition_n extend_v ed_z unto_o f._n and_o by_o the_o point_n a_o draw_v by_o the_o 31._o of_o the_o first_o a_o line_n parallel_n unto_o either_o of_o these_o line_n cd_o and_o be_v and_o let_v the_o same_o be_v af._n now_o the_o parallelogram_n ae_n be_v equal_a unto_o the_o parallelogram_n ad_fw-la and_o ce._n demonstration_n and_o ae_n be_v the_o rectangle_n figure_n comprehend_v under_o the_o line_n ab_fw-la and_o bc._n for_o it_o be_v comprehend_v under_o the_o line_n ab_fw-la and_o be_v which_o line_n be_v be_v equal_a unto_o the_o line_n bc._n and_o the_o parallelogram_n ad_fw-la be_v equal_a to_o that_o which_o be_v contain_v under_o the_o line_n ac_fw-la and_o cb_o for_o the_o line_n dc_o be_v equal_a unto_o the_o line_n cb_o and_o db_o be_v the_o square_n which_o be_v make_v of_o the_o line_n cb._n wherefore_o the_o rectangle_n figure_n comprehend_v under_o the_o line_n ab_fw-la and_o bc_o be_v equal_a to_o the_o rectangle_n figure_n comprehend_v under_o the_o line_n ac_fw-la and_o cb_o &_o also_o unto_o the_o square_n which_o be_v make_v of_o the_o line_n bc._n if_o therefore_o a_o right_a line_n be_v divide_v by_o chance_n the_o rectangle_n figure_n comprehend_v under_o the_o whole_a and_o one_o of_o the_o part_n be_v equal_a to_o the_o rectangle_n figure_n comprehend_v under_o the_o part_n and_o unto_o the_o square_n which_o be_v make_v of_o the_o foresay_a part_n which_o be_v require_v to_o be_v prove_v a_o example_n of_o this_o proposition_n in_o number_n suppose_v a_o number_n namely_o 14._o to_o be_v divide_v into_o two_o part_n 8._o and_o 6._o the_o whole_a number_n 14._o multiply_v into_o 8._o one_o of_o his_o part_n produce_v 112_o the_o part_n 8._o &_o 6._o multiply_v the_o one_o into_o the_o other_o produce_v 48_o which_o add_v to_o 64_o which_o be_v the_o square_a of_o 8._o the_o
poligonon_n figure_n of_o 24._o side_n likewise_o of_o the_o hexagon_n ab_fw-la and_o of_o the_o pentagon_n ac_fw-la shall_v be_v make_v a_o poligonon_n figure_n of_o 30._o side_n one_o of_o who_o side_n shall_v subtend_v the_o ark_n bc._n for_o the_o denomination_n of_o ab_fw-la which_o be_v 6._o exceed_v the_o denomination_n of_o ac_fw-la which_o be_v 5._o only_a by_o unity_n so_o also_o forasmuch_o as_o the_o denomination_n of_o ab_fw-la which_o be_v 6._o exceed_v the_o denomination_n of_o ae_n which_o be_v 3._o by_o 3._o therefore_o the_o ark_n be_v shall_v contain_v 3._o side_n of_o a_o poligonon_n figure_n of_o .18_o side_n and_o observe_v this_o self_n same_o method_n and_o order_n a_o man_n may_v find_v out_o infinite_a side_n of_o a_o poligonon_n figure_n the_o end_n of_o the_o four_o book_n of_o euclides_n element_n ¶_o the_o five_o book_n of_o euclides_n element_n this_o five_o book_n of_o euclid_n be_v of_o very_o great_a commodity_n and_o use_n in_o all_o geometry_n book_n 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multiplex_fw-la superperticular_a and_o multiplex_fw-la superpartiens_fw-la multiplex_fw-la be_v when_o the_o antecedent_n contain_v in_o itself_o the_o consequent_a certain_a time_n without_o more_o or_o less_o multiplex_fw-la as_o twice_o thrice_o four_o time_n and_o so_o far_o and_o this_o proportion_n have_v under_o it_o infinite_a kind_n for_o if_o the_o antecedent_n contain_v the_o consequent_a just_o twice_o it_o be_v call_v dupla_fw-la proportion_n proportion_n as_o 4_o to_o 2._o if_o thrice_o tripla_fw-la quintuple_a as_o 9_o to_o 3._o if_o 4._o time_n quadrupla_fw-la as_o 12._o to_o 3._o if_o 5._o time_n quintupla_fw-la as_o 15._o to_o 3._o and_o so_o infinite_o after_o the_o same_o manner_n superperticular_a superperticular_a be_v when_o the_o antecedent_n contain_v the_o consequent_a only_o once_o &_o moreover_o some_o one_o part_n thereof_o as_o a_o half_a a_o three_o or_o four_o etc_n etc_n this_o kind_n also_o have_v under_o it_o infinite_a kind_n for_o if_o the_o antecedent_n contain_v the_o consequent_a once_o and_o a_o half_a thereof_o it_o be_v call_v sesquialtera_fw-la sesquialtera_fw-la as_o 6._o to_o 4_o if_o once_o and_o a_o three_o part_n sesquitertia_fw-la sesquitertia_fw-la as_o 4._o to_o 3_o if_o once_o and_o a_o four_o part_n sesquiquarta_fw-la sesquiquarta_fw-la as_o 5._o to_o 4._o and_o so_o in_o like_a manner_n infinite_o superpartiens_fw-la superpartiens_fw-la be_v when_o the_o antecedent_n contain_v the_o consequent_a only_o once_o &_o moreover_o more_o part_n than_o one_o of_o the_o same_o as_o two_o three_o three_o fourthe_n four_o fifthe_n and_o so_o forth_o this_o also_o have_v infinite_a kind_n under_o it_o for_o if_o the_o antecedent_n contain_v above_o the_o consequent_a two_o part_n it_o be_v call_v superbipartiens_fw-la superbipartiens_fw-la as_o 7._o to_o 5._o if_o 3._o part_n supertripartiens_fw-la as_o 7._o to_o 4._o supertripartiens_fw-la if_o 4._o part_n superquadripartiens_n superquadripartiens_fw-la as_o 9_o to_o 5._o if_o 5._o part_n superquintipartiens_n as_o 11._o to_o 6._o superquintipartiens_fw-la and_o so_o forth_o infinite_o superperticular_a multiplex_fw-la superperticular_a be_v when_o the_o antecedent_n contain_v the_o consequent_a more_o than_o once_o and_o moreover_o only_o one_o part_n of_o the_o same_o this_o kind_n likewise_o have_v infinite_a kind_n under_o it_o for_o if_o the_o antecedent_n contain_v the_o consequent_a twice_o and_o half_o thereof_o it_o be_v call_v dupla_fw-la sesquialtera_fw-la sesquialtera_fw-la as_o 5._o to_o 2._o if_o twice_o and_o a_o three_o dupla_fw-la sesquitertia_fw-la as_o 7._o to_o 3._o sesquitertia_fw-la if_o thrice_o and_o a_o half_a tripla_fw-la sesquialtera_fw-la as_o 7._o to_o 2._o sesquialtera_fw-la if_o four_o time_n and_o a_o half_a quadr●pla_fw-la sesquialtera_fw-la as_o 9_o to_o 2._o and_o so_o go_v on_o infinite_o superpartiens_fw-la multiplex_fw-la superpartient_fw-fr be_v when_o the_o antecedent_n contain_v the_o consequent_a 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denomination_n of_o the_o proportion_n proportion_n which_o in_o the_o first_o kind_n of_o proportion_n namely_o multiplex_n be_v ever_o a_o whole_a number_n and_o in_o all_o other_o kind_n of_o proportion_n it_o be_v a_o break_a number_n as_o if_o you_o will_v know_v the_o denomination_n of_o the_o proportion_n between_o 9_o and_o 3._o divide_v 9_o by_o 3._o so_o shall_v you_o have_v in_o the_o quotient_a 3._o which_o be_v a_o whole_a number_n and_o be_v the_o denomination_n of_o the_o proportion_n and_o show_v that_o the_o proportion_n between_o 9_o &_o 3._o be_v tripla_fw-la so_o the_o proportion_n between_o 12._o and_o 3._o be_v quadrupla_fw-la for_o that_o 12._o be_v divide_v by_o 3._o the_o quotient_n be_v 4._o and_o so_o of_o other_o in_o the_o kind_n of_o multiplex_n and_o although_o in_o this_o kind_a the_o quotient_n be_v ever_o a_o whole_a number_n yet_o proper_o it_o be_v refer_v to_o unity_n and_o so_o be_v represent_v in_o manner_n of_o a_o break_a number_n as_o 5_o ●_o 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denominator_fw-la show_v the_o denomination_n what_o part_n they_o be_v &_o so_o of_o other_o also_o the_o denomination_n between_o
bc_o be_v to_o ca_n so_o be_v ca_n to_o cd_o the_o 1._o problem_n the_o 9_o proposition_n a_o right_a line_n be_v give_v to_o cut_v of_o from_o it_o any_o part_n appoint_v let_v the_o right_a line_n give_v be_v ab_fw-la it_o be_v require_v that_o from_o the_o same_o line_n ab_fw-la be_v cut_v of_o any_o part_n appoint_v suppose_v that_o a_o thyrd_o part_n be_v appoint_v to_o be_v cut_v of_o construction_n from_o the_o point_fw-fr a_o draw_v a_o right_a line_n ac_fw-la make_v with_o the_o line_n ab_fw-la a_o angle_n and_o in_o the_o line_n ac_fw-la take_v a_o point_n at_o all_o adventure_n which_o let_v be_v d._n and_o beginning_n at_o d_o put_v unto_o ad_fw-la two_o equal_a line_n de_fw-fr &_o ec_o by_o the_o 2._o of_o the_o first_o and_o draw_v a_o right_a line_n from_o b_o to_o c_z and_o by_o the_o point_n d_o by_o the_o ●1_n of_o the_o first_o draw_v unto_o bc_o a_o parallel_a line_n df._n demonstration_n now_o forasmuch_o as_o unto_o one_o of_o y_fw-fr side_n of_o the_o triangle_n abc_n namely_o unto_o the_o side_n bc_o be_v draw_v a_o parallel_a line_n fd_o it_o follow_v by_o the_o 2._o of_o this_o book_n that_o as_o cd_o be_v in_o proportion_n unto_o dam_n so_o be_v bf_o to_o fa._n but_o by_o construction_n cd_o be_v double_a to_o da._n wherefore_o y_fw-fr line_n bf_n be_v also_o double_a to_o the_o line_n fa._n wherefore_o the_o line_n basilius_n be_v treble_a unto_o the_o line_n af._n wherefore_o from_o the_o right_a line●_z give_v ab_fw-la be_v cut_v of_o a_o three_o part_n appoint_v namely_o of_o which_o be_v require_v to_o be_v do_v the_o 2._o problem_n the_o 10._o proposition_n to_o divide_v a_o right_a line_n give_v not_o divide_v like_a unto_o a_o right_a line_n give_v be_v divide_v svppose_v that_o the_o right_a line_n give_v not_o divide_v be_v ab_fw-la and_o the_o right_a line_n give_v be_v divide_v let_v be_v ac_fw-la it_o be_v require_v to_o divide_v the_o line_n ab_fw-la which_o be_v not_o divide_v like_o unto_o the_o line_n ac_fw-la which_o be_v divide_v construction_n suppose_v the_o line_n ac_fw-la be_v divide_v in_o the_o point_n d_o and_o e_o &_o let_v you_o line_n ab_fw-la &_o ac_fw-la so_o be_v put_v that_o they_o make_v a_o angle_n at_o all_o adventure_n and_o draw_v a_o line_n from_o b_o to_o c_z and_o by_o the_o point_n d_o and_o e_o draw_v unto_o the_o line_n bc_o by_o the_o 31._o of_o the_o first_o two_z parallel_v line_n df_o and_o eglantine_n and_o by_o the_o point_n d_o unto_o the_o line_n ab_fw-la by_o the_o same_o draw_v a_o parallel_n line_n dhk_n wherefore_o either_o of_o these_o figure●_n fh_o and_o hb_o be_v parallelogram_n wherefore_o the_o line_n dh_o be_v equal_a unto_o the_o line_n fg_o and_o the_o line_n hk_o be_v equal_a unto_o the_o line_n gb_o demonstration_n and_o because_o to_o one_o of_o the_o side_n of_o the_o triangle_n dkc_n namely_o to_o the_o side_n kc_o be_v draw_v a_o parallel_a line_n he_o therefore_o the_o line_n ce_fw-fr by_o th●_z 2._o of_o the_o six_o be_v in_o proportion_n unto_o the_o line_n ed_z as_o the_o line_n kh_o be_v to_o the_o line_n hd_v but_o the_o line_n kh_o be_v equal_a unto_o the_o line_n bg_o and_o the_o line_n hd_v be_v equal_a unto_o the_o line_n gf_o wherefore_o by_o the_o 11._o of_o the_o five_o as_o ce_fw-fr be_v unto_o ed_z so_o be_v bg_o to_o gf_o again_o because_o to_o one_o of_o the_o side_n of_o the_o triangle_n age_n namely_o to_o ge_z be_v draw_v a_o parallel_a line_n fd_o therefore_o the_o line_n ed_z by_o the_o 2._o of_o the_o six_o be_v in_o proportion_n unto_o the_o line_n dam_fw-ge as_o the_o line_n gf_o be_v to_o the_o line_n fa._n and_o it_o be_v already_o prove_v that_o as_o ce_fw-fr be_v to_o ed_z so_o be_v bg_o to_o gf_o wherefore_o as_o ce_fw-fr be_v to_o ed_z so_o be_v bg_o to_o gf_o and_o as_z ed_z be_v to_o da_z so_o be_v gf_o to_o fa._n wherefore_o the_o right_a line_n give_v not_o divide_v namely_o ab_fw-la be_v divide_v like_o unto_o the_o right_a line_n give_v be_v divide_v which_o be_v ac_fw-la which_o be_v require_v to_o be_v do_v ¶_o a_o corollary_n out_o of_o flussates_n flussates_n by_o this_o proposition_n we_o may_v divide_v any_o right_a line_n give_v accord_v to_o the_o proportion_n of_o any_o right_a line_n give_v for_o let_v those_o right_a line_n have_v proportion_n be_v join_v together_o direct_o that_o they_o may_v make_v all_o one_o right_a line_n and_o then_o join_v they_o to_o the_o line_n give_v anglewise_o and_o so_o proceed_v as_o in_o the_o proposition_n where_o you_o see_v that_o the_o right_a line_n give_v ab_fw-la be_v divide_v into_o the_o right_a line_n of_o fg_o and_o gb_o which_o have_v the_o self_n same_o proportion_n that_o the_o right_a line_n ad_fw-la de_fw-fr and_o ec_o have_v by_o this_o and_o the_o former_a proposition_n also_o may_v a_o right_a line_n give_v be_v easy_o divide_v into_o what_o part_n so_o ever_o you_o will_v name_v will._n as_o if_o you_o will_v divide_v the_o line_n ab_fw-la into_o three_o equal_a part_n let_v the_o line_n de_fw-fr be_v make_v equal_a to_o the_o line_n ad_fw-la and_o the_o line_n ec_o make_v equal_a to_o the_o same_o by_o the_o three_o of_o the_o first_o and_o then_o use_v the_o self_n same_o manner_n of_o construction_n that_o be_v before_o the_o line_n ab_fw-la shall_v be_v divide_v into_o three_o equal_a part_n and_o so_o of_o any_o kind_n of_o part_n whatsoever_o the_o 3._o problem_n the_o 11._o proposition_n unto_o two_o right_a line_n give_v to_o find_v a_o three_o in_o proportion_n with_o they_o svppose_v that_o there_o be_v two_o right_a line_n give_v basilius_n and_o ac_fw-la and_o let_v they_o be_v so_o put_v that_o they_o comprehend_v a_o angle_n howsoever_o it_o be_v it_o be_v require_v to_o find_v unto_o basilius_n and_o unto_o ac_fw-la a_o three_o line_n in_o proportion_n construction_n produce_v the_o line_n ab_fw-la and_o ac_fw-la unto_o the_o point_n d_o and_o e._n and_o unto_o the_o line_n ac_fw-la by_o the_o 2._o of_o the_o first_o put_v a_o equal_a line_n bd_o and_o draw_v a_o line_n from_o b_o to_o c._n and_o by_o the_o point_n d_o by_o the_o 31._o of_o the_o first_o draw_v unto_o the_o line_n bc_o a_o parallel_a line_n de_fw-fr which_o let_v concur_v with_o the_o line_n ac_fw-la in_o the_o point_n e._n demonstration_n now_o forasmuch_o as_o unto_o one_o of_o the_o side_n of_o the_o triangle_n ade_n namely_o to_o de_fw-fr be_v draw_v a_o parallel_a line_n bc_o therefore_o as_o ab_fw-la be_v in_o proportion_n unto_o bd_o so_o by_o the_o 2._o of_o the_o six_o be_v ac_fw-la unto_o ce._n but_o the_o line_n bd_o be_v equal_a unto_o the_o line_n ac_fw-la wherefore_o as_o the_o line_n ab_fw-la be_v to_o the_o line_n ac_fw-la so_o be_v the_o line_n ac_fw-la to_o the_o line_n ce._n wherefore_o unto_o the_o two_o right_a line_n give_v ab_fw-la and_o ac_fw-la be_v find_v a_o three_o line_n ce_fw-fr in_o proportion_n with_o they_o which_o be_v require_v to_o be_v do_v ¶_o a_o other_o way_n after_o pelitarius_n let_v the_o line_n ab_fw-la and_o bc_o be_v set_v direct_o in_o such_o sort_n that_o they_o both_o make_v one_o right_a line_n pelitarius_n then_o from_o the_o point_n a_o erect_v the_o line_n ad_fw-la make_v with_o the_o line_n ab_fw-la a_o angle_n at_o all_o adventure_n and_o put_v the_o line_n ad_fw-la equal_a to_o the_o line_n bc._n and_o draw_v a_o right_a line_n from_o d_z to_o b_o which_o produce_v beyond_o the_o point_n b_o unto_o the_o point_n e._n and_o by_o the_o point_n c_o draw_v unto_o the_o line_n da_z a_o parallel_a line_n ce_fw-fr concur_v with_o the_o line_n de_fw-fr in_o the_o point_n e._n then_o i_o say_v that_o the_o line_n ce_fw-fr be_v the_o three_o line_n proportional_a with_o the_o line_n ab_fw-la and_o bc._n for_o for●asmuch_o as_o by_o the_o 15._o of_o the_o first_o the_o angle_n b_o of_o the_o triangle_n abdella_n be_v equal_a to_o the_o angle_n b_o of_o the_o triangle_n cbe_n and_o by_o the_o 29._o of_o the_o same_o the_o angle_n a_o be_v equal_a to_o the_o angle_n c_o and_o the_o angle_n d_o to_o the_o angle_n e_o therefore_o by_o the_o 4._o of_o this_o book_n ab_fw-la be_v to_o dam_n as_o bc_o be_v to_o ce._n wherefore_o by_o the_o 11._o of_o the_o five_o ab_fw-la be_v to_o bc_o as_o bc_o be_v to_o ce_fw-fr which_o be_v require_v to_o be_v do_v ¶_o a_o other_o way_n also_o after_o pelitarius_n let_v the_o line_n ab_fw-la and_o bc_o be_v so_o join_v together_o pelitarius_n that_o they_o may_v make_v a_o right_a angle_n namely_o abc_n and_o draw_v a_o line_n from_o a_o to_o c_o and_o from_o the_o point_n c_o draw_v unto_o the_o line_n ac_fw-la a_o perpendicular_a cd_o by_o the_o 11._o of_o the_o first_o and_o
it_o a_o number_n equal_o equal_a equal_o because_o it_o be_v produce_v of_o the_o multiplication_n of_o three_o equal_a number_n the_o one_o into_o the_o other_o which_o three_o number_n be_v say_v in_o the_o second_o definition_n wherein_o he_o speak_v more_o apply_v to_o geometry_n to_o contain_v the_o cube_fw-la number_n it_o be_v therefore_o call_v a_o cube_fw-la number_n number_n because_o be_v describe_v by_o his_o unity_n it_o represent_v the_o form_n of_o a_o cube_fw-la in_o geometry_n who_o side_n that_o be_v to_o say_v who_o length_n breadth_n and_o thickness_n be_v the_o three_o equal_a number_n 9_o 9_z and_o 9_z of_o which_o he_o be_v produce_v which_o three_o side_n also_o be_v say_v to_o contain_v the_o cube_fw-la number_n 729_o behold_v here_o the_o description_n thereof_o definition_n 21_o number_n proportional_a be_v when_o the_o first_o be_v to_o the_o second_o equemultiplex_n as_o the_o three_o be_v to_o the_o four_o or_o the_o self_n same_o part_n or_o the_o self_n same_o part_n here_o he_o define_v which_o number_n be_v call_v proportional_a that_o be_v what_o number_n have_v one_o and_o the_o self_n same_o proportion_n for_o example_n 6._o to_o 3_o and_o 4._o to_o 2_o be_v number_n proportional_a and_o have_v one_o and_o th●_z self_n same_o proportion_n for_o 6._o the_o first_o be_v to_o 3._o the_o second_o equemultiplex_n as_o 4._o the_o three_o be_v to_o 2._o the_o four_o ●_o be_v double_a to_o 3_o and_o so_o be_v 4._o double_a to_o 2._o likewise_o these_o four_o number_n be_v in_o like_a proportion_n 3_o 9.4.1●_n for_o what_o part_n 3._o be_v of_o 9_o such_o part_n be_v 4._o of_o 12_o ●3_o of_o 9_o be_v a_o three_o part_n so_o be_v also_o 4._o of_o 12._o a_o three_o part_n so_o be_v these_o four_o number_n also_o in_o proportion_n ●_o 5_o 4._o 10_o what_o part_n 2._o be_v of_o 5_o such_o part_n be_v 4._o of_o 10_o 2_o of_o 5_o be_v two_o ●ift_a part_n likewise_o 4._o of_o 10_o be_v two_o five_o part_n moreover_o these_o number_n 8.6_o 1●_o 9_o be_v in_o proportion_n for_o what_o and_o how_o many_o part_n 8._o be_v of_o 6_o such_o &_o so_o many_o part_n be_v 12._o of_o 9_o 8._o of_o 6_o be_v four_o three_o part_n for_o one_o three_o part_n of_o 6._o be_v 2_o which_o take_v four_o time_n make_v 8_o so_o 12._o of_o 9_o be_v also_o four_o thyrd_o part_n for_o one_o three_o part_n of_o 9_o be_v 3_o which_o take_v four_o time_n make_v 1●_o and_o so_o conceive_v you_o of_o all_o other_o proportional_a number_n in_o the_o 〈◊〉_d definition_n of_o the_o v_o book_n euclid_n give_v a_o ●arre_n other_o definition_n of_o magnitude_n proportional_a and_o much_o unlike_a to_o this_o which_o he_o here_o give_v of_o number_n proportional_a number_n the_o reason_n be_v as_o there_o also_o be_v partly_o note_v for_o that_o there_o he_o give_v a_o definition_n common_a to_o all_o quantity_n discrete_a and_o continual_a rational_a and_o irrational_a and_o therefore_o be_v constrain_v to_o geve_v the_o definition_n by_o the_o excess_n equality_n or_o want_n of_o their_o equemultiplices_fw-la and_o that_o general_o only_a for_o that_o irrational_a quantity_n have_v no_o certain_a part_n or_o common_a measure_n to_o be_v measure_v by_o or_o know_v neither_o can_v they_o be_v express_v by_o any_o certain_a number_n but_o here_o in_o this_o place_n because_o in_o number_n there_o be_v no_o irrational_a quantity_n but_o all_o be_v certain_o know_v so_o that_o both_o they_o and_o the_o proportion_n between_o they_o may_v be_v express_v by_o number_n certain_a and_o know_v by_o reason_n of_o their_o part_n certain_a and_o for_o that_o they_o have_v some_o common_a measure_n to_o measure_v they_o at_o the_o least_o unity_n which_o be_v a_o common_a measure_n to_o all_o number_n he_o give_v here_o this_o definition_n of_o proportional_a number_n by_o that_o the_o one_o be_v like_o equemultiplex_n to_o the_o other_o or_o the_o same_o part_n or_o the_o same_o part_n which_o definition_n be_v much_o easy_a than_o be_v the_o other_o and_o be_v not_o so_o large_a as_o be_v the_o other_o neither_o extend_v itself_o general_o to_o all_o kind_n of_o quantity_n rational_a and_o irrational_a but_o contain_v itself_o within_o the_o limit_n and_o bond_n of_o rational_a quantity_n and_o number_n 22_o like_o plain_a number_n and_o like_o solid_a number_n be_v such_o definition_n which_o have_v their_o side_n proportional_a before_o he_o show_v that_o a_o plain_a number_n have_v two_o side_n and_o a_o solid_a number_n three_o side_n now_o he_o show_v by_o this_o definition_n which_o plain_a number_n and_o which_o solid_a number_n be_v like_o the_o one_o to_o the_o other_o the_o likeness_n of_o which_o number_n depend_v altogether_o of_o the_o proportion_n of_o the_o side_n of_o these_o number_n so_o that_o if_o the_o two_o side_n of_o one_o plain_a number_n have_v the_o same_o proportion_n the_o one_o to_o the_o other_o that_o the_o two_o side_n of_o the_o other_o plain_a number_n have_v the_o one_o to_o the_o other_o then_o be_v such_o two_o plain_a number_n like_o for_o a_o example_n 6_o and_o 24_o be_v two_o plain_a number_n the_o side_n of_o 6_o be_v 2_o and_o 3_o two_o time_n 3_o make_v 6_o the_o side_n of_o 24_o be_v 4_o and_o 6_o four_o time_n 6_o make_v 24._o again_o the_o same_o proportion_n that_o be_v between_o 3_o and_o 2_o the_o side_n of_o 6._o be_v also_o between_o 6_o and_o 4_o the_o side_n of_o 24._o wherefore_o 24_o and_o 6_o be_v two_o like_o plain_a and_o superficial_a number_n and_o so_o of_o other_o plain_a number_n after_o the_o same_o manner_n be_v it_o in_o solid_a number_n if_o three_o side_n of_o the_o one_o be_v in_o like_a proportion_n together_o as_o be_v the_o three_o side_n of_o the_o other_o then_o be_v the_o one_o solid_a number_n like_o to_o the_o other_o as_o 24_o and_o 192_o be_v solid_a number_n the_o side_n of_o 24._o be_v 2._o 3._o and_o 4_o two_o time_n there_o take_v 4_o time_n be_v 24._o the_o side_n of_o 192_o be_v 4.6_o and_o 8_o for_o four_o time_n 6._o 8_o time_n make_v 192._o again_o the_o proportion_n of_o 4_o to_o 3_o be_v sesquitercia_fw-la the_o proportion_n of_o 3_o to_o 2_o be_v sesquialtera_fw-la which_o be_v the_o proportion_n of_o the_o side_n of_o the_o one_o solid_a number_n namely_o of_o 24_o the_o proportion_n between_o 8_o and_o 6_o be_v sesqu●●ercia_n the_o proportion_n between_o 6_o and_o 4_o be_v sesquialtera_fw-la which_o be_v the_o proportion_n of_o the_o side_n of_o the_o other_o solid_a number_n namely_o of_o 191._o and_o they_o be_v one_o and_o the_o same_o with_o the_o proportione_n of_o the_o 〈◊〉_d of_o the_o other_o wherefore_o th●se_a two_z solid_a number_n 24_o and_o 192_o be_v like_a and_o so_o of_o other_o solid_a number_n 23_o a_o perfect_a number_n be_v that_o which_o be_v equal_a to_o all_o his_o part_n definition_n as_o the_o part_n of_o 6_o be_v 1._o 2._o 3._o three_o be_v the_o half_a of_o 6_o two_o the_o three_o part_n and_o 1._o the_o six_o part_n and_o more_o port_n 6_o have_v not_o which_o thr●●_n payte_v 1._o ●_o 3_o add_v together_o make_v 6_o the_o whole_a number_n who_o part_n they_o be_v wherefore_o 6_o be_v a_o perfect_a number_n so_o likewise_o be_v 28_o a_o perfect_a number_n the_o part_n whereof_o be_v these_o number_n 14._o 7._o 2._o and_o 1_o 14_o be_v the_o half_a thereof_o 7_o be_v the_o quarter_n 4_o be_v the_o seven_o part_n 2_o be_v a_o fourteen_o part_n and_o 1_o a_o 28_o part_n and_o these_o be_v all_o the_o part_n of_o 28._o all_o which_o namely_o 1_o 2_o 3_o 4_o 7_o and_o 14_o add_v together_o make_v just_o without_o more_o or_o l●sse_v 28._o wherefore_o 〈…〉_o a_o perfect_a number_n and_o so_o of_o other_o the_o like_a this_o kind_n of_o number_n be_v very_o rare_a and_o seldom_o find_v philosophy_n from_o 1_o to_o 10_o there_o be_v but_o one_o perfect_a number_n namely_o 6._o from_o 10_o to_o a_o 100_o there_o be_v also_o but_o one_o that_o be_v 28._o also_o from_o 100_o to_o 1000_o there_o be_v but_o one_o which_o be_v 496._o from_o 1000_o to_o 10000_o likewise_o but_o one_o so_o that_o between_o every_o s●ay_n in_o number_v which_o be_v ever_o in_o the_o ten_o place_n there_o be_v find_v but_o one_o perfect_a number_n and_o for_o their_o rareness_n and_o great_a perfection_n they_o be_v of_o marvellous_a use_n in_o magic_a and_o in_o the_o secret_a part_n of_o philosophy_n this_o kind_n of_o number_n be_v call_v perfect_a perfect_a in_o respect_n 〈…〉_o number_n which_o be_v imperfect_a for_o as_o the_o nature_n of_o a_o perfect_a number_n stand_v in_o this_o that_o all_o part_n add_v together_o be_v equal_a to_o the_o whole_a and_o make_v the_o whole_a so_o in_o a_o imperfect_a number_n all_o
measure_v b_o by_o the_o unity_n which_o be_v in_o b._n wherefore_o unity_n e_o so_o many_o time_n measure_v the_o number_n b_o as_o a_o measure_v d._n but_o unity_n e_o so_fw-mi many_o time_n measure_v the_o number_n b_o as_o a_o measure_v c._n wherefore_o a_o measure_v either_o of_o these_o number_n c_o and_o d_o a_o like_a wherefore_o by_o the_o 3._o common_a sentence_n of_o this_o book_n c_z be_v equal_a unto_o d_o which_o be_v require_v to_o be_v demonstrate_v the_o 15._o theorem_a the_o 17._o proposition_n if_o one_o number_n multiply_v two_o number_n and_o produce_v other_o number_n the_o number_n produce_v of_o they_o shall_v be_v in_o the_o self_n same_o proportion_n that_o the_o number_n multiply_v be_v svppose_v that_o the_o number_n a_o multiply_v two_o number_n b_o and_o c_o do_v produce_v the_o number_n d_o and_o e._n then_o i_o say_v that_o as_z b_o be_v to_o c_o so_o be_v d_z to_o e._n take_v unity_n namely_o f._n and_o forasmuch_o as_o a_o multiply_v b_o produce_v d_z therefore_o b_o measure_v d_z by_o those_o unity_n that_o be_v in_o a._n and_o unity_n fletcher_n measure_v a_o by_o th●s●_n u●iti●●_fw-fr whih_o be_v in_o a._n ●emonstra●ion_n wherefore_o unity_n fletcher_n so_o many_o time_n measure_v the_o number_n a_o as_z b_o measure_v d._n wherefore_o as_o unity_n i_o be_v to_o the_o number_n a._n so_o be_v the_o number_n b_o to_o the_o number_n d_o by_o the_o 21_o definition_n of_o this_o book_n and_o by_o the_o same_o reason_n as_o unity_n fletcher_n be_v to_o the_o number_n a_o so_o be_v the_o number_n c_o to_o the_o number_n e_o wherefore_o also_o by_o the_o 7._o common_a sentence_n of_o this_o book_n as_o b_o be_v to_o d_z so_o be_v c_o to_o e._n wherefore_o alternate_o by_o the_o 15._o of_o the_o seven_o as_o b_o be_v to_o c_o so_o be_v d_z to_o e._n if_o therefore_o one_o number_n multiply_v two_o numbers●_n and_o produce_v other_o number_n the_o number_n produce_v of_o they_o shall_v be_v in_o the_o self_n same_o proportion_n that_o the_o number_n multiply_v be_v which_o be_v require_v to_o be_v prove_v here_o flu●●tes_n add_v thi●_z corollary_n if_o two_o number●_n have_v one_o and_o the_o sam●_n proportion_n with_o two_o other_o number_n do_v multiply_v th●_z o●e_v the_o other_o alternate_o fluss●tes_n and_o produce_v any_o number_n the_o number_n produce_v of_o they_o shall_v be_v equal_a the_o one_o to_o the_o other_o suppose_v that_o there_o be_v two_o number●_n ●_o and_o b_o and_o also_o two_o other_o number_n c_o and_o d_o have_v th●_z same_o proportion_n that_o the_o number_n a_o and_o b_o have_v and_o let_v the_o number_n a_o and_o b_o multiply_v the_o number●_n c_o &_o d_o alternate_o that_o be_v let_v a_o multiply_v d_o produce_v f_o and_o let_v b_o multiply_v c_o produce_v e._n then_o i_o say_v that_o the_o number_n produce_v namely_o e_o &_o f_o be_v equal_a let_v a_o and_o b_o multiply_v the_o one_o the_o other_o in_o such_o sort_n that_o let_v a_o multiply_v b_o produce_v g_o and_o let_v b_o multiply_v a_o produce_v h_o now_o then_o the_o number_n g_o and_o h_o be_v equal_a by_o the_o 16._o of_o this_o booke●_n and_o forasmuch_o as_o a_o multipli●ng_a the_o two_o number_n b_o and_o d_z produce_v the_o number_n g_o and_o f_o therefore_o g_z be_v to_o ●_o as_z b_o be_v to_o d_z by_o this_o proposition_n so_o likewise_o b_o multiply_v the_o two_o number_n a_o and_o c_o produce_v the_o two_o number_n h_o and_o e._n wherefore_o by_o the_o same_o h_o be_v to_o e_o as_o a_o be_v to_o c._n but_o alternate_o by_o the_o 13._o of_o this_o book_n a_o be_v to_o c_o as_z b_o be_v to_o d_z but_o as_o a_o be_v to_o c_o so_o be_v h_z to_o e_o and_o as_z ●_o be_v to_o d_z so_o be_v g_z to_o ●_o wherefore_o by_o the_o seven_o common_a sentence_n as_o h_o be_v to_o e●_n ●_z so_o be_v g_z to_o f._n wherefore_o alternate_o by_o the_o 13._o of_o this_o book_n h_o be_v to_o g_z as_z e_o be_v to_o f._n but_o it_o be_v prove_v that_o g_z &_o h_o be_v equal_a wherefore_o e_o and_o fletcher_n which_o have_v the_o same_o proportion_n that_o a_o and_o b_o have_v be_v equal_a if_o therefore_o there_o be_v two_o number_n etc_n etc_n which_o be_v require_v to_o be_v prove_v ¶_o the_o 16._o theorem_a the_o 18._o proposition_n if_o two_o number_n multiply_v any_o number_n &_o produce_v other_o number_n the_o number_n of_o they_o produce_v shall_v be_v in_o the_o same_o proportion_n that_o the_o number_n multiply_v be_v svppose_v that_o two_o number_n a_o and_o b_o multiply_v the_o number_n c_o do_v produce_v the_o number_n d_o and_o e._n demonstration_n then_o i_o say_v that_o as_o a_o be_v to_o b_o so_o be_v d_z to_o e._n for_o forasmuch_o as_o a_o multiply_v c_o produce_v d_z therefore_o c_o multiply_v a_o produce_v also_o d_z by_o the_o 16._o of_o this_o book_n and_o by_o the_o same_o reason_n c_o multiply_v b_o produce_v e._n now_o then_o one_o number_n c_z multiply_v two_o number_n a_o and_o b_o produce_v the_o number_n d_z and_o e._n wherefore_o by_o the_o 17._o of_o the_o seven_o as_o a_o be_v to_o b_o so_o be_v d_z to_o e_o which_o be_v require_v to_o be_v demonstrate_v this_o proposition_n and_o the_o former_a touch_v two_o number_n may_v be_v extend_v to_o number_n how_o many_o soever_o soever_o so_o that_o if_o one_o number_n multiply_v number_n how_o many_o soever_o and_o produce_v any_o number_n the_o proportion_n of_o the_o number_n produce_v and_o of_o the_o number_n multiply_v shall_v be_v one_o and_o the_o self_n same_o likewise_o if_o number_n how_o many_o soever_o multiply_v one_o number_n and_o produce_v any_o number_n the_o proportion_n of_o the_o number_n produced●_n and_o of_o the_o number_n multiply_v shall_v be_v one_o and_o the_o self_n same_o which_o thing_n by_o this_o and_o the_o former_a proposition_n repeat_v as_o often_o as_o be_v needful_a be_v not_o hard_a to_o prove_v ¶_o the_o 17._o theorem_a the_o 19_o proposition_n if_o there_o be_v four_o number_n in_o proportion_n the_o number_n produce_v of_o the_o first_o and_o the_o four_o be_v equal_a to_o that_o number_n which_o be_v produce_v of_o the_o second_o and_o the_o three_o and_o if_o the_o number_n which_o be_v produce_v of_o the_o first_o and_o the_o four_o be_v equal_a to_o that_o which_o be_v produce_v of_o the_o second_o &_o the_o three_o those_o four_o number_n shall_v be_v in_o proportion_n but_o now_o again_o suppose_v that_o e_o be_v equal_a unto_o f._n then_o i_o say_v that_o as_o a_o be_v to_o b_o so_o be_v c_o to_o d._n first_o for_o the_o same_o order_n of_o construction_n remain_v still_o forasmuch_o as_o a_o multiply_v c_o &_o d_o produce_v g_z and_o e_o therefore_o by_o the_o 17._o of_o the_o seven_o as_o c_o be_v to_o d_z so_o be_v g_z to_o e_o but_o e_o be_v equal_a unto_o fletcher_n but_o if_o two_o number_n be_v equal_a one_o number_n shall_v have_v unto_o they_o on●_n and_o the_o same_o proportion_n wherefore_o as_o g_z be_v to_o e_o so_o be_v g_z to_o f._n but_o as_o g_z be_v to_o e_o so_o be_v c_o to_o d._n wherefore_o as_o c_o be_v to_o d_z so_o be_v g_z to_o fletcher_n but_o as_o g_z be_v to_o fletcher_n so_o be_v a_o to_o b_o by_o the_o 18._o of_o the_o seven_o wherefore_o as_o a_o be_v to_o b_o so_o be_v c_z to_o d_z demonstration_n which_o be_v require_v to_o be_v prove_v campane_n here_o campane_n add_v that_o it_o be_v needless_a to_o demonstrate_v that_o if_o one_o number_n have_v to_o two_o number_n one_o and_o the_o same_o proportion_n the_o say_v two_o number_n shall_v be_v equal_a or_o that_o if_o they_o be_v equal_a one_o number_n have_v to_o they_o one_o and_o the_o same_o proportion_n for_o say_v he_o if_o g_o have_v unto_o e_o and_o f_o one_o and_o the_o same_o proportion_n they_o either_o what_o part_n or_o part_n g_z be_v to_o e_o the_o same_o part_n or_o part_n be_v g_z also_o of_o fletcher_n or_o how_o multiplex_n g_z be_v to_o e_o so_o multiplex_n be_v g_z to_o fletcher_n by_o the_o 21._o definition_n and_o therefore_o by_o the_o 2_o and_o 3_o common_a sentence_n the_o say_a number_n shall_v be_v equal_a and_o so_o converse_o if_o the_o two_o number_n e_o and_o f_o be_v equal_a then_o shall_v the_o number_n e_o and_o f_o be_v either_o the_o self_n same_o part_n or_o part_n of_o the_o number_n g_o or_o they_o shall_v be_v equemultiplices_fw-la unto_o it_o and_o therefore_o by_o the_o same_o definition_n the_o number_n g_o shall_v have_v to_o the_o number_n e_o and_o f_o one_o and_o the_o same_o proportion_n ¶_o the_o 18._o theorem_a the_o 20._o proposition_n if_o there_o be_v three_o number_n in_o proportion_n the_o number_n
wherefore_o a_o be_v a_o plain_a number_n and_o the_o side_n thereof_o be_v d_z and_o fletcher_n by_o the_o 17._o definition_n of_o the_o seven_o again_o forasmuch_o as_o d_z and_o e_o be_v the_o least_a number_n that_o have_v one_o &_o the_o same_o proportion_n with_o c_o b_o therefore_o by_o the_o 21._o of_o the_o seven_o how_o many_o time_n d_z measure_v c_o so_fw-mi many_o time_n do_v e_o measure_n b._n how_o often_o e_o measure_v b_o so_fw-mi many_o unity_n let_v there_o be_v in_o g._n wherefore_o e_o measure_v b_o by_o those_o unity_n which_o be_v in_o g_o wherefore_o g_z multiply_a e_o produce_v b_o wherefore_o b_o be_v a_o plain_a number_n by_o the_o 17._o definition_n of_o the_o seven_o demonstration_n and_o the_o side_n thereof_o be_v e_o and_o g._n wherefore_o those_o two_o number_n a_o and_o b_o be_v two_o plain_a number_n i_o say_v moreover_o that_o they_o be_v like_a for_o forasmuch_o as_o fletcher_n multiply_v e_o produce_v c_z and_o g_z multiply_v e_o produce_v b_o therefore_o by_o the_o 17._o of_o the_o seven_o as_o fletcher_n be_v to_o g_o so_o be_v c_z to_o b_o but_o as_z c_z be_v to_o b_o so_o be_v d_z to_o e_o wherefore_o as_o d_z be_v to_o e_o so_o be_v fletcher_n to_o g._n wherefore_o a_o and_o b_o be_v like_o plain_a number_n for_o their_o side_n be_v proportional_a which_o be_v require_v to_o be_v prove_v ¶_o the_o 19_o theorem_a the_o 21._o proposition_n if_o between_o two_o number_n there_o be_v two_o mean_v proportional_a number_n those_o number_n be_v like_o solid_a number_n proposition_n svppose_v that_o between_o two_o number_n a_o and_o b_o there_o be_v two_o mean_v proportional_a number_n c_o d._n then_o i_o say_v that_o a_o and_o b_o be_v like_o solid_a number_n take_v by_o the_o 3●_o of_o the_o seven_o or_o 2._o of_o the_o eight_o three_o of_o the_o least_o number_n that_o have_v one_o and_o the_o same_o proportion_n with_o a_o c_o d_o b_o and_o let_v the_o same_o be_v e_o f_o g._n wherefore_o by_o the_o 3._o of_o the_o eight_o their_o extreme_n e_o g_o be_v prime_a the_o one_o to_o the_o other_o and_o forasmuch_o as_o between_o the_o number_n e_o and_o g_o there_o be_v one_o mean_v proportional_a number_n construction_n therefore_o by_o the_o 20_o of_o the_o eight_o they_o be_v like_o plain_a number_n suppose_v that_o the_o side_n of_o e_o be_v h_o and_o k._n and_o let_v the_o side_n of_o g_o be_v l_o and_o m._n now_o it_o be_v manifest_a that_o these_o number_n e_o f_o g_o be_v in_o continual_a proportion_n demonstration_n and_o in_o the_o same_o proportion_n that_o h_o be_v to_o l_o and_o that_o king_n be_v to_o m._n and_o forasmuch_o a●_z e_o f_o g_o be_v the_o least_o number_n that_o have_v one_o and_o the_o same_o proportion_n with_o a_o c_o d_o therefore_o of_o equality_n by_o the_o 14._o of_o the_o seven_o as_o e_o be_v to_o g_z so_o be_v a_o to_o d._n but_o e_o g_o be_v by_o the_o 3._o of_o the_o eight_o prime_a number_n yea_o they_o be_v prime_a and_o the_o least_o but_o the_o least_o number_n by_o the_o 21._o of_o the_o seven_o measure_v those_o number_n that_o have_v one_o &_o the_o same_o proportion_n with_o they_o equal_o the_o great_a the_o great_a and_o the_o less_o the_o less_o that_o be_v the_o antecedent_n the_o antecedent_n &_o the_o consequent_a the_o consequent_a therefore_o how_o many_o time●_n e_o measure_v a_o so_o many_o time_n g_z measure_v d._n how_o many_o time_n e_o measure_v a_o so_o many_o unity_n let_v there_o be_v in_o n._n wherefore_o n_o multiply_v e_o produce_v a._n but_o e_o be_v produce_v of_o the_o number_n h_o k._n wherefore_o n_o multiply_v that_o which_o be_v produce_v of_o h_o edward_n produce_v a._n wherefore_o a_o be_v a_o solid_a number_n and_o the_o side_n thereof_o be_v h_o edward_n n._n again_o forasmuch_o as_o e_o f_o g_o be_v the_o least_o number_n that_o have_v one_o and_o the_o same_o proportion_n with_o c_o d_o b_o therefore_o how_o many_o time_n e_o measure_v c_o so_fw-mi many_o time_n g_z measure_v b._n how_o oftentimes_o g_z measure_v b_o so_fw-mi many_o unity_n let_v there_o be_v in_o x._o wherefore_o g_o measure_v b_o by_o those_o unity_n which_o be_v in_o x._o wherefore_o x_o multiply_v g_o produce_v b._n but_o g_o be_v produce_v of_o the_o number_n l_o m._n wherefore_o x_o multiply_v that_o number_n which_o be_v produce_v of_o l_o and_o m_o produce_v b._n wherefore_o b_o be_v a_o solid_a number_n and_o the_o side_n thereof_o be_v l_o m_o x._o wherefore_o a_o b_o be_v solid_a number_n i_o say_v moreover_o that_o they_o be_v like_o solid_a number_n for_o forasmuch_o as_o n_o and_o x_o multiply_v e_o produce_v a_o and_o c_o therefore_o by_o the_o 18._o of_o the_o seven_o as_o n_o be_v to_o x_o so_o i●_z a_o to_o c_o that_o be_v e_o ●o_z f._n but_o as_o e_o be_v to_o fletcher_n so_o be_v h_o to_o l_o and_o king_n to_o m_o therefore_o as_o h_o be_v to_o l_o so_o be_v king_n to_o m_o and_o n_o to_o x._o and_o h_o edward_n n_o be_v the_o side_n of_o a_o and_o likewise_o l_o m_o x_o a●●_n th●_z side_n of_o b●_n wherefore_o a_o b●_n be_v like_o solid_a number_n which_o be_v require_v to_o be_v prove_v ¶_o the_o 20._o theorem_a the_o 22._o proposition_n if_o three_o number_n be_v in_o continual_a proportion_n and_o if_o the_o first_o be_v a_o square_a number_n the_o three_o also_o shall_v be_v a_o square_a number_n svppose_v that_o there_o be_v three_o number_n in_o continual_a proportion_n a_o b_o c_o and_o let_v the_o first_o be_v a_o square_a number_n demonstration_n then_o i_o say_v that_o the_o three_o be_v also_o a_o square_a number_n for_o forasmuch_o as_o between_o a_o and_o c_o there_o be_v one_o mean_v proportional_a number●_n namely_o b_o therefore_o by_o the_o 20._o of_o the_o eight_o a_o and_o c_o be_v like_o plain_a number_n but_o a_o be_v a_o square_a number_n wherefore_o c_z also_o be_v a_o square_a number_n which_o be_v require_v to_o be_v prove_v ¶_o the_o 21._o theorem_a the_o 23._o proposition_n if_o four_o number_n be_v in_o continual_a proportion_n and_o if_o the_o first_o be_v a_o cube_fw-la number_n the_o four_o also_o shall_v be_v a_o cube_fw-la number_n svppose_v that_o there_o be_v four_o number_n in_o continual_a proportion_n a_o b_o c_o d._n demonstration_n and_o let_v a_o be_v a_o cube_fw-la number_n then_o i_o say_v that_o d_o also_o be_v a_o cube_fw-la number_n for_o forasmuch_o as_o between_o a_o and_o d_o there_o be_v two_o mean_v proportional_a number_n b●_n c._n therefore_o a_o d_o be_v like_o solid_a number_n by_o the_o 21._o of_o this_o book_n but_o a_o be_v a_o cube_fw-la number_n wherefore_o d_z also_o be_v a_o cube_fw-la number●_n which_o be_v require_v to_o be_v demonstrate_v ¶_o the_o 22._o theorem_a the_o 24._o proposition_n if_o two_o number_n be_v in_o the_o same_o proportion_n that_o a_o square_a number_n be_v to_o a_o square_a number_n and_o if_o the_o first_o be_v a_o square_a number_n the_o second_o also_o shall_v be_v a_o square_a number_n svppose_v that_o two_o number_n a_o and_o b_o be_v in_o the_o same_o proportion_n that_o the_o square_a number_n c_o be_v unto_o the_o squ●●●_n number_n d._n and_o let_v a_o be_v a_o square_a number_n demonstration_n then_o i_o say_v that_o b_o also_o be_v a_o square_a number_n for_o forasmuch_o as_o c_z and_o d_o be_v square_a number_n therefore_o g_z and_o d_o be_v like_o plain_a number_n wherefore_o by_o the_o 18._o of_o the_o eight_o between_o c_o and_o d_o there_o be_v one_o mean_v proportional_a number_n but_o as_o c_o be_v to_o d_z so_o be_v a_o to_o b._n wherefore_o between_o a_o and_o b_o there_o be_v one_o mean_v proportional_a number_n by_o the_o 8._o of_o the_o eight_o but_o a_o be_v a_o square_a number_n wherefore_o by_o the_o 22._o of_o the_o eight_o b_o also_o be_v a_o square_a number_n which_o be_v require_v to_o be_v prove_v ¶_o the_o 23._o theorem_a the_o 25._o proposition_n if_o two_o number_n be_v in_o the_o same_o proportion_n the_o one_o to_o the_o other_o that_o a_o cube_fw-la number_n be_v to_o a_o cube_fw-la number_n and_o if_o the_o first_o be_v a_o cube_fw-la number_n the_o second_o also_o shall_v be_v a_o cube_fw-la number_n svppose_v that_o two_o number_n a_o and_o b_o be_v in_o the_o same_o proportion_n the_o one_o to_o the_o other_o that_o the_o cube_fw-la number_n c_z be_v unto_o the_o cube_fw-la number_n d._n and_o let_v a_o be_v a_o cube_fw-la number_n then_o i_o say_v that_o b_o also_o be_v a_o cube_fw-la number_n for_o forasmuch_o as_o c_o d_o be_v cube_fw-la number_n therefore_o c_z demonstration_n d_o be_v like_o solid_a number_n wherefore_o by_o the_o 19_o of_o the_o eight_o between_o c_o and_o d_o
e_o produce_v d_z wherefore_o a_o measure_v d_z but_o it_o also_o measure_v it_o not_o which_o be_v impossible_a wherefore_o it_o be_v impossible_a to_o find_v out_o a_o four_o number_n proportional_a with_o these_o number_n a_o b_o c_o whensoever_o a_o measure_v not_o d._n ¶_o the_o 20._o theorem_a the_o 20._o proposition_n prime_n number_n be_v give_v how_o many_o soever_o there_o may_v be_v give_v more_o prime_a number_n svppose_v that_o the_o prime_a number_n give_v be_v a_o b_o c._n proposition_n then_o i_o say_v that_o there_o be_v yet_o more_o prime_a number_n beside_o a_o b_o c._n take_v by_o the_o 38._o of_o the_o seven_o the_o lest_o number_v who_o these_o number_n a_o b_o c_o do_v measure_n and_o let_v the_o same_o be_v de._n and_o unto_o de_fw-fr add_v unity_n df._n now_o of_o be_v either_o a_o prime_a number_n or_o not_o first_o let_v it_o be_v a_o prime_a number_n case_n then_o be_v there_o find_v these_o prime_a number_n a_o b_o c_o and_o of_o more_o in_o multitude_n then_o the_o prime_a number_n ●irst_n give_v a_o b_o c._n but_o now_o suppose_v that_o of_o be_v not_o prime_a case_n wherefore_o some_o prime_a number_n measure_v it_o by_o the_o 24._o of_o the_o seven_o let_v a_o prime_a number_n measure_v it_o namely_o g._n then_o i_o say_v that_z g_z be_v none_o of_o these_o number_n a_o b_o c._n for_o if_o g_z be_v one_o and_o the_o same_o with_o any_o of_o these_o a_o b_o c._n but_o a_o b_o c_o measure_v the_o number_n de_fw-fr wherefore_o g_z also_o measure_v de_fw-fr and_o it_o also_o measure_v the_o whole_a ef._n wherefore_o g_o be_v a_o number_n shall_v measure_v the_o residue_n df_o be_v unity_n which_o be_v impossible_a wherefore_o g_z be_v not_o one_o and_o the_o same_o with_o any_o of_o these_o prime_a number_n a_o b_o c_o and_o it_o be_v also_o suppose_a to_o be_v a_o prime_a number_n wherefore_o there_o be_v ●ound_v these_o prime_a number_n a_o b_o c_o g_o be_v more_o in_o multitude_n then_o the_o prime_a number_n give_v a_o b_o c_o which_o be_v require_v to_o be_v demonstrate_v a_o corollary_n by_o this_o proposition_n it_o be_v manifest_a that_o the_o multitude_n of_o prime_a number_n be_v infinite_a ¶_o the_o 21._o theorem_a the_o 21._o proposition_n if_o even_o number_n how_o many_o soever_o be_v add_v together_o the_o whole_a shall_v be_v even_o svppose_v that_o these_o even_a number_n ab_fw-la bc_o cd_o and_o de_fw-fr be_v add_v together_o then_o i_o say_v that_o the_o whole_a number_n namely_o ae_n be_v a_o even_a number_n demonstration_n for_o forasmuch_o as_o every_o one_o of_o these_o number_n ab_fw-la bc_o cd_o and_o de_fw-fr be_v a_o even_a number_n therefore_o every_o one_o of_o they_o have_v a_o half_a wherefore_o the_o whole_a ae_n also_o have_v a_o half_a but_o a_o even_a number_n by_o the_o definition_n be_v that_o which_o may_v be_v divide_v into_o two_o equal_a part_n wherefore_o ae_n be_v a_o even_a number_n which_o be_v require_v to_o be_v prove_v ¶_o the_o 22._o theorem_a the_o 22._o proposition_n if_o odd_a number_n how_o many_o soever_o be_v add_v together_o &_o if_o their_o multitude_n be_v even_o the_o whole_a also_o shall_v be_v even_o svppose_v that_o these_o odd_a number_n ab_fw-la bc_o cd_o and_o de_fw-fr be_v even_o in_o multitude_n be_v add_v together_o then_o i_o say_v that_o the_o whole_a ae_n be_v a_o even_a number_n for_o forasmuch_o as_o every_o one_o of_o these_o number_n ab_fw-la bc_o cd_o and_o de_fw-fr be_v a_o odd_a number_n be_v you_o take_v away_o unity_n from_o every_o one_o of_o they_o demonstration_n that_o which_o remain_v o●_n every_o one_o of_o they_o be_v a_o even_a number_n wherefore_o they_o all_o add_v together_o be_v by_o the_o 21._o of_o the_o nine_o a_o even_a number_n and_o the_o multitude_n of_o the_o unity_n take_v away_o be_v even_o wherefore_o the_o whole_a ae_n be_v a_o even_a number_n which_o be_v require_v to_o be_v prove_v ¶_o the_o 23._o theorem_a the_o 23._o proposition_n if_o odd_a number_n how_o many_o soever_o be_v add_v together_o and_o if_o the_o multitude_n of_o they_o be_v odd_a the_o whole_a also_o shall_v be_v odd_a svppose_v that_o these_o odd_a number_n ab_fw-la bc_o and_o cd_o be_v odd_a in_o multitude_n be_v add_v together_o then_o i_o say_v that_o the_o whole_a ad_fw-la be_v a_o odd_a number_n take_v away_o from_o cd_o unity_n de_fw-fr wherefore_o that_o which_o remain_v ce_fw-fr be_v a_o even_a number_n but_o ac_fw-la also_o by_o the_o 22._o of_o the_o nine_o be_v a_o even_a number_n demonstration_n wherefore_o the_o whole_a ae_n be_v a_o even_a number_n but_o de_fw-fr which_o be_v unity_n be_v add_v to_o the_o even_a number_n ae_n make_v the_o whole_a ad_fw-la a●_z odd_a number_n which_o be_v require_v to_o be_v proved●_n ¶_o the_o 24._o theorem_a the_o 24._o proposition_n if_o from_o a_o even_a number_n be_v take_v away_o a_o even_a number_n that_o which_o remain_v shall_v be_v a_o even_a number_n svppose_v that_o ab_fw-la be_v a_o even_a number_n and_o from_o it_o take_v away_o a_o even_a number_n cb._n demonstration_n then_o i_o say_v that_o that_o which_o remain_v namely_o ac_fw-la be_v a_o even_a number_n for_o forasmuch_o as_o ab_fw-la be_v a_o even_o even_a number_n it_o have_v a_o half_a and_o by_o the_o same_o reason_n also_o bc_o have_v a_o half_a wherefore_o the_o residue_n ca_n have_v a_o half_a wherefore_o ac_fw-la be_v a_o even_a number_n which_o be_v require_v to_o be_v demonstrate_v ¶_o the_o 25._o theorem_a the_o 25._o proposition_n if_o from_o a_o even_a number_n be_v take_v away_o a_o odd_a number_n that_o which_o remain_v shall_v be_v a_o odd_a number_n svppose_v that_o ab_fw-la be_v a_o even_a number_n and_o take_v away_o from_o it_o bc_o a_o odd_a number_n then_o i_o say_v that_o the_o residue_n ca_n be_v a_o odd_a number_n demonstration_n take_v away_o from_o bc_o unity_n cd_o wherefore_o db_o be_v a_o even_a number_n and_o ab_fw-la also_o be_v a_o even_a number_n wherefore_o the_o residue_n ad_fw-la be_v a_o even_a number_n by_o the_o ●ormer_a proposition_n but_o cd_o which_o be_v unity_n be_v take_v away_o from_o the_o even_a number_n ad_fw-la make_v the_o residue_n ac_fw-la a_o odd_a number_n which_o be_v require_v to_o be_v prove_v ¶_o the_o 26._o theorem_a the_o 26._o proposition_n if_o from_o a_o odd_a number_n be_v take_v away_o a_o odd_a number_n that_o which_o remain_v shall_v be_v a_o even_a number_n svppose_v that_o ab_fw-la be_v a_o odd_a number_n and_o from_o it_o take_v away_o a_o odd_a number_n bc._n then_o i_o say_v that_o the_o residue_n ca_n be_v a_o even_a number_n demonstration_n for_o forasmuch_o as_o ab_fw-la be_v a_o odd_a number_n take_v away_o from_o it_o unity_n bd._n wherefore_o the_o residue_n ad_fw-la be_v even_o and_o by_o the_o same_o reason_n cd_o be_v a_o even_a number_n wherefore_o the_o residue_n ca_n be_v a_o even_a number_n by_o the_o 24._o of_o this_o book_n ●_o which_o be_v require_v to_o be_v prove_v ¶_o the_o 27._o theorem_a the_o 27._o proposition_n if_o from_o a_o odd_a number_n be_v take_v a_o way_n a_o even_a number_n the_o residue_n shall_v be_v a_o odd_a number_n svppose_v that_o ab_fw-la be_v a_o odd_a number_n and_o from_o it_o take_v away_o a_o even_a number_n bc._n demonstration_n then_o i_o say_v that_o the_o residue_n ca_n be_v a_o odd_a number_n take_v away_o from_o ab_fw-la unity_n ad._n wherefore_o the_o residue_n db_o be_v a_o even_a number_n &_o bc_o be_v by_o supposition_n even_o wherefore_o the_o residue_n cd_o be_v a_o even_a number_n wherefore_o dam_n which_o be_v unity_n be_v add_v unto_o cd_o which_o be_v a_o even_a number_n make_v the_o whole_a ac_fw-la a_o ●dde_a number_n which_o be_v require_v to_o be_v prove_v ¶_o the_o 28._o theorem_a the_o 28._o proposition_n if_o a_o odd_a number_n multiply_v a_o even_a number_n produce_v any_o number_n the_o number_n produce_v shall_v be_v a_o even_a number_n svppose_v that_o a_o be_v a_o odd_a number_n multiply_v b_o be_v a_o even_a number_n do_v produce_v the_o number_n c._n then_o i_o say_v that_o c_z be_v a_o even_a number_n demonstration_n for_o forasmuch_o as_o a_o multiply_v b_o produce_v c_z therefore_o c_z be_v compose_v of_o so_o many_o number_n equal_a unto_o b_o as_o there_o be_v in_o unity_n in_o a._n but_o b_o be_v a_o even_a number_n wherefore_o c_o be_v compose_v of_o so_o many_o even_a number_n as_o there_o be_v unity_n in_o a._n but_o if_o even_a number_n how_o many_o soever_o be_v add_v together_o the_o whole_a by_o the_o 21._o of_o the_o nine_o be_v a_o even_a number_n wherefore_o c_o be_v a_o even_a number_n which_o be_v require_v to_o be_v demonstrate_v ¶_o the_o 29._o theorem_a the_o 29._o proposition_n i●_z a_o odd_a number_n multiply_v a_o
number_n be_v make_v of_o unity_n and_o therefore_o can_v a_o point_n be_v a_o common_a part_n of_o all_o line_n and_o measure_v they_o as_o unity_n be_v a_o common_a part_n of_o all_o number_n and_o measure_v they_o unity_n take_v certain_a time_n make_v any_o number_n for_o there_o be_v not_o in_o any_o number_n infinite_a unity_n but_o a_o point_n take_v certain_a time_n yea_o as_o often_o as_o you_o listen_v never_o make_v any_o line_n for_o that_o in_o every_o line_n there_o be_v infinite_a point_n wherefore_o line_n figure_n and_o body_n in_o geometry_n be_v oftentimes_o incommensurable_a and_o irrational_a now_o which_o be_v rational_a and_o which_o irrational_a which_o commensurable_a and_o which_o incommensurable_a how_o many_o and_o how_o sundry_a sort_n and_o kind_n there_o be_v of_o they_o what_o be_v their_o nature_n passion_n and_o property_n do_v euclid_n most_o manifest_o show_v in_o this_o book_n and_o demonstrate_v they_o most_o exact_o this_o ten_o book_n have_v ever_o hitherto_o of_o all_o man_n and_o be_v yet_o think_v &_o account_v to_o be_v the_o hard_a book_n to_o understand_v of_o all_o the_o book_n of_o euclid_n euclid_n which_o common_a receive_a opinion_n have_v cause_v many_o to_o shrink_v and_o have_v as_o it_o be_v deter_v they_o from_o the_o handle_n and_o treaty_n thereof_o there_o have_v be_v in_o deed_n in_o time_n past_a and_o be_v present_o in_o these_o our_o day_n many_o which_o have_v deal_v and_o have_v take_v great_a and_o good_a diligence_n in_o comment_v amend_v and_o restore_a of_o the_o six_o first_o book_n of_o euclid_n and_o there_o have_v stay_v themselves_o and_o go_v no_o far_o be_v deter_v and_o make_v afraid_a as_o it_o seem_v by_o the_o opinion_n of_o the_o hardness_n of_o this_o book_n to_o pass_v forth_o to_o the_o book_n follow_v truth_n it_o be_v that_o this_o book_n have_v in_o it_o somewhat_o a_o other_o &_o strange_a manner_n of_o matter_n entreat_v of_o former_a them_z the_o other_o book_n before_o have_v and_o the_o demonstration_n also_o thereof_o &_o the_o order_n seem_v likewise_o at_o the_o first_o somewhat_o strange_a and_o unaccustomed_a which_o thing_n may_v seem_v also_o to_o cause_v the_o obscurity_n thereof_o and_o to_o fear_v away_o many_o from_o the_o read_n and_o diligent_a study_n of_o the_o same_o so_o much_o that_o many_o of_o the_o well_o learned_a have_v much_o complain_v of_o the_o darkness_n and_o difficulty_n thereof_o and_o have_v think_v it_o a_o very_a hard_a thing_n and_o in_o manner_n impossible_a to_o attain_v to_o the_o right_n and_o full_a understanding_n of_o this_o book_n algebra_n without_o the_o aid_n and_o help_v of_o some_o other_o knowledge_n and_o learning_n and_o chief_o without_o the_o knowledge_n of_o that_o more_o secret_a and_o subtle_a part_n of_o arithmetic_n common_o call_v algebra_n which_o undoubted_o first_o well_o have_v and_o know_v will_v geve_v great_a light_n thereunto_o yet_o certain_o may_v this_o book_n very_o well_o be_v enter_v into_o and_o full_o understand_v without_o any_o strange_a help_n or_o succour_n only_o by_o diligent_a observation_n of_o the_o order_n and_o course_n of_o euclides_n write_n so_o that_o he_o which_o diligent_o have_v peruse_v and_o full_o understand_v the_o 9_o book_n go_v before_o and_o mark_v also_o earnest_o the_o principle_n and_o definition_n of_o this_o ●enth_fw-mi book_n he_o shall_v well_o perceive_v that_o euclid_n be_v of_o himself_o a_o sufficient_a teacher_n and_o instructor_n understand_v and_o need_v not_o the_o help_n of_o any_o other_o and_o shall_v soon_o see_v that_o this_o ten_o book_n be_v not_o of_o such_o hardness_n and_o obscurity_n as_o it_o have_v be_v hitherto_o think_v yea_o i_o doubt_v not_o but_o that_o by_o the_o travel_n and_o industry_n take_v in_o this_o translation_n and_o by_o addition_n and_o emendation_n get_v of_o other_o there_o shall_v appear_v in_o it_o no_o hardness_n at_o all_o but_o shall_v be_v as_o easy_a as_o the_o rest_n of_o his_o book_n be_v definition_n definition_n 1_o magnitude_n commensurable_a be_v suchwhich_v one_o and_o the_o self_n same_o measure_n do_v measure_n first_o he_o show_v what_o magnitude_n be_v commensurable_a one_o to_o a_o other_o to_o the_o better_a and_o more_o clear_a understanding_n of_o this_o definition_n note_v that_o that_o measure_v whereby_o any_o magnitude_n be_v measure_v be_v less_o than_o the_o magnitude_n which_o it_o measure_v or_o at_o least_o equal_a unto_o it_o for_o the_o great_a can_v by_o no_o mean_n measure_v the_o less_o far_o it_o behove_v that_o that_o measure_n if_o it_o be_v equal_a to_o that_o which_o be_v measure_v take_v once_o make_v the_o magnitude_n which_o be_v measure_v if_o it_o be_v less_o than_o oftentimes_o take_v and_o repeat_v it_o must_v precise_o render_v and_o make_v the_o magnitude_n which_o it_o measure_v which_o thing_n in_o number_n be_v easy_o see_v for_o that_o as_o be_v before_o say_v all_o number_n be_v commensurable_a one_o to_o a_o other_o and_o although_o euclid_n in_o this_o definition_n comprehend_v purpose_o only_o magnitude_n which_o be_v continual_a quantity_n as_o be_v line_n superficiece_n and_o body_n yet_o undoubted_o the_o explication_n of_o this_o and_o such_o like_a place_n be_v apt_o to_o be_v seek_v of_o number_n as_o well_o rational_a as_o irrational_a for_o that_o all_o quantity_n commensurable_a have_v that_o proportion_n the_o one_o to_o the_o other_o which_o number_n have_v to_o number_n in_o number_n therefore_o 9_o and_o 12_o be_v commensurable_a because_o there_o be_v one_o common_a measure_n which_o measure_v they_o both_o namely_o the_o number_n 3_n first_o it_o measure_v 12_o for_o it_o be_v less_o than_o 12._o and_o be_v take_v certain_a time_n namely_o 4_o time_n it_o make_v exact_o 12_o 3_o time_n 4_o be_v 12_o it_o also_o measure_v 9_o for_o it_o be_v less_o than_o 9_o and_o also_o take_v certain_a time_n namely_o 3_o time_n it_o make_v precise_o 9_o 3_o time_n 3_o be_v 9_o likewise_o be_v it_o in_o magnitude_n if_o one_o magnitude_n measure_v two_o other_o magnitude_n those_o two_o magnitude_n so_o measure_v be_v say_v to_o be_v commensurable_a as_o for_o example_n if_o the_o line_n c_o be_v double_v do_v make_v the_o line_n b_o and_o the_o same_o line_n c_o triple_a do_v make_v the_o line_n a_o then_o be_v the_o two_o line_n a_o and_o b_o line_n or_o magnitude_n commensurable_a for_o that_o one_o measure_n namely_o the_o line_n c_o measure_v they_o both_o first_o the_o line_n c_o be_v less_o they_o the_o line_n a_o and_o alsolesse_v they_o the_o line_n b_o also_o the_o line_n c_o take_v or_o repeat_v certain_a time_n namely_o 3_o time_n make_v precise_o the_o line_n a_o and_o the_o same_o line_n c_o take_v also_o certain_a time_n namely_o two_o time_n make_v precise_o the_o line_n b._n so_o that_o the_o line_n c_o be_v a_o common_a measure_n to_o they_o both_o and_o do_v measure_v they_o both_o and_o therefore_o be_v the_o two_o line_n a_o and_o b_o line_n commensurable_a and_o so_o imagine_v you_o of_o magnitude_n of_o other_o kind_n as_o of_o superficial_a figure_n and_o also_o of_o body_n 2_o incommensurable_a magnitude_n be_v such_o which_o no_o one_o common_a measure_n do_v measure_n definition_n this_o definition_n nead_v no_o explanation_n at_o all_o other_o it_o be_v easy_o understand_v by_o the_o definition_n go_v before_o of_o line_n commensurable_a for_o contrary_n be_v make_v manifest_a by_o compare_v of_o the_o one_o to_o the_o other_o as_o if_o the_o line_n c_o or_o any_o other_o line_n oftentimes_o iterate_v do_v not_o render_v precise_o the_o line_n a_o nor_o the_o line_n b_o them_z be_v the_o line_n a_o and_o b_o incommensurable_a also_o if_o the_o line_n c_o or_o any_o other_o line_n certain_a time_n repeat_v do_v exact_o render_v the_o line_n a_o and_o do_v not_o measure_v the_o line_n b_o or_o if_o it_o measure_v the_o line_n b_o and_o measure_v not_o also_o the_o line_n a_o the_o line_n a_o and_o b_o be_v yet_o line_n incommensurable_a &_o so_o of_o other_o magnitude_n as_o of_o superficiece_n and_o body_n 3_o right_a line_n commensurable_a in_o power_n be_v such_o who_o square_n one_o and_o the_o self_n same_o superficies_n area_n or_o plat_n do_v measure_n definition_n to_o the_o declaration_n of_o this_o definition_n we_o must_v first_o call_v to_o mind_n what_o be_v understand_v &_o mean_v by_o the_o power_n of_o a_o line_n which_o as_o we_o have_v before_o in_o the_o former_a book_n note_v be_v nothing_o else_o but_o the_o square_a thereof_o or_o any_o other_o plain_a figure_n equal_a to_o the_o square_a thereof_o and_o so_o great_a power_n &_o hability_n ●s_v a_o line_n say_v to_o have_v as_o be_v the_o quantity_n of_o the_o square_n which_o it_o be_v able_a to_o describe_v or_o a_o figure_n superficial_a equal_a to_o the_o square_a
which_o be_v contain_v under_o the_o line_n ad_fw-la and_o db_o twice_o by_o a_o rational_a superficies_n for_o either_o of_o they_o be_v rational_a wherefore_o also_o the_o square_n of_o the_o line_n ac_fw-la and_o cb_o add_v together_o exceed_v the_o square_n of_o the_o line_n ad_fw-la and_o db_o add_v together_o by_o a_o rational_a superficies_n when_o yet_o each_o of_o they_o be_v a_o medial_a superficies_n which_o be_v impossible_a wherefore_o a_o line_n contain_v in_o power_n a_o rational_a and_o a_o medial_a be_v in_o one_o point_n only_o divide_v into_o his_o name_n which_o be_v require_v to_o be_v demonstrate_v ¶_o the_o 35._o theorem_a the_o 47._o proposition_n a_o line_n contain_v in_o power_n two_o medial_n be_v in_o one_o point_n only_o divide_v into_o his_o name_n svppose_v that_o ab_fw-la be_v a_o line_n contain_v in_o power_n two_o medial_n be_v divide_v into_o his_o name_n in_o the_o point_n c_o so_fw-mi that_o let_v the_o line_n ac_fw-la and_o cb_o be_v incommensurable_a in_o power_n have_v that_o which_o be_v compose_v of_o the_o square_n of_o the_o line_n ac_fw-la &_o cb_o medial_a and_o that_o also_o which_o be_v contain_v under_o the_o line_n ac_fw-la and_o cb_o medial_a and_o moreover_o incommensurable_a ●o_o that_o which_o be_v compose_v of_o the_o square_n of_o the_o line_n ac_fw-la and_o cb._n then_o i_o say_v construction_n that_o the_o line_n ab_fw-la can_v in_o no_o other_o point_n be_v divide_v into_o his_o name_n but_o only_o in_o the_o point_n c._n for_o if_o it_o be_v possible_a let_v it_o be_v divide_v into_o his_o name_n in_o the_o point_n d_o so_fw-mi that_o let_v not_o the_o line_n ac_fw-la be_v one_o and_o the_o same_o that_o be_v equal_a with_o the_o line_n db_o but_o by_o supposition_n let_v the_o line_n ac_fw-la be_v the_o great_a and_o take_v a_o rational_a line_n ef._n and_o by_o the_o 43._o of_o the_o first_o upon_o the_o line_n of_o apply_v a_o rectangle_n parallelogram_n eglantine_n equal_a to_o that_o which_o be_v compose_v of_o the_o square_n of_o the_o line_n ac_fw-la and_o cb_o and_o likewise_o upon_o the_o line_n hc_n which_o be_v equal_a to_o the_o line_n of_o apply_v the_o parallelogram_n hk_o equal_a to_o that_o which_o be_v contain_v under_o the_o line_n ac_fw-la and_o cb_o twice_o wherefore_o the_o whole_a parallelogram_n eke_o be_v equal_a to_o the_o square_n of_o the_o line_n ab_fw-la absurdity_n again_o upon_o the_o same_o line_n of_o describe_v the_o parallelogram_n el_n equal_a to_o the_o square_n of_o the_o line_n ad_fw-la and_o db._n wherefore_o the_o residue_n namely_o that_o which_o be_v contain_v under_o the_o line_n ad_fw-la and_o db_o twice_o be_v equal_a to_o the_o parallelogram_n remain_v namely_o to_o mk_o and_o forasmuch_o as_o that_o which_o be_v compose_v of_o the_o square_n of_o the_o line_n ac_fw-la and_o cb_o be_v by_o supposition_n medial_a therefore_o the_o parallelogram_n eglantine_n which_o be_v equal_a unto_o it_o be_v also_o medial_a and_o it_o be_v apply_v upon_o the_o rational_a line_n ef._n wherefore_o by_o the_o 22._o of_o the_o ten_o the_o line_n he_o be_v rational_a and_o incommensurable_a in_o length_n unto_o the_o line_n ef._n and_o by_o the_o same_o reason_n also_o the_o line_n hn_o be_v rational_a and_o incommensurable_a in_o length_n to_o the_o same_o line_n ef._n and_o forasmuch_o as_o that_o which_o be_v compose_v of_o the_o square_n of_o the_o line_n ac_fw-la and_o cb_o be_v incommensurable_a to_o that_o which_o be_v contain_v under_o the_o line_n ac_fw-la and_o cb_o twice_o for_o it_o be_v suppose_v to_o be_v incommensurable_a to_o that_o which_o be_v contain_v under_o the_o line_n ac_fw-la and_o cb_o once_o therefore_o the_o parallelogram_n eglantine_n be_v incommensurable_a to_o the_o parallelogram_n h_o ●_o wherefore_o the_o line_n eh_o also_o be_v incommensurable_a in_o length_n to_o the_o line_n hn_o and_o they_o be_v rational_a line_n wherefore_o the_o line_n eh_o and_o hn_o be_v rational_a commensurable_a in_o power_n only_o wherefore_o the_o whole_a line_n en_fw-fr be_v a_o binomial_a line_n and_o be_v divide_v into_o his_o name_n in_o the_o point_n h._n and_o in_o like_a sort_n may_v we_o prove_v that_o the_o same_o binomial_a line_n en_fw-fr be_v divide_v into_o his_o name_n in_o the_o point_n m_o and_o that_o the_o line_n eh_o be_v not_o one_o and_o the_o same_o that_o be_v equal_a with_o the_o line_n mn_o as_o it_o be_v prove_v in_o the_o end_n of_o the_o demonstration_n of_o the_o 44._o of_o this_o book_n wherefore_o a_o binomial_a line_n be_v divide_v into_o his_o name_n in_o two_o sundry_a point_n which_o be_v impossible_a by_o the_o 42._o of_o the_o ten_o wherefore_o a_o line_n contain_v in_o power_n two_o medial_n be_v not_o in_o sundry_a point_n divide_v into_o his_o name_n wherefore_o it_o be_v divide_v in_o one_o point_n only_o which_o be_v require_v to_o be_v demonstrate_v ¶_o second_a definition_n it_o be_v show_v before_o that_o of_o binomial_a line_n there_o be_v six_o kind_n line_n the_o definition_n of_o all_o which_o be_v here_o now_o set_v and_o be_v call_v second_o definition_n all_o binomial_a line_n as_o all_o other_o kind_n of_o irrational_a line_n be_v conceive_v consider_v and_o perfect_o understand_v only_o in_o respect_n of_o a_o rational_a line_n who_o part_n as_o before_o be_v teach_v be_v certain_a and_o know_v and_o may_v be_v distinct_o express_v by_o number_n unto_o which_o line_n they_o be_v compare_v this_o rational●_fw-la line_n must_v you_o ever_o have_v before_o your_o eye_n in_o all_o these_o definition_n so_o shall_v they_o all_o be_v ●asie_a enough_o pa●t●s_n a_o binomial_a line_n you_o know_v be_v make_v of_o two_o part_n or_o name_n whereof_o the_o one_o be_v great_a than_o the_o other_o wherefore_o the_o power_n or_o square_v also_o of_o the_o one_o be_v great_a than_o the_o power_n or_o square_a o●_n the_o other_o the_o three_o first_o kind_n of_o binomial_a line_n namely_o the_o first_o the_o secon●_o &_o the_o three_o be_v produce_v when_o the_o square_a of_o the_o great_a name_n or_o part_n of_o a_o binom●all_n e●cedeth_v the_o square_a of_o the_o less_o name_n or_o part_n by_o the_o square_n of_o a_o line_n which_o be_v commensurable_a in_o length_n to_o it_o namely_o to_o the_o great_a the_o three_o last_o kind_n namely_o the_o four_o the_o ●i●t_n and_o the_o six_o be_v produce_v when_o the_o square_a of_o the_o great_a name_n or_o part_n ●●●●edeth_v the_o square_a of_o the_o less_o name_n or_o part_n by_o the_o square_n of_o a_o line_n incommensurable_a in_o length_n unto_o it_o that_o be_v to_o the_o great_a part_n definition_n a_o first_o binomial_a line_n be_v who_o square_a of_o the_o great_a part_n exceed_v the_o square_a of_o t●e_z less_o part_n ●y_a the_o square_n of_o a_o line_n commensurable_a in_o length_n to_o the_o great_a part_n and_o the_o great_a part_n be_v also_o commensurable_a in_o length_n to_o t●e_z rational_a line_n first_o set_v as_o l●t_v the_o rational_a line_n first_o set_v be_v ab_fw-la who_o part_n be_v distinct_o know_v suppose_v also_o that_o the_o line_n ce_fw-fr be_v a_o binomial_a line_n who_o name_n or_o part_n let_v be_v cd_o and_o de._n and_o let_v the_o square_n of_o the_o line_n cd_o the_o great_a part_n exceed_v the_o square_n of_o the_o line_n de_fw-fr the_o less_o part_n by_o the_o square_n of_o the_o line_n fg_o which_o line_n fg_o let_v b●e_o commensurable_a in_o length_n to_o the_o line_n cd_o which_o be_v the_o great_a part_n of_o the_o binomial_a line_n and_o moreover_o let_v the_o line_n cd_o the_o great_a pa●t_n be_v commensurble_n in_o length_n to_o the_o rational_a line_n first_o set_v namely_o to_o ab_fw-la so_o by_o this_o d●●inition_n the_o binomial_a line_n ce_fw-fr be_v a_o first_o binomial_a line_n definition_n a_o second_o binomial_a line_n be_v when_o the_o square_a of_o the_o great_a part_n exceed_v the_o square_a of_o the_o less_o part_n by_o the_o square_n of_o a_o line_n commensurable_a in_o length_n unto_o it_o and_o the_o less_o part_n be_v commensurable_a in_o length_n to_o the_o rational_a line_n first_o set_v as_o suppose_v ever_o the_o rational_a line_n let_v ce_fw-fr be_v a_o binomial_a line_n divide_v in_o the_o point_n d._n the_o square_n of_o who_o great_a part_n cd_o let_v exceed_v the_o square_n of_o the_o less_o part_n de_fw-fr by_o the_o square_n of_o the_o line_n fg_o which_o line_n ●g_z let_v be_v commensurable_a in_o length_n unto_o the_o line_n cd_o t●e_z great_a p●●●_n o●_n the_o binomial_a line_n and_o let_v also_o the_o line_n de_fw-fr the_o less_o part_n of_o the_o binomial_a line_n be_v commensurable_a in_o length_n to_o the_o rational_a line_n first_o set_v ab_fw-la so_o by_o this_o definition_n the_o binomial_a line_n ce_fw-fr be_v a_o second_o binomial_a line_n ●●●●●●ition_n a_o three_o binomial_a
shall_v in_o like_a sort_n by_o the_o 14._o of_o the_o ten_o be_v in_o power_n more_o than_o the_o line_n df_o by_o the_o square_n of_o a_o line_n incommensurable_a in_o length_n to_o the_o line_n cf_o and_o then_o if_o the_o line_n ae_n be_v commensurable_a in_o length_n to_o the_o rational_a line_n the_o line_n cf_o shall_v also_o in_o like_a sort_n be_v commensurable_a in_o length_n to_o the_o same_o rational_a line_n and_o so_o either_o of_o the_o line_n ab_fw-la and_o cd_o be_v a_o four_o residual_a line_n and_o if_o the_o line_n be_v be_v commensurable_a in_o length_n to_o the_o rational_a line_n the_o line_n df_o shall_v also_o be_v commensurable_a in_o length_n to_o the_o same_o line_n and_o so_o either_o of_o the_o line_n ab_fw-la &_o cd_o be_v a_o ●i●t_o residual_a line_n and_o if_o neither_o of_o the_o line_n ae_n nor_o be_v be_v commensurable_a in_o length_n to_o the_o rational_a line_n in_o like_a sort_n neither_o of_o the_o line_n cf_o nor_o df_o shall_v be_v commensurable_a in_o length_n to_o the_o same_o rational_a line_n and_o so_o either_o of_o the_o line_n ab_fw-la &_o cd_o be_v a_o six_o residual_a line_n wherefore_o the_o line_n cd_o be_v a_o residual_a line_n of_o the_o self_n same_o order_n that_o the_o line_n ab_fw-la be_v a_o line_n therefore_o commensurable_a in_o length_n to_o a_o residual_a line_n be_v itself_o also_o a_o residual_a line_n of_o the_o self_n same_o order_n which_o be_v require_v to_o be_v prove_v as_o before_o touch_v binomial_a line_n so_o also_o touch_v residual_a line_n this_o be_v to_o be_v note_v that_o a_o line_n commensurable_a in_o length_n to_o a_o residual_a line_n be_v always_o a_o residual_a line_n of_o the_o self_n same_o order_n that_o the_o residual_a line_n be_v unto_o who_o it_o be_v commensurable_a note_n as_o have_v before_o in_o this_o 103._o proposition_n be_v prove_v but_o if_o a_o line_n be_v commensurable_a in_o power_n only_o to_o a_o residual_a line●_z than_o follow_v it_o not_o yea_o it_o be_v impossible_a that_o that_o line_n shall_v be_v a_o residual_a of_o the_o self_n same_o order_n that_o the_o residual_a line_n be_v unto_o who_o it_o be_v commensurable_a in_o power_n only_o howbeit_o those_o two_o line_n shall_v of_o necessity_n be_v both_o either_o of_o the_o three_o first_o order_n of_o resid●●ll_a line_n or_o of_o the_o three_o last_o order_n which_o be_v not_o hard_a to_o prove_v if_o you_o mark_v diligent_o the_o former_a demonstration_n and_o that_o which_o be_v speak_v of_o binomial_a line_n as_o touch_v this_o matter_n ¶_o the_o 80._o theorem_a the_o 104._o proposition_n a_o line_n commensurable_a to_o a_o medial_a residual_a line_n be_v itself_o also_o a_o medial_a residual_a line_n and_o of_o the_o self_n same_o order_n svppose_v that_o ab_fw-la be_v a_o medial_a residual_a line_n unto_o who_o let_v the_o line_n cd_o be_v commensurable_a in_o length_n and_o in_o power_n or_o in_o power_n only_o then_o i_o say_v that_o cd_o be_v also_o a_o medial_a residual_a line_n and_o of_o the_o self_n same_o order_n for_o forasmuch_o as_o the_o line_n ab_fw-la be_v a_o medial_a residual_a line_n construction_n let_v the_o line_n convenient_o join_v unto_o i●_z 〈◊〉_d be_v wherefore_o the_o line_n ae_n and_o be_v be_v medial_a commensurable_a in_o power_n only_o as_o ab_fw-la be_v to_o cd_o so_o by_o the_o 22._o of_o the_o six_o let_v be_v be_v to_o df._n and_o in_o like_a sort_n as_o in_o the_o former_a so_o also_o in_o this_o may_v we_o prove_v demonstration_n that_o the_o line_n ae_n be_v commensurable_a in_o length_n and_o in_o power_n or_o in_o power_n only_o unto_o the_o line_n cf_o &_o the_o line_n be_v 〈◊〉_d the_o line_n df._n wherefore_o by_o the_o 23._o of_o the_o ten_o 〈◊〉_d line_n cf_o be_v a_o medial_a line_n and_o the_o line_n df_o be_v also_o a_o medial_a line_n for_o that_o it_o be_v commensurable_a to_o the_o medial_a line_n be._n and_o in_o like_a sort_n the_o line_n cf_o and_o df_o be_v commensurable_a in_o power_n only_o for_o that_o they_o have_v the_o self_n same_o proportion_n the_o one_o to_o the_o other_o that_o the_o line_n ae_n and_o ebb_n have_v which_o be_v commensurable_a in_o power_n only_o wherefore_o the_o line_n cd_o be_v a_o medial_a residual_a line_n medial_a i_o say_v moreover_o that_o it_o be_v of_o the_o self_n same_o order_n that_o the_o line_n ab_fw-la be_v for_o for_o that_o as_o the_o line_n ae_n be_v to_o the_o line_n be_v so_o be_v the_o line_n cf_o to_o the_o line_n df._n but_o as_o the_o line_n ae_n be_v to_o the_o line_n be_v so_o be_v the_o square_a of_o the_o line_n ae_n to_o the_o parallelogram_n contain_v under_o the_o line_n ae_n and_o be_v by_o the_o first_o of_o the_o six_o and_o as_o the_o line_n cf_o be_v to_o the_o line_n df_o so_o be_v the_o square_a of_o the_o line_n cf_o to_o the_o parallelogram_n contain_v under_o the_o line_n cf_o and_o df._n wherefore_o as_o the_o square_n of_o the_o line_n ae_n be_v to_o the_o parallelogram_n contain_v under_o the_o line_n ae_n and_o be_v so_o be_v the_o square_a of_o the_o line_n cf_o to_o the_o parallelogram_n contain_v under_o the_o line_n cf_o and_o df._n wherefore_o alternate_o as_o the_o square_n of_o the_o line_n ae_n be_v to_o the_o square_n of_o the_o line_n cf_o so_o be_v the_o parallelogram_n contain_v under_o the_o line_n ae_n and_o be_v to_o the_o parallelogram_n contain_v under_o the_o ●ines_n cf_o and_o df._n but_o the_o square_n of_o the_o line_n ae_n be_v commensurable_a to_o the_o square_n of_o the_o line_n cf_o for_o the_o line_n ae_n be_v commensurable_a to_o the_o line_n cf_o wherefore_o also_o the_o parallelogram_n contain_v under_o the_o line_n ae_n and_o be_v be_v commensurable_a to_o the_o parallelogram_n contain_v under_o the_o line_n cf_o and_o df._n wherefore_o if_o the_o parallelogram_n contain_v under_o the_o line_n ae_n and_o ebb_n be_v rational_a the_o parallelogram_n also_o contain_v under_o the_o line_n cf_o and_o fd_o shall_v be_v rational_a and_o then_o either_o of_o the_o line_n ab_fw-la and_o cd_o be_v a_o first_o medial_a residual_a line_n but_o if_o the_o parallelogram_n contain_v under_o the_o line_n ae_n and_o be_v be_v medial_a the_o parallelogram_n also_o contain_v under_o the_o line_n cf_o and_o fd_o shall_v be_v also_o medial_a by_o the_o corollary_n of_o the_o 23._o of_o the_o ten_o and_o so_o either_o of_o the_o line_n ab_fw-la and_o cd_o be_v a_o second_o medial_a residual_a line_n wherefore_o the_o line_n cd_o be_v a_o medial_a residual_a line_n of_o the_o self_n same_o order_n that_o the_o line_n ab_fw-la be_v a_o line_n therefore_o commensurable_a to_o a_o medial_a residual_a line_n be_v itself_o also_o a_o medial_a residual_a line_n of_o the_o self_n same_o order_n which_o be_v require_v to_o be_v demonstrate_v this_o theorem_a be_v understand_v general_o that_o whether_o a_o line_n be_v commensurable_a in_o length_n &_o in_o power_n or_o in_o power_n only_o to_o a_o medial_a residual_a line_n it_o be_v itself_o also_o a_o medial_a residual_a line_n and_o of_o the_o self_n same_o order_n which_o thing_n also_o be_v to_o be_v understand_v of_o the_o three_o theorem_n which_o follow_v an_o other_o demonstration_n after_o campane_n suppose_v that_o a_o be_v a_o medial_a residual_a line_n unto_o who_o let_v the_o line_n b_o be_v commensurable_a in_o length_n or_o in_o power_n only_o and_o take_v a_o rational_a line_n cd_o unto_o which_o apply_v the_o parallelogram_n ce_fw-fr equal_a to_o the_o square_n of_o the_o line_n a_o construction_n and_o unto_o the_o line_n fe_o which_o be_v equal_a to_o the_o line_n cd_o apply_v the_o parallelogram_n f●_n equal_a to_o the_o square_n of_o the_o line_n b._n now_o then_o the_o parallelogram_n ce_fw-fr and_o fg_o shall_v be_v commensurable_a demonstration_n for_o that_o the_o line_n a_o b_o be_v commensurable_a in_o power_n wherefore_o by_o the_o 1._o of_o the_o six_o and_o 10._o of_o this_o book_n th●_z line_n de_fw-fr and_o fg_o be_v commensurable_a in_o length_n now_o than_o if_o a_o be_v a_o first_o medial_a residual_a line_n then_o be_v the_o line_n de_fw-fr a_fw-fr second_v residual_a line_n by_o the_o 98._o of_o this_o book_n and_o if_o the_o line_n a_o be_v a_o s●cond_o medial_a residual_a line_n then_o be_v the_o line_n ●●_o ●_z a_o three_o residual_a line_n by_o the_o 99_o of_o this_o book_n but_o if_o de_fw-fr be_fw-mi a_o second_o residual_a line_n g●_n also_o shall_v be_v a_o second_o residual_a line_n by_o the_o ●03_n of_o this_o book_n and_o if_o de_fw-fr be_fw-mi a_o three_o residual_a line_n ge_z also_o shall_v by_o the_o same_o be_v also_o a_o three_o residual_a line_n wherefore_o it_o follow_v by_o the_o 9●_n and_o 93._o of_o this_o book_n that_o b_o be_v either_o a_o first_o
measure_v the_o square_a number_n produce_v of_o ef._n wherefore_o also_o by_o the_o 14._o of_o the_o eight_o the_o number_n g_z measure_v the_o number_n of_o and_o the_o number_n g_o also_o measure_v itself_o wherefore_o the_o number_n g_z measure_v these_o number_n of_o and_o g_z when_o yet_o they_o be_v prime_a the_o one_o to_o the_o other_o which_o be_v impossible_a wherefore_o the_o diameter_n a_o be_v not_o commensurable_a in_o length_n to_o the_o side_n b._n wherefore_o it_o be_v incommensurable_a which_o be_v require_v to_o be_v demonstrate_v an_o other_o demonstration_n after_o flussas_n suppose_v that_o upon_o the_o line_n ab_fw-la be_v describe_v a_o square_n who_o diameter_n let_v be_v the_o line_n ac_fw-la then_o i_o say_v that_o the_o side_n ab_fw-la be_v incommensurable_a in_o length_n unto_o the_o diameter_n ac_fw-la forasmuch_o as_o the_o line_n ab_fw-la and_o bc_o be_v equal_a therefore_o the_o square_a of_o the_o line_n ac_fw-la be_v double_a to_o the_o square_n of_o the_o line_n ab_fw-la by_o the_o 47._o of_o the_o first_o take_v by_o the_o 2._o of_o the_o eight_o number_n how_o many_o soever_o in_o continual_a proportion_n from_o unity_n and_o in_o the_o proportion_n of_o the_o square_n of_o the_o line_n ab_fw-la and_o ac_fw-la which_o let_v be_v the_o number_n d_o e_o f_o g._n and_o forasmuch_o as_o the_o first_o from_o unity_n namely_o e_o be_v no_o square_a number_n for_o that_o it_o be_v a_o prime_a number_n neither_o be_v also_o any_o other_o of_o the_o say_a number_n a_o square_a number_n except_o the_o three_o from_o unity_n and_o so_o all_o the_o rest_n leving_fw-mi one_o between_o by_o the_o 10._o of_o the_o nine_o wherefore_o d_z be_v to_o e_o or_o e_o to_o fletcher_n or_o fletcher_n to_o g_z in_o that_o proportion_n that_o a_o square_a number_n be_v to_o a_o number_n not_o square_a wherefore_o by_o the_o corollary_n of_o the_o 25._o of_o the_o eight_o they_o be_v not_o in_o that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n be_v to_o a_o square_a number_n wherefore_o neither_o also_o have_v the_o square_n of_o the_o line_n ab_fw-la and_o ac_fw-la which_o be_v in_o the_o same_o proportion_n that_o porportion_n that_o a_o square_a number_n have_v to_o a_o square_a number_n wherefore_o by_o the_o 9_o of_o this_o book_n their_o side_n namely_o the_o side_n ab_fw-la and_o the_o diameter_n ac_fw-la be_v incommensurable_a in_o length_n the_o one_o to_o the_o other_o which_o be_v require_v to_o be_v prove_v this_o demonstration_n i_o think_v good_a to_o add_v for_o that_o the_o former_a demonstration_n seem_v not_o so_o full_a and_o they_o be_v think_v of_o some_o to_o be_v none_o of_o theon_n as_o also_o the_o proposition_n to_o be_v none_o of_o euclides_n here_o follow_v a_o instruction_n by_o some_o studious_a and_o skilful_a grecian_a perchance_o theon_n which_o teach_v we_o of_o far_a use_n and_o fruit_n of_o these_o irrational_a line_n see_v that_o there_o be_v find_v out_o right_a line_n incommensurable_a in_o length_n the_o one_o to_o the_o ●ther_n as_o the_o line_n a_o and_o b_o there_o may_v also_o be_v find_v out_o many_o other_o magnitude_n have_v length_n and_o breadth_n such_o as_o be_v plain_a superficiece_n which_o shall_v be_v incommensurable_a the_o one_o to_o the_o other_o for_o if_o by_o the_o 13._o of_o the_o six_o between_o the_o line_n a_o and_o b_o there_o be_v take_v the_o mean_a proportional_a line_n namely_o c_z then_o by_o the_o second_o corollary_n of_o the_o 20._o of_o the_o six_o as_o the_o line_n a_o be_v to_o the_o line_n b_o so_o be_v the_o figure_n describe_v upon_o the_o line_n a_o to_o the_o figure_n describe_v upon_o the_o line_n c_o be_v both_o like_a and_o in_o like_a sort_n describe_v that_o be_v whether_o they_o be_v square_n which_o be_v always_o like_o the_o one_o to_o the_o other_o or_o whether_o they_o be_v any_o other_o like_o rectiline_a figure_n or_o whether_o they_o be_v circle_n about_o the_o diameter_n a_o and_o c._n for_o circle_n have_v that_o proportion_n the_o one_o to_o the_o other_o that_o the_o square_n of_o their_o diameter_n have_v by_o the_o 2._o of_o the_o twelve_o wherefore_o by_o the_o second_o part_n of_o the_o 10._o of_o the_o ten_o the_o ●_z describe_v upon_o the_o line_n a_o and_o c_o being_n like_o and_o in_o like_a sort_n describe_v be_v incommensurable_a the_o one_o to_o the_o other_o wherefore_o by_o this_o mean_n there_o be_v find_v out_o superficieces_o incommensurable_a the_o one_o to_o the_o other_o in_o like_a sort_n there_o may_v be_v find_v out_o figure_n commensurable_a the_o one_o to_o the_o other_o if_o you_o put_v the_o line_n a_o and_o b_o to_o be_v commensurable_a in_o length_n the_o one_o to_o the_o other_o and_o see_v that_o it_o be_v so_o now_o let_v we_o also_o prove_v that_o even_o in_o soli●es_n also_o or_o body_n there_o be_v some_o commensurable_a the_o one_o to_o the_o other_o and_o other_o some_o incommensurable_a the_o one_o to_o the_o other_o for_o if_o from_o each_o of_o the_o square_n of_o the_o line_n a_o and_o b_o or_o from_o any_o other_o rectiline_a figure_n equal_a to_o these_o square_n be_v erect_v solid_n of_o equal_a altitude_n whether_o those_o solid_n be_v compose_v of_o equidistant_a supersiciece_n or_o whether_o they_o be_v pyramid_n or_o prism_n thos●_n solid_n s●_n erected_a shall_v be_v in_o that_o proportion_n the_o one_o to_o the_o other_o that_o their_o base_n be_v by_o the_o 32._o o●_n the_o eleven_o and_o 5._o and_o 6._o of_o the_o twelve_o howbeit_o there_o be_v no_o such_o proposition_n concern_v prism_n and_o so_o if_o the_o base_n of_o the_o solid_n b●_z commensurable_a the_o one_o to_o the_o other_o the_o solid_n also_o shall_v be_v commensurable_a the_o one_o to_o the_o other_o and_o if_o the_o base_n be_v incommensurable_a the_o one_o to_o the_o other_o the_o solid_n also_o shall_v be_v incommensurable_a the_o one_o to_o the_o other_o by_o the_o 10._o of_o the_o ten_o and_o if_o there_o be_v two_o circle_n a_o and_o b_o and_o upon_o each_o of_o the_o circle_n be_v erect_v cones_n or_o cilinder_n of_o equal_a altitude_n those_o cones_n &_o cilinder_n s●all_v be_v in_o that_o proportion_n the_o one_o to_o the_o other_o that_o the_o circle_n be_v which_o be_v their_o base_n by_o the_o 11._o of_o the_o twelve_o and_o so_o if_o the_o circle_n be_v commensurable_a the_o one_o to_o the_o other_o the_o cones_n and_o cilinder_n also_o shall_v be_v commensurable_a the_o one_o to_o the_o other_o but_o if_o the_o circle_n be_v incommensurable_a the_o one_o to_o the_o other_o the_o cones_n also_o and_o cilinder_n shall_v be_v incommensurable_a the_o one_o to_o the_o other_o by_o the_o 10._o of_o the_o ten_o wherefore_o it_o be_v manifest_a that_o not_o only_o in_o line_n and_o super●icieces_n but_o also_o in_o solid_n or_o body_n be_v find_v commensurabilitie_n or_o incommensurability_n a_o advertisement_n by_o john_n dee_n although_o this_o proposition_n be_v by_o euclid_n to_o this_o book_n allot_v as_o by_o the_o ancient_a graecian_n publish_v under_o the_o name_n of_o aristoteles_n 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d it_o will_v seem_v to_o be_v and_o also_o the_o property_n of_o the_o same_o agreeable_a to_o the_o matter_n of_o this_o book_n and_o the_o proposition_n itself_o so_o famous_a in_o philosophy_n and_o logic_n as_o it_o be_v will_v in_o manner_n crave_v his_o elemental_a place_n in_o this_o ten_o book_n yet_o the_o dignity_n &_o perfection●_n of_o mathematical_a method_n can_v not_o allow_v it_o here_o as_o in_o due_a order_n follow_v but_o most_o apt_o after_o the_o 9_o proposition_n of_o this_o book_n as_o a_o corollary_n of_o the_o last_o part_n thereof_o and_o undoubted_o the_o proposition_n have_v for_o this_o 2000_o year_n be_v notable_o regard_v among_o the_o greek_n philosopher_n and_o before_o aristotle_n time_n be_v conclude_v with_o the_o very_a same_o inconvenience_n to_o the_o gaynesayer_n that_o the_o first_o demonstration_n here_o induce_v namely_o odd_a number_n to_o be_v equal_a to_o even_o as_o may_v appear●_n in_o aristotle_n work_n name_v analitica_fw-la prima_fw-la the_o first_o book_n and_o 40._o chapter_n but_o else_o in_o very_a many_o place_n of_o his_o work_n he_o make_v mention_n of_o the_o proposition_n evident_a also_o it_o be_v that_o euclid_n be_v about_o aristotle_n time_n and_o in_o that_o age_n the_o most_o excellent_a geometrician_n among_o the_o greek_n wherefore_o see_v it_o be_v so_o public_a in_o his_o time_n so_o famous_a and_o so_o appertain_v to_o the_o property_n of_o this_o book_n it_o be_v most_o likely_a both_o to_o be_v know_v to_o euclid_n and_o also_o to_o have_v be_v by_o he_o in_o apt_a order_n place_v but_o of_o the_o disorder_v of_o it_o can_v remain_v no_o doubt_n if_o you_o consider_v in_o zamberts_n translation_n
the_o word_n of_o psellus_n in_o his_o epitome_n of_o geometry_n where_o he_o entreat_v of_o the_o production_n and_o constitution_n of_o these_o body_n his_o word_n be_v these_o psellus_n all_o rectiline_v figure_n be_v erect_v upon_o their_o plain_n or_o base_n by_o right_a angle_n make_v prism_n who_o perceive_v not_o but_o that_o a_o pentagon_n erect_v upon_o his_o base_a of_o ●ive_a side_n make_v by_o his_o motion_n a_o side_v column_n of_o five_o side_n likewise_o a_o hexagon_n erect_v at_o right_a angle_n produce_v a_o column_n have_v six_o side_n and_o so_o of_o all_o other_o rectillne_v figure_n all_o which_o solid_n or_o body_n so_o produce_v whether_o they_o be_v side_v column_n or_o parallelipipedon_n be_v here_o in_o most_o plain_a word_n of_o this_o excellent_a and_o ancient_a greek_a author_n psellus_n call_v prism_n wherefore_o if_o the_o definition_n of_o a_o prism_n give_v of_o euclid_n shall_v extend_v itself_o so_o large_o as_o flussas_n imagine_v and_o shall_v include_v such_o figure_n or_o body_n as_o he_o note_v he_o ought_v not_o yet_o for_o all_o that_o so_o much_o to_o be_v offend_v and_o so_o narrow_o to_o have_v seek_v fault_n for_o euclid_n in_o so_o define_v may_v have_v that_o meaning_n &_o sense_n of_o a_o prism_n which_o psellus_n have_v so_o you_o see_v that_o euclid_n may_v be_v defend_v either_o of_o these_o two_o way_n either_o by_o that_o that_o the_o definition_n extend_v not_o to_o these_o figure_n and_o so_o not_o to_o be_v over_o general_n nor_o stretch_v far_o than_o it_o ought_v or_o else_o by_o that_o that_o if_o it_o shall_v stretch_v so_o far_o it_o be_v not_o so_o heinous_a for_o that_o as_o you_o see_v many_o have_v tak●_n it_o in_o that_o sense_n in_o deed_n common_o a_o prism_n be_v take_v in_o that_o signification_n and_o meaning_n in_o which_o campa●●●_n flussas_n and_o other_o take_v it_o in_o which_o sense_n it_o seem_v also_o that_o in_o diverse_a proposition_n in_o these_o book_n follow_v it_o ought_v of_o 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de_fw-fr sacro_fw-la busco_n in_o his_o book_n of_o the_o sphere_n busco_n of_o this_o definition_n which_o he_o take_v out_o of_o euclid_n do_v well_o collect_n but_o it_o be_v to_o be_v note_v and_o take_v heed_n of_o that_o none_o be_v deceive_v by_o the_o definition_n of_o a_o sphere_n give_v by_o johannes_n de_fw-fr sacro_fw-la busco_n a_o sphere_n say_v he_o be_v the_o passage_n or_o move_v of_o the_o circumference_n of_o a_o semicircle_n till_o it_o return_v unto_o the_o place_n where_o it_o begin_v which_o agree_v not_o with_o euclid_n euclid_n plain_o say_v that_o a_o sphere_n be_v the_o passage_n or_o motion_n of_o a_o semicircle_n and_o not_o the_o passage_n or_o motion_n of_o the_o circumference_n of_o a_o semicircle_n neither_o can_v it_o be_v true_a that_o the_o circumference_n of_o a_o semicircle_n which_o be_v a_o line_n shall_v describe_v a_o body_n it_o be_v before_o note_v that_o every_o quantity_n move_v describe_v and_o produce_v the_o quantity_n next_o unto_o it_o 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at_o all_o adventure_n namely_o d_o five_o g_o s_o and_o a_o right_a line_n be_v draw_v from_o the_o point_n d_o to_o the_o point_n g_o and_o a_o other_o from_o the_o point_n five_o to_o the_o point_n s._n wherefore_o by_o the_o 7._o of_o the_o eleven_o the_o line_n dg_o and_o we_o be_v in_o one_o and_o the_o self_n same_o plain_a superficies_n and_o forasmuch_o as_o the_o line_n de_fw-fr be_v a_o parallel_n to_o the_o line_n bg_o therefore_o by_o the_o 24._o of_o the_o first_o the_o angle_n edt_n be_v equal_a to_o the_o angle_n bgt_fw-mi for_o they_o be_v alternate_a angle_n and_o likewise_o the_o angle_n dtv_n be_v equal_a to_o the_o angle_n gts_fw-fr now_o then_o there_o be_v two_o triangle_n that_o be_v dtv_n and_o gts_fw-fr have_v two_o angle_n of_o the_o one_o equal_a to_o two_o angle_n of_o the_o other_o and_o one_o side_n of_o the_o one_o equal_a to_o one_o side_n of_o the_o other_o namely_o the_o side_n which_o subtend_v the_o equal_a angle_n that_o be_v the_o side_n dv_o to_o 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the_o angle_n of_o the_o solid_a be_v equal_a equilater_n &_o equiangle_n by_o the_o 26._o of_o the_o first_o wherefore_o it_o follow_v that_o the_o plain_a superficies_n which_o cut_v the_o parallelipipedon_n do_v make_v the_o part_n of_o the_o base_n on_o the_o opposite_a side_n equal_a and_o equiangle_n and_o therefore_o like_a and_o equal_a both_o in_o multitude_n and_o in_o magnitude_n wherefore_o the_o two_o solid_a section_n of_o that_o solid_a shall_v be_v equal_a and_o like_a by_o the_o 8._o definition_n of_o this_o book_n and_o now_o that_o no_o other_o plain_a superficies_n beside_o that_o which_o be_v extend_v by_o the_o centre_n divide_v the_o parallelipipedon_n into_o two_o equal_a part_n it_o be_v manifest_a if_o unto_o the_o plain_a superficies_n which_o be_v not_o extend_v by_o the_o centre_n we_o extend_v by_o the_o centre_n a_o parallel_n plain_a superficies_n by_o the_o corollary_n of_o the_o 15._o of_o this_o book_n for_o forasmuch_o as_o that_o superficies_n 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line_n equal_a to_o the_o foresay_a parallel_n line_n which_o superficiece_n must_v also_o be_v divide_v into_o two_o equal_a part_n by_o parallel_a line_n draw_v by_o their_o centre_n and_o must_v cut_v the_o one_o the_o other_o by_o these_o parallel_a line_n and_o for_o the_o diameter_n of_o this_o body_n extend_v a_o thread_n from_o one_o angle_n in_o the_o base_a of_o the_o solid_a to_o his_o opposite_a angle_n which_o shall_v pass_v by_o the_o centre_n of_o the_o parallelipipedon_n as_o do_v the_o line_n dg_o in_o the_o figure_n before_o describe_v in_o the_o plain_n and_o draw_v in_o the_o base_a and_o the_o opposite_a superficies_n unto_o it_o diagonal_a line_n from_o the_o angle_n from_o which_o be_v extend_v the_o diameter_n of_o the_o solid_a as_o in_o the_o former_a description_n be_v the_o line_n bg_o and_o de._n and_o when_o you_o have_v thus_o describe_v this_o body_n compare_v it_o with_o the_o former_a demonstration_n and_o it_o will_v make_v it_o very_o plain_a unto_o you_o so_o your_o letter_n agree_v with_o the_o letter_n of_o the_o figure_n describe_v in_o the_o book_n and_o this_o description_n will_v plain_o set_v forth_o unto_o you_o the_o corollary_n follow_v that_o proposition_n for_o where_o as_o to_o the_o understanding_n of_o the_o demonstration_n of_o the_o proposition_n the_o superficiece_n put_v within_o the_o body_n be_v extend_v by_o parallel_a line_n draw_v by_o the_o centre_n of_o the_o base_n of_o the_o parallelipipedon_n to_o the_o understanding_n of_o the_o say_a corollary_n you_o may_v extend_v a_o superficies_n by_o any_o other_o line_n draw_v in_o the_o say_a base_n so_o that_o yet_o it_o pass_v through_o the_o midst_n of_o the_o thread_n which_o be_v suppose_v to_o be_v the_o centre_n of_o the_o parallelipipedon_n ¶_o the_o 35._o theorem_a the_o 40._o proposition_n if_o there_o be_v
last_o proposition_n in_o the_o second_o book_n and_o also_o of_o the_o 31._o in_o the_o six_o book_n ¶_o a_o problem_n 5._o two_o unequal_a circle_n be_v give_v to_o find_v a_o circle_n equal_a to_o the_o excess_n of_o the_o great_a to_o the_o less_o suppose_v the_o two_o unequal_a circle_n give_v to_o be_v abc_n &_o def_n &_o let_v abc_n be_v the_o great_a construction_n who_o diameter_n suppose_v to_o be_v ac_fw-la &_o the_o diameter_n of_o def_n suppose_v to_o be_v df._n i_o say_v a_o circle_n must_v be_v find_v equal_a to_o that_o excess_n in_o magnitude_n by_o which_o abc_n be_v great_a th●_z def_n by_o the_o first_o of_o the_o four_o in_o the_o circle_n abc_n apply_v a_o right_a line_n equal_a to_o df_o who_o one_o end_n let_v be_v at_o c_o and_o the_o other_o let_v be_v at_o b._n fron_n b_o to_o a_o draw_v a_o right_a line_n by_o the_o 30._o of_o the_o three_o it_o may_v appear_v demonstration_n that_o abc_n be_v a_o right_a angle_n and_o thereby_o abc_n the_o triangle_n be_v rectangle_v wherefore_o by_o the_o first_o of_o the_o two_o corollary_n here_o before_o the_o circle_z abc_n be_v equal_a to_o the_o circle_n def_n for_o bc_o by_o construction_n be_v equal_a to_o df_o and_o more_o over_o to_o the_o circle_n who_o diameter_n be_v ab_fw-la that_o circle_n therefore_o who_o diameter_n be_v ab_fw-la be_v the_o circle_n contain_v the_o magnitude_n by_o which_o abc_n be_v great_a than_o def_n wherefore_o two_o unequal_a circle_n be_v give_v we_o have_v find_v a_o circle_n equal_a to_o the_o excess_n of_o the_o great_a to_o the_o less_o which_o ought_v to_o be_v do_v a_o problem_n 6._o a_o circle_n be_v give_v to_o find_v two_o circle_n equal_a to_o the_o same_o which_o find_v circle_n shall_v have_v the_o one_o to_o the_o other_o any_o proportion_n give_v in_o two_o right_a line_n suppose_v abc_n a_o circle_n give_v and_o the_o proportion_n give_v let_v it_o be_v that_o which_o be_v between_o the_o two_o right_a line_n d_z and_o e._n i_o say_v that_o two_o circle_n be_v to_o be_v find_v equal_a to_o abc_n and_o with_o all_o one_o to_o the_o other_o construction_n in_o the_o proportion_n of_o d_o to_o e._n let_v the_o diameter_n of_o abc_n be_v ac_fw-la as_z d_z be_v to_o e_o so_o let_v ac_fw-la be_v divide_v by_o the_o 10._o of_o the_o six_o in_o the_o point_n f._n at_o fletcher_n to_o the_o line_n ac_fw-la let_v a_o perpendicular_a be_v draw_v fb_o and_o let_v it_o mete_v the_o circumference_n at_o the_o point_n b._n from_o the_o point_n b_o to_o the_o point_v a_o and_o c_o let_v right_a line_n be_v draw_v ba_o and_o bc._n i_o say_v that_o the_o circle_n who_o diameter_n be_v the_o line_n basilius_n and_o bc_o be_v equal_a to_o the_o circle_n abc_n and_o that_o those_o circle_n have_v to_o their_o diameter_n the_o line_n basilius_n and_o bc_o be_v one_o to_o the_o other_o in_o the_o proportion_n of_o the_o line_n d_o to_o the_o line_n e._n for_o first_o that_o they_o be_v equal_a it_o be_v evident_a by_o reason_n that_o abc_n be_v a_o triangle_n rectangle_n wherefore_o by_o the_o 47._o of_o the_o first_o the_o square_n of_o basilius_n and_o bc_o be_v equal_a to_o the_o square_n of_o ac_fw-la and_o so_o by_o this_o second_o it_o be_v manife_a the_o two_o circle_n to_o be_v equal_a to_o the_o circle_n abc_n second_o as_o d_o be_v to_o ●_o so_o be_v of_o to_o fc_n by_o construction_n and_o as_o the_o line_n of_o be_v to_o the_o line_n fc_o so_o be_v the_o square_a of_o the_o line_n ●a_o to_o the_o square_n of_o the_o line_n bc._n which_o thing_n we_o will_v brief_o prove_v thus_o the_o parallelogram_n contain_v under_o ac_fw-la and_o of_o use_n be_v equal_a to_o the_o square_n of_o basilius_n by_o the_o lemma_n after_o the_o 32._o of_o the_o ten_o book_n and_o by_o the_o same_o lemma_n or_o assumpt_n the_o parallelogram_n contain_v under_o ac_fw-la and_o ●c_z be_v equal_a to_o the_o square_n of_o the_o line_n bc._n wherefore_o as_o the_o first_o parallelogram_n have_v itself_o to_o the_o second●_n so_o have_v the_o square_a of_o basilius_n equal_a to_o the_o first_o parallelogram_n itself_o to_o the_o square_n of_o bc_o equal_a to_o the_o second_o parallelogram_n but_o both_o the_o parallelogram_n have_v one_o height_n namely_o the_o line_n ac_fw-la and_o base_n the_o line_n of_o and_o fc_n wherefore_o as_o of_o be_v to_o fc_n so_o be_v the_o parallelog●amme_n contain_v under_o ac_fw-la of_o to_o the_o parallelogram_n contain_v under_o ac_fw-la fc_fw-la by_o the_o fi●st_n of_o the_o six_o and_o therefore_o as_o of_o be_v to_o fc_n so_o be_v the_o square_a of_o basilius_n to_o the_o square_n of_o bc._n and_o as_o the_o square_n of_o basilius_n be_v to_o the_o square_n of_o bc_o so_o be_v the_o circle_n who_o diameter_n be_v basilius_n to_o the_o circle_n who_o diameter_n be_v bc_o by_o this_o second_o of_o the_o twelve_o wherefore_o the_o circle_n who_o diameter_n be_v basilius_n be_v to_o the_o circle_n who_o diameter_n be_v bc_o as_o d_z be_v to_o e._n and_o before_o we_o prove_v they_o equal_a to_o the_o circle_n abc_n wher●fore_o a_o circle_n be_v give_v we_o have_v find_v two_o circle_n equal_a to_o the_o same_o which_o have_v the_o one_o to_o the_o other_o any_o proportion_n give_v in_o two_o right_a line_n which_o ought_v to_o be_v do_v note_n addition_n he●e_o may_v you_o perceive_v a_o other_o way_n how_o to_o execute_v my_o first_o problem_n for_o if_o you_o make_v a_o right_a angle_n contain_v of_o the_o diameter_n give_v as_o in_o this_o figure_n suppose_v they_o basilius_n and_o bc_o and_o then_o subtend_v the_o right_a angle_n with_o the_o line_n ac_fw-la and_o from_o the_o right_a angle_n let_v fall_v a_o line_n perpendicular_a to_o the_o base_a ac_fw-la that_o perpendicular_a at_o the_o point_n of_o his_o fall_n divide_v ac_fw-la into_o of_o and_o fc_n of_o the_o proportion_n require_v a_o corollary_n it_o follow_v of_o thing_n manifest_o prove_v in_o the_o demonstration_n of_o this_o problem_n that_o in_o a_o triangle_n rectangle_n if_o from_o the_o right_a angle_n to_o the_o base_a a_o perpendicular_a be_v let_v fall_v the_o same_o perpendicular_a cut_v the_o base_a into_o two_o part_n rectangle_n in_o that_o proportion_n one_o to_o the_o other_o that_o the_o square_n of_o the_o righ●_n line_n contain_v the_o right_a angle_n be_v in_o one_o to_o the_o other_o those_o on_o the_o one_o side_n the_o perpendicular_a be_v compare_v to_o those_o on_o the_o other_o both_o square_a and_o segment_n a_o problem_n 7._o between_o two_o circle_n give_v to_o find_v a_o circle_n middle_a proportional_a let_v the_o two_o circle_n give_v be_v acd_o and_o bef_a i_o say_v that_o a_o circle_n be_v to_o be_v find_v which_o between_o acd_a and_o bef_n be_v middle_a proportional_a construction_n let_v the_o diameter_n of_o acd_a be_v ad_fw-la and_o of_o bef_n let_v b●_n be_v the_o diameter_n between_o ad_fw-la and_o bf_o find_v a_o line_n middle_a proportional_a by_o the_o 13._o of_o the_o six_o which_o let_v be_v hk_a i_o say_v that_o a_o circle_n who_o diameter_n be_v hk_n be_v middle_a proportional_a between_o acd_a and_o bef_a to_o ad_fw-la hk_o and_o bf_o three_o right_a line_n in_o continual_a proportion_n by_o construction_n let_v a_o four_o line_n be_v find_v to_o which_o bf_o shall_v have_v that_o proportion_n that_o ad_fw-la have_v to_o hk_n by_o the_o 12._o of_o the_o six_o &_o let_v that_o line_n be_v ●_o demonstration_n it_o be_v manifest_a that_o the_o ●ower_a line_n ad_fw-la hk_o bf_o and_o l_o be_v in_o continual_a proportion_n for_o by_o construction_n as_o ad_fw-la be_v to_o hk_n so_o be_v b●_n to_o l._n and_o by_o construction_n on_o as_z ad_fw-la be_v to_o hk_n so_o be_v hk_v to_o bf_o wherefore_o hk_n be_v to_o bf_o as_o bf_o be_v to_o l_o by_o the_o 11._o of_o the_o five_o wherefore_o the_o 4._o line_n be_v in_o continual_a proportion_n wherefore_o as_o the_o first_o be_v to_o the_o three_o that_o be_v ad_fw-la to_o bf_o so_o be_v the_o square_a of_o the_o first_o to_o the_o square_n of_o the_o second_o that_o be_v the_o square_a of_o ad_fw-la to_o the_o square_n of_o hk_n by_o the_o corollary_n of_o the_o 20._o of_o the_o six_o and_o by_o the_o same_o corollary_n as_o hk_n be_v to_o l_o so_o be_v the_o square_a of_o hk_n to_o the_o square_n of_o bf_o but_o by_o alternate_a proportion_n the_o line_n ad_fw-la be_v to_o bf_o as_o hk_n be_v to_o l_o wherefore_o the_o square_a of_o ad_fw-la be_v to_o the_o square_n of_o hk_n as_o the_o square_n of_o hk_n be_v to_o the_o square_n of_o bf_o wherefore_o the_o square_a of_o hk_n be_v middle_a proportional_a between_o the_o square_n of_o ad_fw-la and_o the_o square_n of_o bf_o but_o as_o the_o square_n be_v
triangle_n abc_n acd_o &_o cde_o and_o likewise_o the_o base_a fghkl_o into_o these_o triangle_n fgh_o fhl_n and_o hkl_n and_o imagine_v that_o upon_o every_o one_o of_o those_o triangle_n be_v set_v a_o pyramid_n of_o equal_a altitude_n with_o the_o two_o pyramid_n put_v at_o the_o beginning_n demonstration_n and_o for_o that_o as_o the_o triangle_n abc_n be_v to_o the_o triangle_n adc_o so_o be_v the_o pyramid_n abcm_n to_o the_o pyramid_n adcm_n by_o the_o 5._o of_o this_o book_n wherefore_o by_o composition_n by_o the_o 18._o of_o the_o five_o as_o the_o four_o side_v figure_n abcd_o be_v to_o the_o triangle_n acd_o so_o be_v the_o pyramid_n abcdm_n to_o the_o pyramid_n acdm_n but_o as_o the_o triangle_n acd_o be_v to_o the_o triangle_n cde_o so_o be_v the_o pyramid_n acdm_n to_o the_o pyramid_n cdem_fw-la wherefore_o of_o equality_n by_o the_o 22._o of_o the_o five_o as_o the_o base_a abcd_o be_v to_o th●_z base_a cde_o so_o be_v the_o pyramid_n abcdm_n to_o the_o pyramid_n cdem_fw-la wherefore_o again_o by_o composition_n by_o the_o 18._o of_o the_o five_o as_o the_o base_a abcde_o be_v to_o the_o base_a cde_o so_o be_v the_o pyramid_n abcedm_n to_o the_o pyramid_n cdem_fw-la and_o by_o the_o same_o reason_n also_o as_o the_o base_a fghkl_o be_v to_o the_o base_a hkl_n so_o be_v the_o pyramid_n fghkln_v to_o the_o pyramid_n hkln_n and_o forasmuch_o as_o there_o be_v two_o pyramid_n cdem_n and_o hkln_n have_v triangle_n to_o their_o base_n and_o be_v under_o one_o and_o the_o self_n same_o altitude_n therefore_o by_o the_o 5._o of_o the_o twelve_o as_o the_o base_a cde_o be_v to_o the_o base_a hkl_n so_o be_v the_o pyramid_n cdem_n to_o the_o pyramid_n hkln_n now_o for_o that_o as_o the_o base_a abce_v be_v to_o the_o base_a cde_o so_o be_v the_o pyramid_n abcedm_n to_o the_o pyramid_n cdem_fw-la but_o as_o the_o base_a cde_o be_v to_o the_o base_a hkl_n so_o be_v the_o pyramid_n cdem_n to_o the_o pyramid_n hkln_n wherefore_o of_o equality_n by_o the_o 22._o of_o the_o five_o as_o the_o base_a abce_v be_v to_o the_o base_a hkl_n so_o be_v the_o pyramid_n abcedm_n to_o the_o pyramid_n hkln_n but_o also_o as_o the_o base_a hkl_n be_v the_o base_a fghkl_o so_o be_v the_o pyramid_n hkln_v to_o to_o the_o pyramid_n fghkln_n wherefore_o again_o of_o equality_n by_o the_o 22._o of_o the_o five_o as_o the_o base_a abce_v be_v to_o the_o base_a fghkl_o so_o be_v the_o pyramid_n abcedm_n to_o the_o pyramid_n fghkln_n wherefore_o pyramid_n consist_v under_o one_o and_o the_o self_n same_o altitude_n and_o have_v polygonon_n figure_n to_o their_o base_n be_v in_o that_o proportion_n the_o one_o to_o the_o other_o that_o their_o base_n be_v which_o be_v require_v to_o be_v prove_v the_o 7._o theorem_a the_o 7._o proposition_n every_o prism_n have_v a_o triangle_n to_o his_o base_a may_v be_v divide_v into_o three_o pyramid_n equal_a the_o one_o to_o the_o other_o have_v also_o triangle_n to_o their_o base_n svppose_v that_o abcdef_n be_v a_o prism_n have_v to_o his_o base_a the_o triangle_n abc_n and_o the_o opposite_a side_n unto_o it_o the_o triangle_n def_n then_o i_o say_v that_o the_o prism_n abcdef_n may_v be_v divide_v into_o three_o pyramid_n equal_a the_o one_o to_o the_o other_o and_o have_v triangle_n to_o their_o base_n demonstration_n draw_v these_o right_a line_n bd_o ec_o and_o cd_o and_o forasmuch_o as_o abed_o be_v a_o parallelogram_n and_o his_o diameter_n be_v the_o line_n bd_o therefore_o the_o triangle_n abdella_n be_v equal_a to_o the_o triangle_n edb_n wherefore_o also_o the_o pyramid_n who_o base_a be_v the_o triangle_n abdella_n and_o top_n the_o point_n c_o be_v equal_a to_o the_o pyramid_n who_o base_a be_v the_o triangle_n edb_n &_o top_n the_o point_n c_o by_o the_o 5._o of_o this_o book_n but_o the_o pyramid_n who_o base_a be_v the_o triangle_n edb_n and_o top_n the_o point_n c_o be_v one_o and_o the_o same_o which_o the_o pyramid_n who_o base_a be_v the_o triangle_n ebc_n and_o top_n the_o point_n d_o for_o they_o be_v comprehend_v of_o the_o self_n same_o plain_a superficiece_n namely_o of_o the_o triangle_n bdedec_n dbc_n and_o ebc_n wherefore_o also_o the_o pyramid_n who_o base_a be_v the_o triangle_n abdella_n and_o top_n the_o point_n c_o be_v equal_a to_o the_o pyramid_n who_o base_a be_v the_o triangle_n ebc_n and_o top_n the_o point_n d._n again_o forasmuch_o as_o bcfe_n be_v a_o parallelogram_n and_o the_o diameter_n thereof_o be_v ec_o therefore_o the_o triangle_n ecf_n be_v equal_a to_o the_o triangle_n cbe_n wherefore_o also_o the_o pyramid_n who_o base_a be_v the_o triangle_n ebc_n and_o top_n the_o point_n d_o be_v equal_a to_o the_o pyramid_n who_o base_a be_v the_o triangle_n ecf_n and_o top_n the_o point_n d_o by_o the_o 5._o of_o this_o book_n but_o the_o pyramid_n who_o base_a be_v the_o triangle_n bec_n and_o top_n the_o point_n d_o be_v prove_v to_o be_v equal_a to_o the_o pyramid_n who_o base_a i●_z the_o triangle_n abdella_n and_o top_n the_o point_n c._n wherefore_o also_o the_o pyramid_n who_o base_a be_v the_o triangle_n cef_n and_o top_n the_o point_n d_o be_v equal_a to_o the_o pyramid_n who_o base_a be_v the_o triangle_n abdella_n &_o top_n the_o point_n c._n wherefore_o the_o prism_n abdef_n be_v divide_v into_o three_o equal_a pyramid_n have_v triangle_n to_o their_o base_n and_o forasmuch_o as_o the_o pyramid_n who_o base_a be_v the_o triangle_n abdella_n and_o top_n the_o point_n c_o be_v one_o &_o the_o self_n same_o with_o the_o pyramid_n who_o base_a be_v the_o triangle_n cab_n &_o top_n the_o point_n d_o for_o they_o be_v contain_v under_o the_o self_n same_o plain_a superficiece_n but_o it_o have_v be_v prove_v that_o the_o pyramid_n who_o base_a be_v the_o triangle_n abdella_n and_o top_n the_o point_n c_o be_v the_o three_o pyramid_n of_o the_o prism_n who_o base_a be_v the_o triangle_n abc_n a●d_z the_o opposite_a side_n unto_o it_o the_o triangle_n def_n wherefore_o the_o pyramid_n who_o base_a be_v the_o triangle_n abc_n and_o top_n the_o point_n d_o be_v the_o three_o pyramid_n of_o the_o prism_n who_o base_a be_v the_o triangle_n abc_n and_o opposite_a side_n the_o triangle_n def_n wherefore_o every_o prism_n have_v a_o triangle_n to_o his_o base_a may_v be_v divide_v into_o three_o pyramid_n equal_a the_o one_o to_o the_o other_o have_v also_o triangle_n to_o their_o base_n which_o be_v require_v to_o be_v prove_v ¶_o corollary_n hereby_o it_o be_v manifest_a that_o every_o pyramid_n be_v the_o three_o part_n of_o a_o prism_n have_v one_o and_o the_o same_o base_a with_o it_o and_o also_o be_v under_o the_o self_n same_o altitude_n with_o it_o for_o if_o the_o base_a of_o the_o prism_n be_v any_o other_o rectiline_a figure_n they_o a_o triangle_n that_o also_o may_v be_v divide_v into_o prism_n which_o shall_v have_v triangle_n to_o their_o base_n here_o campane_n and_o flussas_n add_v certain_a corollarye_n first_o corollary_n every_o prism_n be_v treble_a to_o the_o pyramid_n which_o have_v the_o self_n same_o triangle_n to_o his_o base_a that_o the_o prism_n have_v and_o the_o self_n same_o altitude_n as_o it_o be_v manifest_a by_o this_o proposition_n where_o the_o prism_n be_v divide_v into_o three_o equal_a pyramid_n of_o which_o two_o be_v upon_o one_o and_o the_o self_n same_o base_a and_o under_o one_o and_o the_o self_n same_o altitude_n but_o if_o the_o prism_n have_v to_o his_o ●ase_n a_o parallelogram_n and_o if_o the_o pyramid_n have_v to_o his_o base_a the_o half_a of_o the_o same_o parallelogram_n and_o their_o altitude_n be_v equal_a then_o again_o the_o pyramid_n shall_v be_v the_o three_o part_n of_o the_o prism_n for_o it_o be_v manifest_a by_o the_o 40._o of_o the_o cleveth_n that_o prism_n be_v under_o equal_a altitude_n and_o the_o one_o have_v to_o his_o base_a a_o triangle_n and_o the_o other_o a_o parallelogram_n double_a to_o the_o same_o triangle_n be_v equal_a the_o one_o to_o the_o other_o whereof_o follow_v the_o former_a conclusion_n second_o corollary_n if_o there_o be_v many_o prism_n under_o one_o and_o the_o same_o altitude_n and_o have_v triangle_n to_o their_o base_n they_o and_o if_o the_o triangular_a base_n be_v so_o join_v together_o upon_o one_o and_o the_o same_o plain_n that_o they_o compose_v a_o poligonon_n figure_n a_o pyramid_n set_v upon_o that_o base_a be_v a_o poligonon_n figure_n and_o under_o the_o same_o altitude_n be_v the_o three_o part_n of_o that_o solid_a which_o be_v compose_v of_o all_o the_o prism_n add_v together_o for_o forasmuch_o as_o eu●ry_v one_o of_o the_o prism_n which_o have_v to_o his_o base_a a_o triangle_n to_o every_o one_o of_o the_o pyramid_n set_v upon_o the_o same_o base_a the_o altitude_n be_v always_o one_o and_o the_o
fd._n wherefore_o cones_fw-la &_o cylinder_n consist_v upon_o equal_a base_n be_v in_o proportion_n the_o one_o to_o the_o other_o as_o their_o altitude_n which_o be_v require_v to_o be_v demonstrate_v ¶_o the_o 15._o theorem_a the_o 15._o proposition_n in_o equal_a cones_n and_o cylinder_n the_o base_n be_v reciprocal_a to_o their_o altitude_n and_o cones_fw-la and_o cylinder_n who_o base_n be_v reciprocal_a to_o their_o altitude_n be_v equal_a the_o one_o to_o the_o other_o svppose_v that_o these_o cones_fw-la acl_n egn_n or_o these_o cylinder_n axe_n eo_fw-la who_o base_n be_v the_o circle_n abcd_o efgh_o and_o axe_n kl_o and_o mn_v which_o axe_n be_v also_o the_o altitude_n of_o the_o cones_fw-la &_o cylinder_n be_v equal_a the_o one_o to_o the_o other_o cones_n then_o i_o say_v that_o the_o base_n of_o the_o cylinder_n xa_n &_o eo_fw-la be_v reciprokal_n to_o their_o altitude_n that_o be_v that_o as_o the_o base_a abcd_o be_v to_o the_o base_a efgh_o proposition_n so_o the_o altitude_n mn_v to_o the_o altitude_n kl_o for_o the_o altitude_n kl_o be_v either_o equal_a to_o the_o altitude_n mn_a or_o not_o first_o let_v it_o be_v equal_a case_n but_o the_o cylinder_n axe_n be_v equal_a to_o the_o cylinder_n eq_n but_o cones_fw-la and_o cylinder_n consist_v under_o one_o and_o the_o self_n same_o altitude_n be_v in_o proportion_n the_o one_o to_o the_o other_o as_o their_o base_n be_v by_o the_o 11._o of_o the_o twelve_o wherefore_o the_o base_a abcd_o be_v equal_a to_o the_o base_a efgh_o wherefore_o also_o they_o be_v reciprokal_a as_o the_o base_a abcd_o be_v to_o the_o base_a efgh_o so_o be_v the_o altitude_n mn_v to_o the_o altitude_n kl_o but_o now_o suppose_v that_o the_o altitude_n lk_n be_v not_o equal_a to_o the_o altitude_n m._n n_o construction_n but_o let_v the_o altitude_n mn_v be_v great_a and_o by_o the_o 3._o of_o the_o first_o from_o the_o altitude_n mn_v take_v away_o pm_v equal_a to_o the_o altitude_n kl_o so_o that_o let_v the_o line_n pm_n be_v put_v equal_a to_o the_o line_n kl_o and_o by_o the_o point_n p_o let_v there_o be_v extend_v a_o plain_a superficies_n tus_z which_o let_v cut_v the_o cylinder_n eo_fw-la and_o be_v a_o parallel_n to_o the_o two_o opposite_a plain_a super●icieces_n that_o be_v to_o the_o circle_n efgh_o and_o ro._n cylinder_n and_o make_v the_o base_a the_o circle_n efgh_o &_o the_o altitude_n mp_n imagine_v a_o cylinder_n es._n and_o for_o that_o the_o cylinder_n axe_n be_v equal_a to_o the_o cylinder_n eo_fw-la and_o there_o be_v a_o other_o cylinder_n es_fw-ge therefore_o by_o the_o 7._o of_o the_o five_o as_o the_o cylinder_n axe_n be_v to_o the_o cylinder_n es_fw-ge so_o be_v the_o cylinder_n eo_fw-la to_o the_o cylinder_n es._n but_o as_o the_o cylinder_n axe_n be_v to_o the_o cylinder_n es_fw-ge so_o be_v the_o base_a abcd_o to_o the_o base_a efgh_o for_o the_o cylinder_n axe_n and_o es_fw-ge be_v under_o one_o and_o the_o self_n same_o altitude_n and_o as_o the_o cylinder_n eo_fw-la be_v to_o the_o cylinder_n es_fw-ge so_o be_v the_o altitude_n mn_v to_o the_o altitude_n mp_n for_o cylinder_n consist_v upon_o equal_a base_n be_v in_o proportion_n the_o one_o to_o the_o other_o as_o their_o altitude_n wherefore_o as_o the_o base_a abcd_o be_v ●o_o the_o base_a efgh_o so_o be_v the_o altitude_n mn_v to_o the_o altitude_n mp_n but_o the_o altitude_n pm_n be_v equal_a to_o the_o altitude_n kl_o wherefore_o as_o the_o base_a abcd_o be_v to_o the_o base_a efgh_o so_o be_v the_o altitude_n mn_v to_o the_o altitude_n kl_o wherefore_o in_o the_o equal_a cylinder_n axe_n and_o eo_fw-la the_o base_n be_v reciprocal_a to_o their_o altitude_n but_o now_o suppose_v that_o the_o base_n of_o the_o cylinder_n axe_n and_o eo_fw-la be_v reciprokal_n to_o their_o altitude_n that_o be_v as_o the_o base_a abcd_o be_v to_o the_o base_a efgh_o so_o be_v the_o altitude_n mn_v to_o the_o altitude_n kl_o demonstrate_v then_o i_o say_v that_o the_o cylinder_n axe_n be_v equal_a to_o the_o cylinder_n eo_fw-la for_o the_o self_n same_o order_n of_o construction_n remain_v for_o that_o as_o the_o base_a abcd_o be_v to_o the_o base_a efgh_o so_o be_v the_o altitude_n mn_v to_o the_o altitude_n kl_o but_o the_o altitude_n kl_o be_v equal_a to_o the_o altitude_n pm_n wherefore_o as_o the_o base_a abcd_o be_v to_o the_o base_a efgh_o so_o be_v the_o altitude_n mn_v to_o the_o altitude_n pm_n but_o as_o the_o base_a abcd_o be_v to_o the_o base_a efgh_o so_o be_v the_o cylinder_n axe_n to_o the_o cylinder_n es_fw-ge for_o they_o be_v under_o equal_a altitude_n and_o as_o the_o altitude_n mn_o be_v to_o the_o altitude_n pm_n so_o be_v the_o cylinder_n eo_fw-la to_o the_o cylinder_n es_fw-ge by_o the_o 14._o of_o the_o twelve_o wherefore_o also_o as_o the_o cylinder_n axe_n be_v to_o the_o cylinder_n es_fw-ge so_o be_v the_o cylinder_n eo_fw-la to_o the_o cylinder_n es._n wherefore_o the_o cylinder_n axe_n be_v equal_a to_o the_o cylinder_n eo_fw-la by_o the_o 9_o of_o the_o five_o and_o so_o also_o be_v it_o in_o the_o cones_fw-la which_o ha●●_n the_o self_n same_o base_n and_o altitude_n with_o the_o cylinder_n wherefore_o in_o equal_a cones_fw-la and_o cylinder_n the_o base_n be_v reciprocal_a to_o their_o altitude_n etc_n etc_n which_o be_v require_v to_o be_v demonstrate_v a_o corollary_n add_v by_o campane_n and_o flussas_n hitherto_o have_v be_v show_v the_o passion_n and_o propriety_n of_o cones_fw-la and_o cylinder_n who_o altitude_n fall_v perpendicular_o upon_o the_o base_n now_o will_v we_o declare_v that_o cones_fw-la and_o cilinder_n who_o altitude_n fall_v oblique_o upon_o their_o base_n have_v also_o the_o self_n same_o passion_n and_o propriety_n which_o the_o foresay_a cones_fw-la and_o cilinder_n have_v forasmuch_o as_o in_o the_o ten_o of_o this_o book_n it_o be_v say_v that_o every_o cone_n be_v the_o three_o part_n of_o a_o cilind_a have_v one_o and_o the_o self_n same_o base_a &_o one_o &_o the_o self_n same_o altitude_n with_o it_o which_o thing_n be_v demonstrate_v by_o a_o cilind_a give_v who_o base_a be_v cut_v by_o a_o square_n inscribe_v in_o it_o and_o upon_o the_o side_n of_o the_o square_n be_v describe_v isosceles_a triangle_n make_v a_o polygonon_n figure_n and_o again_o upon_o the_o side_n of_o this_o polygonon_n figure_n be_v infinite_o after_o the_o same_o manner_n describe_v other_o isosceles_a triangle_n take_v away_o more_o they_o the_o half_a as_o have_v oftentimes_o be_v declare_v therefore_o it_o be_v manifest_a that_o the_o solid_n set_v upon_o these_o base_n be_v under_o the_o same_o altitude_n that_o the_o cilind_a incline_v be_v and_o be_v also_o include_v in_o the_o same_o cilind_a do_v take_v away_o more_o than_o the_o half_a of_o the_o cilind_a and_o also_o more_o they_o the_o half_a of_o the_o residue_n as_o it_o have_v be_v prove_v in_o erect_a cylinder_n for_o these_o incline_n solid_n be_v under_o equal_a altitude_n and_o upon_o equal_a base_n with_o the_o erect_a solid_n be_v equal_a to_o the_o erect_a solid_n by_o the_o corollary_n of_o the_o _o of_o the_o eleven_o wherefore_o they_o also_o in_o like_a sort_n as_o the_o erect_a take_v away_o more_o than_o the_o half_a if_o therefore_o we_o compare_v the_o incline_v cilind_a to_o a_o cone_n set_v upon_o the_o self_n same_o base_a and_o have_v his_o altitude_n erect_v and_o reason_n by_o a_o argument_n lead_v to_o a_o impossibility_n by_o the_o demonstration_n of_o the_o ten_o of_o this_o book_n we_o may_v prove_v that_o the_o side_v solid_a include_v in_o the_o incline_v cylinder_n be_v great_a than_o the_o triple_a of_o his_o pyramid_n and_o it_o be_v also_o equal_a to_o the_o same_o which_o be_v impossible_a and_o this_o be_v the_o first_o case_n wherein_o it_o be_v prove_v that_o the_o cilind_a not_o be_v equal_a to_o the_o triple_a of_o the_o cone_n be_v not_o great_a than_o the_o triple_a of_o the_o same_o and_o as_o touch_v the_o second_o case_n we_o may_v after_o the_o same_o manner_n conclude_v that_o that_o ●ided_v solid_a contain_v in_o the_o cylinder_n be_v great_a than_o the_o cylinder_n which_o be_v very_o absurd_a wherefore_o if_o the_o cylinder_n be_v neither_o great_a than_o the_o triple_a of_o the_o cone_n nor_o less_o it_o must_v needs_o be_v equal_a to_o the_o same_o the_o demonstration_n of_o these_o incline_v cylinder_n most_v plain_o follow_v the_o demonstration_n of_o the_o erect_a cylinder_n for_o it_o have_v already_o be_v prove_v that_o pyramid_n and_o side_v solid_n which_o be_v also_o call_v general_o prism_n be_v set_v upon_o equal_a base_n and_o under_o one_o and_o the_o self_n same_o altitude_n whether_o the_o altitude_n be_v erect_v or_o incline_v be_v equal_a the_o one_o to_o the_o other_o namely_o be_v in_o proportion_n as_o their_o base_n be_v by_o
the_o 7._o of_o the_o five_o our_o conclusion_n be_v infer_v the_o superficies_n spherical_a of_o the_o segment_n caesar_n to_o be_v to_o the_o superficies_n spherical_a of_o the_o segment_n fgh_o as_o ad_fw-la be_v to_o give_v a_o theorem_a 6._o to_o any_o solid_a sector_n of_o a_o sphere_n that_o upright_o c●●e_n be_v equal_a who_o base_a be_v equal_a to_o the_o connex_v spherical_a superficies_n of_o that_o sector_n and_o heith_n equal_a to_o the_o semidiameter_n of_o the_o same_o sphere_n hereof_o the_o demonstration_n in_o respect_n of_o the_o premise_n and_o the_o common_a argument_n of_o inscription_n and_o circumscription_n of_o figure_n be_v easy_a and_o nevertheless_o if_o your_o own_o write_n will_v not_o help_v you_o sufficient_o you_o may_v take_v help_n at_o archimedes_n hand_n in_o his_o first_o book_n &_o last_o proposition_n of_o the_o sphere_n and_o cylinder_n whether_o if_o you_o have_v recourse_n you_o shal●_n perceive_v how_o your_o theorem_a here_o amend_v the_o common_a translation_n there_o and_o also_o our_o delineation_n give_v more_o s●u●y_a show_n of_o the_o chief_a circumstance_n necessary_a to_o the_o construction_n than_o there_o you_o shall_v find_v of_o the_o sphere_n here_o imagine_v to_o be_v a_o we_o note_v a_o solid_a sector_n by_o the_o letter●_n pqro._n so_o that_o pqr_n do_v signify_v the_o spherical_a superficies_n to_o that_o solid_a sector_n belong_v note_n which_o be_v also_o common_a to_o the_o segment_n of_o the_o same_o sphere_n prq_n and_o therefore_o a_o line_n draw_v from_o the_o top_n of_o that_o segment●_n which_o top_n suppose_v to_o be_v queen_n be_v the_o semidiameter_n of_o the_o circle_n which_o be_v equal_a to_o the_o spherical_a superficies_n of_o the_o say_v solid_a sector_n or_o segment●_n as_o before_o be_v teach_v let_v that_o line_n be_v qp_n by_o q_n draw_v a_o line_n contingent_a which_o let_v be_v sqt._n at_o the_o point_n q_o from_o the_o line_n q_n cut_v a_o line_n equal_a to_o pq_n which_o let_v be_v sq_n and_o unto_o sq_n make_v qt_o equal_a then_o draw_v the_o right_a line_n oso●_n and_o oq_fw-la about_o which_o oq_fw-la as_o a_o axe_n fa●●ened_v if_o you_o imagine_v the_o triangle_n ost_n to_o make_v a_o etc_n half_a circular_a revolution_n you_o shall_v have_v the_o upright_a cone_fw-mi ost_n who_o heith_n be_v oq_fw-la the_o semidiameter_n of_o the_o sphere_n and_o base_a the_o circle_n who_o diameter_n be_v n-ab_n equal_a to_o the_o solid_a sector_n pqro._n a_o theorem_a 7._o to_o any_o segment_n or_o portion_n of_o a_o sphere_n that_o cone_fw-mi i●_z equal_a which_o have_v that_o circle_n to_o his_o base_a which_o be_v the_o b●se_a of_o the_o segment_n and_o heith_n a_o right_a line_n which_o unto_o the_o heith_n of_o the_o segment_n have_v that_o proportion_n which_o the_o semidiameter_n of_o the_o sphere_n together_o with_o the_o heith_n of_o the_o other_o segment_n remay●●●g_o have_v to_o the_o heith_n of_o the_o same_o other_o segment_n remayn●ng_v this_o be_v well_o demonstrate_v by_o archi●●des_n &_o therefore_o need_v no_o invention_n of_o i_o cylindr●_n to_o confirm_v the_o same_o and_o for_o that_o the_o say_a demonstration_n be_v over_o long_o here_o to_o be_v add_v i_o will_v refer_v you_o thither_o for_o the_o demonstration_n and_o here_o supply_v that_o which_o to_o archimedes_n demonstration_n shall_v geve_v light_a and_o to_o your_o far_a speculation_n and_o practice_n shall_v be_v a_o great_a aid_n and_o direction_n suppose_v king_n to_o be_v a_o sphere_n &_o the_o great_a circle_n king_n in_o contain_v let_v be_v abce_n and_o his_o diameter_n be_v &_o centre_n d._n let_v the_o sphere_n king_n be_v cut_v by_o a_o plain_a superficies_n perpendicular_o erect_v upon_o the_o say_v great_a circle_n abce_n let_v the_o section_n be_v the_o circle_n about_o ac_fw-la and_o let_v the_o segment_n of_o the_o sphere_n be_v the_o one_o that_o wherein_o be_v abc_n who_o ●oppe_n be_v b●_n and_o the_o other_o let_v be_v that_o wherein_o be_v aec_o and_o his_o top_n let_v be_v e_o i_o say_v that_o a_o cone_fw-mi which_o have_v his_o base_a the_o circle_n about_o ac_fw-la &_o hold_v a_o line_n which_o to_o bf_o the_o heith_n of_o the_o segment_n who_o top_n be_v b_o have_v that_o proportion_n that_o a_o line_n compo●ed_v of_o de_fw-fr the_o semidiameter_n of_o the_o sphere_n and_o of_o the_o heith_n of_o the_o other_o remain_v segment_n who_o top_n be_v e_o have_v to_o of_o the_o heith_n of_o that_o other_o segment_n remain_v be_v equal_a to_o the_o segment_n of_o the_o sphere_n king_n who_o top_n be_v b._n to_o make_v this_o cone_fw-mi take_v my_o easy_a order_n thus_o frame_v your_o work_n for_o the_o find_n of_o the_o four_o proportional_a line●_z by_o make_v of_o the_o first_o and_o a_o line_n compose_v of_o de_fw-fr and_o of_o the_o second●_n and_o the_o three_o let_v be_v bf_o then_o by_o the_o 12._o of_o the_o six●h_o let_v the_o four_o proportional_a line_n be_v find_v which_o let_v be_v fg●_n upon_o fletcher_n the_o centre_n of_o the_o base_a of_o the_o segment_n who_o top_n be_v b_o erect_v a_o line_n perpendicular_a equal_a to_o fg_o find_v and_o draw_v the_o line_n ga_o and_o gc_o and_o so_o make_v perfect_a the_o cone_n gac_n i_o say_v that_o the_o cone_fw-mi gac_n be_v equal_a to_o the_o segment_n of_o the_o sphere_n king_n who_o top_n be_v b._n in_o like_a manner_n for_o the_o other_o segment_n who_o top_n be_v e_o to_o find_v the_o heith_n due_a for_o a_o cone_fw-mi equal_a to_o it_o by_o the_o order_n of_o the_o theorem_a you_o must_v thus_o frame_v your_o line_n let_v the_o first_o be_v bf_o the_o second_o db_o and_o bf_o compose_v in_o one_o right_a line_n and_o the_o three_o must_v be_v of_o where_o by_o the_o 12._o of_o the_o six_o find_v the_o four_o it_o shall_v be_v the_o heith_n to_o rear_v upon_o the_o base_a the_o circle_n about_o ac_fw-la to_o make_v a_o upright_a cone_fw-mi equal_a to_o the_o segment_n who_o top_n be_v e._n ¶_o logistical_o ¶_o the_o logistical_a find_v 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double_a to_o the_o side_n of_o the_o octohedron_n &_o the_o side_n be_v in_o power_n sequitertia_fw-la to_o the_o perpendiclar_a line_n by_o the_o 12._o of_o this_o book_n wherefore_o the_o diameter_n thereof_o be_v in_o power_n duple_fw-fr superbipartiens_fw-la tertias_fw-la to_o the_o perpendicular_a line_n wherefore_o also_o the_o diameter_n and_o the_o perpendicular_a line_n be_v rational_a and_o commensurable_a by_o the_o 6._o of_o the_o ten_o as_o touch_v a_o icosahedron_n it_o be_v prove_v in_o the_o 16._o of_o this_o book_n that_o the_o side_n thereof_o be_v a_o less_o line_n when_o the_o diameter_n of_o the_o sphere_n be_v rational_a and_o forasmuch_o as_o the_o angle_n of_o the_o inclination_n of_o the_o base_n thereof_o be_v contain_v of_o the_o perpendicular_a line_n of_o the_o triangle_n and_o subtend_v of_o the_o right_a line_n which_o subtend_v the_o angle_n of_o the_o pentagon_n which_o contain_v five_o side_n of_o the_o icosahedron_n and_o unto_o the_o perpendicular_a 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the_o side_n of_o the_o icosahedron_n be_v dg_o and_o let_v the_o centre_n be_v the_o point_n e_o from_o which_o draw_v unto_o those_o s●des_n perpendicular_a line_n ei_o and_o ez_o and_o produce_v the_o line_n ei_o to_o the_o point_n b_o and_o draw_v the_o lin●_n bg_o and_o let_v the_o side_n of_o the_o cube_fw-la contain_v in_o the_o self_n same_o sphere_n be_v gc_o then_o i_o say_v that_o the_o superficies_n of_o the_o dodecahedron_n i●_z to_o the_o superficies_n of_o the_o icosahedron_n as_o the_o line_n ●g_z i●_z to_o the_o li●●_n gd_o for_o forasmuch_o as_o the_o line_n ei_o bein●_n divide_v by_o a_o extreme_a and_o mean_a proportion_n the_o great_a segment_n thereof_o shall_v be_v the_o lin●_n ez_o by_o the_o corollary_n of_o the_o first_o of_o this_o book_n demonstration_n and_o the_o line_n cg_o be_v divide_v by_o a_o extreme_a and_o mean_a proportion_n his_o great_a segment_n be_v the_o line_n agnostus_n by_o the_o corollary_n of_o the_o 17._o of_o the_o thirteen_o wherefore_o the_o right_a line_n ei_o and_o cg_o ●r●_n cut_v proportional_o by_o the_o second_o of_o this_o b●oke_n wh●r●fore_o as_o the_o line_n cg_o be_v to_o the_o line_n agnostus_n so_o be_v the_o line_n ei_o to_o the_o line_n ez_fw-fr wher●fore_o that_o which_o it_o contain_v under_o the_o extreme_n cg_o and_o ez_o be_v squall_n to_o that_o which_o i●_z contayn●d_v under_o the_o mean_n agnostus_n and_o ei._n by_o the_o 16._o of_o the_o six_o but_o as_o that_o which_o i●_z contain_v under_o the_o lin●●_n cg_o and_o ●z_n be_v to_o that_o which_o be_v contain_v under_o the_o line_n dg_o and_o ez_o so_o by_o the_o first_o of_o the_o six_o i●_z the_o lin●_n cg_o to_o the_o line_n dg_o for_o both_o those_o parallelogram_n have_v o●●_n and_o the_o self_n same_o altitude_n namely_o the_o line_n ez_fw-fr wherefore_o as_o that_o which_o be_v contain_v under_o the_o line_n ei_o and_o agnostus_n which_o i●_z prove_v equal_a to_o that_o which_o be_v contain_v under_o the_o line●_z cg_o and_o ez_o be_v to_o that_o which_o be_v contain_v under_o the_o line_n dg_o and_o ez_o so_o be_v the_o line_n cg_o to_o the_o li●●_n dg_o but_o as_o that_o which_o be_v contain_v under_o the_o line_n ei_o and_o agnostus_n be_v to_o that_o which_o be_v contain_v under_o the_o line_n dg_o and_o ez_o so_o by_o the_o corollary_n of_o the_o former_a proposition_n be_v the_o superficies_n of_o the_o dodecahedron_n to_o the_o superficies_n of_o the_o icosahedron_n wherefore_o as_o the_o superficies_n ●●_o the_o dodecahedron_n be_v to_o the_o superficies_n of_o the_o icosahedron_n so_o be_v cg_o the_o side_n of_o the_o cube_fw-la to_o gd_v the_o side_n of_o the_o icosahedron_n the_o superficies_n therefore_o of_o a_o dodecahedron_n be_v to_o the_o superficies●_n etc_n etc_n as_o in_o the_o proposition_n which_o be_v require_v to_o be_v prove_v a_o assumpt_n the_o pentagon_n of_o a_o dodecahedron_n order_n be_v equal_a to_o that_o which_o be_v contain_v under_o the_o perpendicular_a line_n which_o fall_v upon_o the_o base_a of_o the_o triangle_n of_o the_o icosahedron_n and_o five_o six_o part_n of_o the_o side_n of_o the_o cube_fw-la the_o say_v three_o solid_n be_v describe_v in_o one_o and_o the_o self_n same_o sphere_n suppose_v that_o in_o the_o circle_n abeg_n the_o pentagon_n of_o a_o dodecahedron_n be_v a●cig_a and_o let_v two_o side_n thereof_o ab_fw-la and_o agnostus_n be_v subtend_v of_o the_o right_a line_n bg_o and_o let_v the_o triangle_n of_o the_o icosahedron_n inscribe_v in_o the_o self_n same_o sphere_n construction_n by_o the_o 4._o of_o this_o book_n be_v afh_n and_o let_v the_o centre_n of_o the_o circle_n be_v the_o point_n d_o and_o let_v the_o diameter_n be_v ade_n cut_v fh_o the_o side_n of_o the_o triangle_n in_o the_o point_n z_o and_o cut_v the_o line_n bg_o in_o the_o point_n k._n and_o draw_v the_o right_a line_n bd._n and_o from_o the_o right_a line_n kg_v cut_v of_o a_o three_o part_n tg_n by_o the_o 9_o of_o the_o six_o now_o than_o the_o line_n bg_o subtend_v two_o side_n of_o the_o dodecahedron_n shall_v be_v the_o side_n of_o the_o cube_fw-la inscribe_v in_o the_o same_o sphere_n demonstration_n by_o the_o 17._o of_o the_o thirteen_o and_o the_o triangle_n of_o the_o icosahedron_n of_o the_o same_o sphere_n shall_v be_v a●h_a by_o the_o 4._o of_o this_o book_n and_o the_o line_n az_o which_o pass_v by_o the_o centre_n d_o shall_v fall_v perpendicular_o upon_o the_o side_n of_o the_o triangle_n for_o forasmuch_o as_o the_o angle_n gay_a &_o bae_o be_v equal_a by_o the_o 27._o of_o the_o third●_o for_o they_o be_v see_v upon_o equal_a circumference_n therefore_o the_o ●ases_v bk_o and_o kg_n be_v by_o the_o ●_o of_o the_o first_o equal_a wherefore_o the_o line_n bt_n contain_v 5._o six_o part_n of_o the_o line_n bg_o then_o i_o say_v that_o that_o which_o be_v contain_v under_o the_o line_n az_o and_o bt_n be_v equal_a to_o the_o pentagon_n a●c●g_n for_o forasmuch_o as_o the_o line_n ●z_n be_v sesquialter_n to_o the_o line_n ad_fw-la for_o the_o line_n d●_n be_v divide_v into_o two_o equal_a part_n in_o the_o point_n z_o by_o the_o corollary_n of_o the_o ●2●_n of_o the_o thirteen_o likewise_o by_o construction_n the_o line_n kg_n be_v sesquialter_fw-la to_o the_o line_n kt_n therefore_o as_o the_o line_n az_o be_v to_o the_o line_n ad_fw-la so_o be_v the_o line_n kg_v to_o the_o 〈◊〉_d ●t_a wherefore_o that_o which_o be_v contain_v unde●_n the_o 〈◊〉_d az_o and_o kt_n be_v equal_a to_o that_o which_o be_v contain_v under_o the_o mean_n ad_fw-la and_o kg_n by_o the_o 16._o of_o the_o six_o but_o unto_o the_o line_n kg_n be_v the_o line_n ●k_v ●roved_v equal_a wherefore_o that_o which_o be_v contain_v under_o the_o line_n az_o and_o kt_n be_v equal_a to_o that_o which_o be_v contain_v under_o the_o line_n ad_fw-la and_o bk_o but_o that_o which_o be_v contain_v under_o the_o line_n ad_fw-la and_o bk_o be_v by_o the_o 41._o of_o the_o first_o double_a to_o the_o triangle_n abdella_n wherefore_o that_o which_o be_v contain_v under_o the_o line_n az_o and_o kt_n be_v double_a to_o the_o same_o triangle_n abdella_n and_o forasmuch_o as_o the_o pentagon_n abcig_n contayneth●_n 〈…〉_o equal_a ●o_o the_o triangle_n abdella_n and_o that_o which_o be_v contain_v under_o the_o line_n az_o and_o kt_n contain_v two_o such_o triangle_n therefore_o the_o pentagon_n abcig_n be_v duple_fw-fr sesquialter_fw-la to_o the_o rectangle_n parallelogram_n contain_v under_o the_o line_n az_o and_o kt_n and_o 〈…〉_o 1._o of_o the_o six_o that_o which_o be_v contain_v under_o the_o line_n az_o and_o bt_n be_v to_o that_o which_o be_v contain_v under_o the_o line_n az_o and_o kt_n as_o the_o base_a bt_n be_v to_o the_o base_a ●●t●_n therefore_o that_o which_o be_v contain_v under_o the_o line_n az_o
def_n who_o side_n let_v be_v de_fw-fr and_o let_v the_o right_a line_n subtend_v the_o angle_n of_o the_o pentagon_n make_v of_o the_o side_n of_o the_o icosahedron_n be_v the_o line_n ef._n then_o i_o say_v that_o the_o side_n ed_z be_v in_o power_n double_a to_o the_o line_n h_o the_o less_o of_o those_o segment_n forasmuch_o as_o by_o that_o which_o be_v demonstrate_v in_o the_o 15._o of_o this_o book_n demonstration_n it_o be_v manifest_a that_o ed_z the_o side_n of_o the_o icosahedron_n be_v the_o great_a segment_n of_o the_o line_n ef●_n and_o that_o the_o diameter_n df_o contain_v in_o power_n the_o two_o line_n ed_z and_o of_o namely_o the_o whole_a and_o the_o great_a segment_n but_o by_o supposition_n the_o side_n ab_fw-la contain_v in_o power_n the_o two_o line_n c_o &_o h_o join_v together_o in_o the_o self_n same_o proportion_n wherefore_o the_o line_n of_o be_v to_o the_o line_n ed_z as_z the_o line_n c_o be_v to_o the_o line_n h_o by_o the_o ●_o o●_n this_o boke●_n and_o alternally_n by_o the_o 16._o of_o the_o five_o the_o line_n of_o be_v to_o the_o line_n c_o as_o the_o line_n ed_z be_v to_o the_o line_n h._n and_o forasmuch_o as_o the_o line_n df_o contain_v in_o power_n the_o two_o line_n ed_z and_o of_o and_o the_o line_n ab_fw-la contain_v in_o power_n the_o two_o line_n c_o and_o h_o therefore_o the_o square_n of_o the_o line_n of_o and_o ed_z be_v to_o the_o square_n of_o the_o line_n df_o as_o the_o square_n of_o the_o line_n c_o and_o h_o to_o the_o square_a ab_fw-la and_o alternate_o the_o square_n of_o the_o line_n of_o and_o ●d_a be_v to_o the_o square_n of_o the_o line_n c_o and_o h_o as_o the_o square_n of_o the_o line_n df_o be_v to_o the_o square_n of_o the_o line_n ab●_n but_o df_o the_o diameter_n be_v by_o the_o 14._o of_o the_o thirten●h_o i●_z power_n double_a to_o ab_fw-la the_o side_n of_o the_o octohedron_n inscribe_v by_o supposition_n in_o the_o same_o sphere_n wherefore_o the_o square_n of_o the_o line_n of_o and_o ed_z be_v double_a to_o the_o square_n of_o the_o line_n c_o and_o h._n and_o therefore_o one_o square_a of_o the_o line_n ed_z be_v double_a to_o one_o square_a of_o the_o line_n h_o by_o the_o 12._o of_o the_o five_o wherefore_o ed_z the_o side_n of_o the_o icosahedron_n be_v in_o power_n duple_n to_o the_o line_n h_o which_o be_v the_o less_o segment_n if_o therefore_o the_o powe●_n of_o the_o side_n of_o a_o octohedron_n be_v express_v by_o two_o right_a line_n join_v together_o by_o a_o extreme_a and_o mean_a proportion_n the_o side_n of_o the_o icosahedron_n contain_v in_o the_o same_o sphere_n shall_v be_v duple_v to_o the_o less_o segment_n the_o 17._o proposition_n if_o the_o side_n of_o a_o dodecahedron_n and_o the_o right_a line_n of_o who_o the_o say_a side_n be_v the_o less_o segment_n be_v so_o set_v that_o they_o make_v a_o right_a angle_n the_o right_a line_n which_o contain_v in_o power_n half_o the_o line_n subtend_v the_o angle_n be_v the_o side_n of_o a_o octohedron_n contain_v in_o the_o self_n same_o sphere_n svppose_v that_o ab_fw-la be_v the_o side_n of_o a_o dodecahedron_n and_o let_v the_o right_a line_n of_o which_o that_o side_n be_v the_o less_o segment_n be_v agnostus_n namely_o which_o couple_v the_o opposite_a side_n of_o the_o dodecahedron_n by_o the_o 4._o corollary_n of_o the_o 17._o of_o the_o thirteen_o construction_n and_o let_v those_o line_n be_v so_o set_v that_o they_o make_v a_o right_a angle_n at_o the_o point_n a._n and_o draw_v the_o right_a line_n bg_o and_o let_v the_o line_n d_o contain_n in_o power_n half_o the_o line_n bg_o by_o the_o first_o proposition_n add_v by_o flussas_n after_o the_o last_o of_o the_o six_o then_o i_o say_v that_o the_o line_n d_o be_v the_o side_n of_o a_o octohedron_n contain_v in_o the_o same_o sphere_n forasmuch_o as_o the_o line_n agnostus_n make_v the_o great_a segment_n gc_o the_o side_n of_o the_o cube_fw-la contain_v in_o the_o same_o sphere_n by_o the_o same_o 4._o corollary_n of_o the_o 17._o of_o the_o thirteen_o demonstration_n and_o the_o square_n of_o the_o whole_a line_n ag._n and_o of_o the_o less_o segment_n ab_fw-la be_v triple_a to_o the_o square_n of_o the_o great_a segment_n gc_o by_o the_o 4._o of_o the_o thirteen_o moreover_o the_o diameter_n of_o the_o sphere_n be_v in_o power_n triple_a to_o the_o same_o line_n gc_o the_o side_n of_o the_o cube_fw-la by_o the_o 15._o of_o the_o thirteen_o wherefore_o the_o line_n bg_o be_v equal_a to_o the_o 〈◊〉_d for_o it_o contain_v in_o power_n the_o two_o line_n ab_fw-la and_o ag_z by_o the_o 47._o of_o the_o first_o and_o therefore_o it_o contain_v in_o power_n the_o triple_a of_o the_o line_n gc_o but_o the_o side_n of_o the_o octohedron_n contain_v in_o the_o same_o sphere_n be_v in_o power_n triple_a to_o half_a the_o diameter_n of_o the_o sphere_n by_o the_o 14._o of_o the_o thirteen_o and_o by_o supposition_n the_o line_n d_o contai●●●●_n in_o pow●●_n the_o half_a of_o the_o line_n bg_o wherefore_o the_o line_n d_o contain_v in_o power_n the_o half_a of_o the_o same_o diameter_n be_v the_o side_n of_o a_o octohedron_n if_o therefore_o the_o side_n of_o a_o dodecahedron_n and_o the_o right_a line_n of_o who_o the_o say_a side_n be_v the_o less_o segment_n be_v so_o set_v that_o they_o make_v a_o right_a angle_n the_o right_a line_n which_o contain_v in_o power_n half_o the_o line_n subtend_v the_o angle_n be_v the_o side_n of_o a_o oc●●●edron_n contain_v in_o the_o self_n same_o sphere_n which_o be_v require_v to_o be_v prove_v a_o corollary_n unto_o what_o right_a line_n the_o side_n of_o the_o octo●edron_n be_v in_o power_n sesquialter_fw-la unto_o the_o same_o line_n the_o side_n of_o the_o dodecahedron_n inscribe_v in_o the_o same_o sphere_n be_v the_o great_a segment_n for_o the_o side_n of_o the_o dodecahedron_n be_v the_o great_a segment_n of_o the_o segment_n cg_o unto_o which_o d_z the_o side_n of_o the_o octohedron_n be_v in_o power_n sesquialter_n that_o be_v be_v half_a of_o the_o power_n of_o the_o line_n bg_o which_o be_v triple_a unto_o the_o line_n cg_o ¶_o the_o 18._o proposition_n if_o the_o side_n of_o a_o tetrahedron_n contain_v in_o power_n two_o right_a line_n join_v together_o by_o a_o extreme_a and_o mean_a proportion_n the_o side_n of_o a_o icosahedron_n describe_v in_o the_o self_n same_o sphere_n be_v in_o power_n sesquialter_fw-la to_o the_o less_o right_a line_n svppose_v that_o abc_n be_v a_o tetrahedron_n and_o let_v his_o side_n be_v ab_fw-la construction_n who_o power_n let_v be_v divide_v into_o the_o line_n agnostus_n and_o gb_o join_v together_o by_o a_o extreme_a and_o mean_a proportion_n namely_o let_v it_o be_v divide_v into_o agnostus_n the_o whole_a line_n and_o gb_o the_o great_a se●ment_n by_o the_o corollary_n of_o the_o first_o proposition_n add_v by_o flussas_n after_o the_o last_o of_o the_o six_o and_o let_v ed_z be_v the_o side_n of_o the_o icosahedron_n edf_o contain_v in_o the_o self_n same_o sphere_n and_o let_v the_o line_n which_o subtend_v the_o angle_n of_o the_o pentagon_n describe_v of_o the_o side_n of_o the_o icosahedron_n be_v ef._n then_o i_o say_v that_z ed_z the_o side_n of_o the_o icosahedron_n be_v in_o power_n sesquialter_fw-la to_o the_o less_o line_n gb_o demonstration_n forasmuch_o as_o by_o that_o which_o be_v demonstrate_v in_o the_o 15._o of_o this_o book_n the_o side_n ed_z be_v the_o gre●ter_a segment_n of_o the_o line_n of_o which_o subtend_v the_o angle_n of_o the_o pentagon_n but_o as_o the_o whole_a line_n of_o be_v to_o the_o great_a segment_n ed_z so_o be_v the_o same_o gr●●ter_a segment_n to_o the_o less_o by_o the_o 30._o of_o the_o six_o and_o by_o supposition_n agnostus_n be_v the_o whole_a line_n and_o g●_n the_o great_a segment_n wherefore_o as_o of_o be_v to_o ed_z so_o be_v agnostus_n to_o g●_n by_o the_o second_o of_o the_o fourteen_o and_o alternate_o the_o line_n of_o be_v to_o the_o line_n agnostus_n as_o the_o line_n ed_z be_v to_o the_o line_n gb_o and_o forasmuch_o as_o by_o supposition_n the_o line_n ab_fw-la contain_v in_o power_n the_o two_o line_n agnostus_n and_o gb_o therefore_o by_o the_o 4●_o of_o the_o first_o the_o angle_n agb_n be_v a_o right_a angle_n but_o the_o angle_n def_n be_v a_o right_a angle_n by_o that_o which_o be_v demonstrate_v in_o the_o 15._o of_o this_o book_n wherefore_o the_o triangle_n ag●_n and_o feed_v be_v equiangle_n by_o the_o ●_o of_o the_o six_o wherefore_o their_o side_n be_v proportional_a namely_o as_o the_o line_n ed_z be_v to_o the_o line_n gb_o so_o be_v the_o line_n fd_o to_o the_o line_n ab_fw-la by_o the_o 4._o of_o the_o six_o but_o by_o that_o which_o have_v before_o
overthrow_v and_o overwhelm_v the_o whole_a world_n he_o be_v utter_o rude_a and_o ignorant_a in_o the_o greek_a tongue_n so_o that_o certain_o he_o never_o read_v euclid_n in_o the_o greek_a nor_o of_o like_a translate_v out_o of_o the_o greek_a but_o have_v it_o translate_v out_o of_o the_o arabike_a tongue_n the_o arabian_n be_v man_n of_o great_a study_n and_o industry_n and_o common_o great_a philosopher_n notable_a physician_n and_o in_o mathematical_a art_n most_o expert_a so_o that_o all_o kind_n of_o good_a learning_n flourish_v and_o reign_v amongst_o they_o in_o a_o manner_n only_o these_o man_n turn_v whatsoever_o good_a author_n be_v in_o the_o greek_a tongue_n of_o what_o art_n and_o knowledge_n so_o ever_o it_o be_v into_o the_o arabike_a tongue_n and_o from_o thence_o be_v many_o of_o they_o turn_v into_o the_o latin_a and_o by_o that_o mean_v many_o greek_a author_n come_v to_o the_o hand_n of_o the_o latin_n and_o not_o from_o the_o first_o fountain_n the_o greek_a tongue_n wherein_o they_o be_v first_o write_v as_o appear_v by_o many_o word_n of_o the_o arabike_a tongue_n yet_o remain_v in_o such_o book_n as_o be_v zenith_n nadir_n helmuayn_fw-mi helmuariphe_n and_o infinite_a such_o other_o which_o arabian_n also_o in_o translate_n such_o greek_a work_n be_v accustom_v to_o add_v as_o they_o think_v good_a &_o for_o the_o full_a understanding_n of_o the_o author_n many_o thing_n as_o be_v to_o be_v see_v in_o diverse_a author_n as_o namely_o in_o theodosius_n de_fw-la sphera_fw-la where_o you_o see_v in_o the_o old_a translation_n which_o be_v undoubteldy_a out_o of_o the_o arabike_a many_o proposition_n almost_o every_o three_o or_o four_o leaf_n some_o such_o copy_n of_o euclid_n most_o likely_a do_v campanus_n follow_v wherein_o he_o find_v those_o proposition_n which_o he_o have_v more_o &_o above_o those_o which_o be_v find_v in_o the_o greek_a set_v out_o by_o hypsicles_n and_o that_o not_o only_o in_o this_o 15._o book_n but_o also_o 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and_o those_o equal_a angle_n be_v contain_v under_o equal_a side_n namely_o under_o the_o half_n of_o the_o side_n of_o the_o pyramid_n wherefore_o the_o triangle_n tkl_n tli_n tie_v tek_v zkl_n zli_n zib_n zek_n be_v equilater_n and_o they_o limitate_v and_o contain_v the_o solid_a tklezi_n wherefore_o the_o solid_a tklezi_n be_v a_o octohedron_n by_o the_o 23._o definition_n of_o the_o eleven_o and_o the_o angle_n of_o the_o same_o octohedron_n do_v touch_v the_o side_n of_o the_o pyramid_n abcd_o in_o the_o point_n e_o z_o i_o t_o edward_n l._n wherefore_o the_o octohedron_n be_v inscribe_v in_o the_o pyramid_n by_o the_o 1._o definition_n of_o this_o book_n wherefore_o in_o the_o trilater_n equilater_n pyramid_n give_v be_v inscribe_v a_o octohedron_n which_o be_v require_v to_o be_v do_v a_o corollary_n add_v by_o flussas_n hereby_o it_o be_v manifest_a that_o a_o pyramid_n be_v cut_v into_o two_o
right_a lin●s_n now_o then_o multiply_v the_o 20._o triangle_n into_o the_o side_n of_o one_o of_o the_o triangle_n and_o so_o shall_v there_o be_v produce_v 6●_o ●he_z half_a of_o which_o be_v 30._o and_o so_o many_o side_n have_v a_o icosahedron_n and_o in_o like_a sort_n in_o a_o dodecahedron_n forasmuch_o as_o 12._o pentagon_n make_v a_o dodecahedron_n and_o every_o pentagon_n contain_v ●_o right_a lines●_n multiply_v ●●_o into_o 12._o and_o there_o shall_v be_v produce_v 60._o the_o half_a of_o which_o be_v 30._o and_o so_o many_o be_v the_o side_n of_o a_o dodecahedron_n and_o the_o reason_n why_o we_o take_v the_o half_a i●_z for_o that_o every_o side_n whether_o it_o be_v of_o a_o triangle_n or_o of_o a_o pentagon_n or_o of_o a_o square_a as_o in_o a_o cube_fw-la ●s_v take_v twice_o and_o by_o the_o same_o reason_n may_v you_o find_v out_o how_o many_o side_n be_v in_o a_o cube_fw-la and_o in_o a_o pyramid_n and_o in_o a_o octohedron_n but_o now_o again_o if_o you_o will_v find_v out_o the_o number_n of_o the_o angle_n of_o every_o one_o of_o the_o solid_a figure_n when_o you_o have_v do_v the_o same_o multiplication_n that_o you_o do_v before_o divide_v the_o same_o side_n by_o the_o number_n of_o the_o plain_a superficiece_n which_o comprehend_v one_o of_o the_o angle_n of_o the_o solid_n as_o for_o example_n forasmuch_o as_o 5._o triangle_n contain_v the_o solid_a angle_n of_o a_o icosahedron_n divide_v 60._o by_o 5._o and_o there_o will_v come_v forth_o 12._o and_o so_o many_o solid_a angle_n have_v a_o icosahedron_n in_o a_o dodecahedron_n forasmuch_o as_o three_o pentagon_n comprehend_v a_o angle_n divide_v 60._o by_o 3._o and_o there_o will_v come_v forth_o 20_o and_o so_o many_o be_v the_o angle_n of_o a_o dodecahedron_n and_o by_o the_o same_o reason_n may_v you_o find_v out_o how_o many_o angle_n be_v in_o each_o of_o the_o rest_n of_o the_o solid_a figure_n book_n if_o it_o be_v require_v to_o be_v know_v how_o one_o of_o the_o plain_n of_o 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centre_n right_a line_n and_o they_o shall_v contain_v likewise_o the_o inclination_n of_o the_o plain_n of_o the_o icosahedron_n in_o a_o dodecahedron_n take_v one_o of_o the_o pentagon_n and_o draw_v likewise_o the_o line_n which_o subtend_v one_o of_o the_o angle_n of_o the_o pentagon_n and_o make_v the_o centre_n the_o end_n of_o that_o line_n and_o the_o space_n the_o perpendicular_a line_n draw_v from_o the_o section_n into_o two_o equal_a part_n of_o that_o line_n to_o the_o side_n of_o the_o pentagon_n which_o be_v parallel_n unto_o it_o describe_v circumference_n and_o from_o the_o point_n of_o the_o intersection_n of_o the_o circumference_n draw_v unto_o the_o centre_n right_a line_n and_o they_o shall_v also_o contain_v the_o inclination_n of_o the_o plain_n of_o the_o dodecahedron_n thus_o do_v this_o most_o singular_a learned_a man_n reason_n think_v the_o demonstration_n in_o every_o one_o of_o they_o to_o be_v plain_a and_o clear_a but_o to_o make_v the_o demonstration_n of_o they_o manifest_a i_o think_v it_o good_a to_o declare_v and_o make_v open_a his_o wordes●_n and_o first_o in_o a_o t●trahedron●_n the_o end_n of_o the_o fivetenth_fw-mi book_n of_o euclides_n element_n after_o 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d ¶_o the_o 6._o proposition_n the_o 6._o problem_n in_o a_o octohedron_n give_v to_o inscribe_v a_o trilater_n equilater_n pyramid_n svppose_v tha●_z the_o octohedron_n where●●_n the_o tetrahedron_n be_v require_v to_o be_v ins●ri●●●_n be_v abgdei_n take_v 〈…〉_o base_n of_o the_o octo●●dron_n that_o be_v construction_n 〈…〉_o close_o in_o the_o lowe●●_n triangle_n bgd_v namely_o ae●_n head_n igd_v and_o let_v the_o four_o be_v aib_n which_o be_v opposite_a to_o the_o low_a triangle_n before_o put_v namely_o to_o egg_v and_o take_v the_o centre_n of_o those_o four_o base_n which_o let_v be_v the_o point_n h_o c_o n_o ●_o and_o upon_o the_o triangle_n hcn_n erect_v a_o pyramid_n hcnl_n now_o forasmuch_o as_o these_o two_o base_n of_o the_o 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line_n fk_o by_o the_o 2._o of_o the_o six_o and_o also_o to_o the_o side_n of_o the_o octohedron_n namely_o to_o e●_n and_o ig_n by_o the_o 9_o of_o the_o eleven_o wherefore_o as_o the_o line_n of_o be_v to_o the_o line_n ah_o so_o be_v the_o line_n fk_o to_o the_o line_n hl_o by_o the_o 4._o of_o the_o six_o for_o the_o triangle_n afk_v and_o ahl_n be_v like_o by_o th●_z corollary_n of_o the_o 2._o of_o the_o six_o but_o the_o line_n of_o be_v in_o sesquialter_fw-la proportion_n to_o the_o line_n ah_o for_o the_o side_n eglantine_n make_v hf_o the_o half_a of_o the_o right_a line_n ah_o by_o the_o corollary_n of_o the_o 12._o of_o the_o thirteen_o wherefore_o fk_n or_o give_v the_o side_n of_o the_o octohedron_n be_v sesquialter_fw-la to_o the_o righ●line_n hl._n and_o by_o the_o same_o reason_n may_v we_o prove_v that_o the_o side_n of_o the_o octohedron_n be_v sesquialter_fw-la to_o the_o rest_n of_o the_o right_a line_n which_o make_v the_o pyramid_n hnci_n namely_o to_o the_o right_a line●●_n n_o nc_n ci_o ln_o and_o change_z wherefore_o those_o right_a line_n be_v equal_a and_o therefore_o the_o triangle●_n which_o be_v describe_v of_o they_o namely_o the_o triangle_n hcn_n hnl_n ncl_n and_o chl._n which_o make_v the_o pyramid_n hncl_n be_v equal_a and_o equilater_n and_o forasmuch_o as_o the_o angle_n of_o the_o same_o pyramid_n namely_o the_o angle_n h_o c_o n_o l_o do_v end_n in_o the_o centre_n of_o the_o base_n of_o the_o octohedron_n therefore_o it_o be_v inscribe_v ●o_o the_o same_o octohedron_n by_o the_o first_o definition_n of_o this_o book_n wherefore_o in_o a_o octohedron_n ●even_v be_v inscribe_v a_o trilate_a equila●●●●●●amis●_n which_o be_v require_v to_o ●e_a don●_n a_o corollary_n the_o base_n of_o a_o pyramid_n inscribe_v in_o a_o octohedron_n be_v parallel_n
the_o square_a of_o the_o line_n a_o have_v not_o unto_o the_o square_n of_o the_o line_n b_o the_o same_o proportion_n that_o a_o square_a number_n have_v to_o a_o square_a number_n then_o i_o say_v that_o the_o line_n a_o and_o b_o be_v incommensurable_a in_o length_n for_o if_o the_o line_n a_o and_o b_o be_v commensurable_a in_o length_n than_o the_o square_a of_o the_o line_n a_o shall_v have_v unto_o the_o square_n of_o the_o line_n b_o the_o same_o proportion_n that_o a_o square_a number_n have_v to_o a_o square_a number_n by_o the_o first_o part_n of_o this_o proposition_n but_o by_o supposition_n it_o have_v not_o wherefore_o the_o line_n a_o and_o b_o be_v not_o commensurable_a in_o length_n proposition_n wherefore_o they_o be_v incomensurable_a in_o length_n wherefore_o square_n make_v of_o right_a line_n commensura_fw-la in_o length_n have_v that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n and_o square_n which_o have_v that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o squa●e_a number_n shall_v also_o have_v the_o side_n commensurable_a in_o length_n but_o square_n describe_v of_o right_a line_n incommensurable_a in_o length_n have_v not_o that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n and_o square_n which_o have_v not_o that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n have_v not_o also_o their_o side_n commensurable_a in_o length_n which_o be_v all_o that_o be_v require_v to_o be_v prove_v ¶_o corollary_n hereby_o it_o be_v manifest_a that_o right_a line_n commensurable_a in_o length_n be_v also_o ever_o commensurable_a in_o power_n but_o right_a line_n commensurable_a in_o power_n be_v not_o always_o commensurable_a in_o length_n corollary_n and_o right_a line_n incommensurable_a in_o length_n be_v not_o always_o incommensurable_a in_o power_n but_o right_a line_n incommensurable_a in_o power_n be_v ever_o also_o incommensurable_a in_o length_n for_o forasmuch_o as_o square_n make_v of_o right_a line_n commensurable_a in_o length_n have_v that_o proportion_n the_o one_o to_o the_o other_o corollary_n that_o a_o square_a number_n have_v to_o a_o square_a number_n by_o the_o first_o part_n of_o this_o proposition_n but_o magnitude_n which_o have_v that_o proportion_n the_o one_o to_o the_o other_o that_o number_n simple_o have_v to_o number_n be_v by_o the_o six_o of_o the_o ten_o commensurable_a wherefore_o right_a line_n commensurable_a in_o length_n be_v commensurable_a not_o only_o in_o length_n but_o also_o in_o power_n part_n again_o forasmuch_o as_o there_o be_v certain_a square_n which_o have_v not_o that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n but_o yet_o have_v that_o proportion_n the_o one_o to_o the_o other_o which_o number_n simple_o have_v to_o number_v their_o side_n in_o deed_n be_v in_o power_n commensurable_a for_o that_o they_o describe_v square_n which_o have_v that_o proportion_n which_o number_n simple_o have_v to_o number_n which_o square_n be_v therefore_o commensurable_a by_o the_o 6._o of_o this_o book_n but_o the_o say_v side_n be_v incommensurable_a in_o length_n by_o the_o latter_a part_n of_o this_o proposition_n wher●fore_o it_o be_v true_a that_o line_n commensurable_a in_o power_n be_v not_o straight_o way_n commensurable_a in_o length_n also_o p●rt_n and_o by_o the_o sel●e_a same_o reason_n be_v prove_v also_o that_o three_o part_n of_o the_o corollary_n that_o line_n incommensurable_a in_o length_n be_v not_o always_o incommensurable_a in_o power_n for_o they_o may_v be_v incommensurable_a in_o length_n but_o yet_o commensurable_a in_o power_n as_o in_o those_o square_n which_o be_v in_o proportion_n the_o one_o to_o the_o other_o as_o number_n be_v to_o number_n but_o not_o as_o a_o square_a number_n be_v to_o a_o square_a number_n part_n but_o right_a line_n incommensurable_a in_o power_n be_v always_o also_o incommensurable_a in_o length_n for_o i●_z they_o be_v commensurable_a in_o length_n they_o shall_v also_o be_v commensurable_a in_o power_n by_o the_o first_o part_n of_o this_o corollary_n but_o they_o be_v suppose_v to_o be_v incommensurable_a in_o length_n which_o be_v absurd_a wherefore_o right_a line_n incommensurable_a in_o power_n be_v ever_o incommensurable_a in_o lengthy_a for_o the_o better_a understanding_n of_o this_o proposition_n and_o the_o other_o follow_v i_o have_v here_o add_v certain_a annotation_n take_v out_o of_o montaureus_n montau●●us_fw-la and_o first_o as_o touch_v the_o signification_n o●_n word_n and_o term_n herein_o use_v wh●ch_a ar●_n such_o that_o unless_o they_o be_v well_o mark_v and_o poise_v the_o matter_n will_v be_v obscure_a and_o hard_a and_o in_o a_o manner_n inexplicable_a first_o this_o you_o must_v note_v that_o line_n to_o be_v commensurable_a in_o length_n and_o line_n to_o be_v in_o proportion_n the_o one_o to_o the_o other_o as_o number_n be_v to_o number_n be_v all_o one_o so_o that_o whatsoever_o line_n be_v commensurable_a in_o length_n be_v also_o in_o proportion_n the_o one_o to_o the_o other_o as_o number_n be_v to_o number_v and_o converse_o what_o so_o ever_o line_n be_v in_o proportion_n the_o one_o to_o the_o other_o as_o number_n be_v to_o number_n be_v also_o commensurable_a in_o length_n as_o it_o be_v manifest_a by_o the_o 5_o and_o 6_o of_o this_o book_n likewise_o line_n to_o be_v incommensurable_a in_o length_n and_o not_o to_o be_v in_o proportion_n the_o one_o to_o the_o other_o as_o number_n be_v to_o number_n be_v all_o one_o as_o it_o be_v manifest_a by_o the_o 7._o and_o 8._o of_o this_o book_n wherefore_o that_o which_o be_v say_v in_o this_o theorem_a aught_o to_o be_v understand_v of_o line_n commensurable_a in_o length_n and_o incommensurable_a in_o length_n this_o moreover_o be_v to_o be_v note_v that_o it_o be_v not_o all_o one_o numbers_z to_o be_v square_a number_n and_o to_o be_v in_o proportion_n the_o one_o to_o the_o other_o as_o a_o square_a number_n be_v to_o a_o square_a number_n for_o although_o square_a number_n be_v in_o proportion_n the_o one_o to_o the_o other_o as_o a_o square_a number_n be_v to_o a_o square_a number_n yet_o be_v not_o all_o those_o number_n which_o be_v in_o proportion_n the_o one_o to_o the_o other_o as_o a_o square_a number_n be_v to_o a_o square_a number_n square_a number_n for_o they_o may_v be_v like_o superficial_a number_n and_o yet_o not_o square_a number_n which_o yet_o be_v in_o proportion_n the_o one_o to_o the_o other_o as_o a_o square_a number_n be_v to_o a_o square_a number_n although_o all_o square_a number_n be_v like_o superficial_a number_n for_o between_o two_o square_a number_n there_o fall_v one_o mean_a proportional_a number_n by_o the_o 11._o of_o the_o eight_o but_o if_o between_o two_o number_n there_o fall_v one_o mean_v proportional_a number_n those_o two_o number_n be_v like_o superficial_a number_n by_o the_o 20._o of_o the_o eight_o so_o also_o if_o two_o number_n be_v in_o proportion_n the_o one_o to_o the_o other_o as_o a_o square_a number_n be_v to_o a_o square_a number_n they_o shall_v be_v like_o superficial_a number_n by_o the_o first_o corollary_n add_v after_o the_o last_o proposition_n of_o the_o eight_o book_n and_o now_o to_o know_v whether_o two_o superficial_a number_n give_v be_v like_o superficial_a number_n or_o no_o no._n it_o be_v thus_o find_v out_o first_o if_o between_o the_o two_o number_n give_v there_o fall_v no_o mean_a proportional_a then_o be_v not_o these_o two_o number_n like_o superficial_a number_n by_o the_o 18._o of_o the_o eight_o but_o if_o there_o do_v fall_v between_o they_o a_o mean_v proportional_a then_o be_v they_o like_v super●iciall_a number_n by_o the_o 20._o of_o the_o eight_o moreover_o two_o like_o superficial_a number_n multiply_v the_o one_o into_o the_o other_o do_v produce_v a_o square_a number_n by_o the_o firs●_o of_o the_o nine_o wherefore_o if_o they_o do_v not_o produce_v a_o square_a number_n then_o be_v they_o not_o like_o superficial_a number_n and_o if_o the_o one_o be_v multiply_v into_o the_o other_o they_o produce_v a_o square_a number_n then_o be_v they_o like_v superficial_a by_o the_o 2._o of_o the_o nine_o moreover_o if_o the_o say_v two_o superficial_a number_n be_v in_o superperticular_a or_o superbipartient_fw-fr proportion_n then_o be_v they_o not_o like_o superficial_a number_n for_o if_o they_o shall_v be_v like_a then_o shall_v there_o be_v a_o mean_a proportional_a between_o they_o by_o the_o 20._o of_o the_o eight_o but_o that_o be_v contrary_a to_o the_o corollary_n of_o the_o 20._o of_o the_o eight_o and_o the_o easy_o to_o conceive_v the_o demonstration_n follow_v take_v this_o example_n of_o that_o which_o we_o have_v say_v ¶_o
a_o assumpt_n forasmuch_o as_o in_o the_o eight_o book_n in_o the_o 26._o proposition_n it_o be_v prove_v that_o like_o plain_a number_n have_v that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n and_o likewise_o in_o the_o 24._o of_o the_o same_o book_n it_o be_v prove_v that_o if_o two_o number_n have_v that_o proportion_n the_o one_o to_o the_o other_o eight_o that_o a_o square_a number_n have_v to_o a_o square_a number_n those_o number_n be_v like_o plain_a number_n hereby_o it_o be_v manifest_a that_o unlike_o plain_a number_n that_o be_v who_o side_n be_v not_o proportional_a have_v not_o that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n for_o if_o they_o have_v than_o shall_v they_o be_v like_o plain_a number_n which_o be_v contrary_a to_o the_o supposition_n wherefore_o unlike_o plain_a number_n have_v not_o that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n and_o therefore_o square_n which_o have_v that_o proportion_n the_o one_o to_o the_o other_o that_o unlike_o plain_a number_n have_v shall_v have_v their_o side_n incommensurable_a in_o length_n by_o the_o last_o part_n of_o the_o former_a proposition_n for_o that_o those_o square_n have_v not_o that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n ¶_o the_o 8._o theorem_a the_o 10._o proposition_n if_o four_o magnitude_n be_v proportional_a and_o if_o the_o first_o be_v commensurable_a unto_o the_o second_o the_o three_o also_o shall_v be_v commensurable_a unto_o the_o four_o and_o if_o the_o first_o be_v incommensurable_a unto_o the_o second_o the_o three_o shall_v also_o be_v incommensurable_a unto_o the_o four_o svppose_v that_o these_o four_o magnitude_n a_o b_o c_o d_o be_v proportional_a as_o a_o be_v to_o b_o so_o let_v c_o be_v to_o d_o and_o let_v a_o be_v commensurable_a unto_o b._n then_o i_o say_v that_o c_z be_v also_o commensurable_a unto_o d._n part_n for_o forasmuch_o as_o a_o be_v commensurable_a unto_o b_o it_o have_v by_o the_o five_o of_o the_o ten_o that_o proportion_n that_o number_n have_v to_o number_v but_o as_o a_o be_v to_o b_o so_o be_v c_o to_o d._n wherefore_o c_z also_o have_v unto_o d_z that_o proportion_n that_o number_n have_v to_o number_v wherefore_o c_o be_v commensurable_a unto_o d_z by_o the_o 6._o of_o the_o ten_o but_o now_o suppose_v that_o the_o magnitude_n a_o be_v incommensurable_a unto_o the_o magnitude_n b._n part●_n then_o i_o say_v that_o the_o magnitude_n c_o also_o be_v incommensurable_a unto_o the_o magnitude_n d._n for_o forasmuch_o as_o a_o be_v incommensurable_a unto_o b_o therefore_o by_o the_o 7._o of_o this_o book_n a_o have_v not_o unto_o b_o such_o proportion_n as_o number_n have_v to_o number_v but_o as_o a_o be_v to_o b_o so_o be_v c_o to_o d._n wherefore_o c_o have_v not_o unto_o d_z such_o proportion_n as_o number_n have_v to_o number_v wherefore_o by_o the_o 8._o of_o the_o ten_o c_o be_v incommensurable_a unto_o d._n if_o therefore_o there_o be_v four_o magnitude_n proportional_a and_o if_o the_o first_o be_v commensurable_a unto_o the_o second_o the_o three_o also_o shall_v be_v commensurable_a unto_o the_o four_o and_o if_o the_o first_o be_v incommensurable_a unto_o the_o second_o the_o three_o shall_v also_o be_v incommensurable_a unto_o the_o four_o which_o be_v require_v to_o be_v prove_v ¶_o a_o corollary_n add_v by_o montaureus_n if_o there_o be_v four_o line_n proportional_a and_o if_o the_o two_o first_o or_o the_o two_o last_o be_v commensurable_a in_o power_n only_o the_o other_o two_o also_o shall_v be_v commensurable_a in_o power_n only_o corollary_n this_o be_v prove_v by_o the_o 22._o of_o the_o six_o and_o by_o this_o ten_o proposition_n and_o this_o corollary_n euclid_n use_v in_o the_o 27._o and_o 28._o proposition_n of_o this_o book_n and_o in_o other_o proposition_n also_o ¶_o the_o 3._o problem_n the_o 11._o proposition_n unto_o a_o right_a line_n first_o set_v and_o give_v which_o be_v call_v a_o rational_a line_n to_o find_v out_o two_o right_a line_n incommensurable_a the_o one_o in_o length_n only_o and_o the_o other_o in_o length_n and_o also_o in_o power_n svppose_v that_o the_o right_a line_n first_o set_v and_o give_v which_o be_v call_v a_o rational_a line_n of_o purpose_n be_v a._n it_o be_v require_v unto_o the_o say_a line_n a_o to_o find_v out_o two_o right_a line_n incommensurable_a the_o one_o in_o length_n only_o the_o other_o both_o in_o length_n and_o in_o power_n give_v take_v by_o that_o which_o be_v add_v after_o the_o 9_o proposition_n of_o this_o book_n two_o number_n b_o and_o c_o not_o have_v that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n that_o be_v let_v they_o not_o be_v like_o plain_a number_n for_o like_o plain_a number_n by_o the_o 26._o of_o the_o eight_o have_v that_o proportion_n the_o one_o to_o the_o other_o that_o a_o square_a number_n have_v to_o a_o square_a number_n and_o as_o the_o number_n b_o be_v to_o the_o number_n c_o so_fw-mi let_v the_o square_n of_o the_o line_n a_o be_v unto_o the_o square_n of_o a_o other_o line_n namely_o of_o d_z how_o to_o do_v this_o be_v teach_v in_o the_o assumpt_n put_v before_o the_o 6._o proposition_n of_o this_o book_n wherefore_o the_o square_a of_o the_o line_n a_o be_v unto_o the_o square_n of_o the_o line_n d_o commensurable_a by_o the_o six_o of_o the_o ten_o and_o forasmuch_o as_o the_o number_n b_o have_v not_o unto_o the_o number_n c_o that_o proportion_n that_o a_o square_a number_n have_v to_o a_o square_a number_n therefore_o the_o square_a of_o the_o line_n a_o have_v not_o unto_o the_o square_n of_o the_o line_n d_z that_o proportion_n that_o a_o square_a number_n have_v to_o a_o number_n wherefore_o by_o the_o 9_o of_o the_o ten_o the_o line_n a_o be_v unto_o the_o line_n d_o incommensurable_a in_o length_n only_o and_o so_o be_v find_v out_o the_o first_o line_n namely_o d_z incommensurable_a in_o length_n only_o to_o the_o line_n give_v a._n give_v again_o take_v by_o the_o 13._o of_o the_o six_o the_o mean_a proportional_a between_o the_o line_n a_o and_o d_o and_o let_v the_o same_o be_v e._n wherefore_o as_o the_o line_n a_o be_v to_o the_o line_n d_o so_o be_v the_o square_a of_o the_o line_n a_o to_o the_o square_n of_o the_o line_n e_o by_o the_o corollary_n of_o the_o 20._o of_o the_o six_o but_o the_o line_n a_o be_v unto_o the_o line_n d_o incommensurable_a in_o length_n wherefore_o also_o the_o square_a of_o the_o line_n a_o be_v unto_o the_o square_n of_o the_o line_n e_o incommensurable_a by_o the_o second_o part_n of_o the_o former_a proposition_n now_o forasmuch_o as_o the_o square_n of_o the_o line_n a_o be_v incommensurable_a to_o the_o square_n of_o the_o line_n e_o it_o follow_v by_o the_o definition_n of_o incommensurable_a line_n that_o the_o line_n a_o be_v incommensurable_a in_o power_n to_o the_o line_n e._n wherefore_o unto_o the_o right_a line_n give_v and_o first_o set_v a_o which_o be_v a_o rational_a line_n and_o which_o be_v suppose_v to_o have_v such_o division_n and_o so_o many_o part_n as_o you_o listen_v to_o conceive_v in_o mind_n as_o in_o this_o example_n 11_z whereunto_o as_o be_v declare_v in_o the_o 5._o definition_n of_o this_o book_n may_v be_v compare_v infinite_a other_o line_n either_o commensurable_a or_o incommensurable_a be_v find_v out_o the_o line_n d_o incommensurable_a in_o length_n only_o wherefore_o the_o line_n d_o be_v rational_a by_o the_o six_o definition_n of_o this_o book_n for_o that_o it_o be_v incommensurable_a in_o length_n only_o to_o the_o line_n a_o which_o be_v the_o first_o line_n set_v and_o be_v by_o supposition_n rational_a there_o be_v also_o find_v out_o the_o line_n e_o which_o be_v unto_o the_o same_o line_n a_o incommensurable_a not_o only_o in_o length_n but_o also_o in_o power_n which_o line_n e_o compare_v to_o the_o rational_a line_n a_o be_v by_o the_o definition_n irrational_a for_o euclid_n always_o call_v those_o line_n irrational_a which_o be_v incommensurable_a both_o in_o length_n and_o in_o power_n to_o the_o line_n first_o set_v and_o by_o supposition_n rational_a ¶_o the_o 9_o theorem_a the_o 12._o proposition_n magnitude_n commensurable_a to_o one_o and_o the_o self_n same_o magnitude_n be_v also_o commensurable_a the_o one_o to_o the_o other_o svppose_v that_o either_o of_o these_o magnitude_n a_o and_o b_o be_v commensurable_a unto_o the_o magnitude_n c_o then_o i_o say_v that_o the_o magnitude_n a_o be_v commensurable_a unto_o the_o magnitude_n b._n construction_n for_o forasmuch_o as_o the_o
the_o circle_n a_o construction_n have_v to_o the_o circle_n b._n as_o the_o diameter_n of_o the_o circle_n a_o be_v to_o the_o diameter_n of_o the_o circle_n b_o so_fw-mi let_v the_o line_n c_o be_v to_o a_o four_o line_n by_o the_o 12._o of_o the_o 〈…〉_o line_n be_v d._n and_o by_o the_o 11._o of_o the_o six_o let_v a_o third_o line_n proportional_a be_v find_v to_o the_o line_n c_o &_o d_o which_o let_v be_v e●_n i_o say_v now_o that_o the_o line_n c_o have_v too_o the_o line_n e_o that_o proportion_n which_o the_o circle_n a_o have_v to_o the_o circle_n b._n for_o by_o construction_n the_o line●_z c_o d_o and_o e_o demonstration_n be_v proportional_a therefore_o the_o square_n of_o c●_n be_v to_o the_o square_n of_o d_o as_z c_z be_v to_o e_o by_o the_o corollary_n of_o the_o 10._o of_o the_o six_o but_o by_o construction_n as_o the_o diameter_n of_o the_o circle_n a_o be_v to_o the_o diameter_n of_o the_o circle_n b_o so_o be_v c_o to_o d_z wherefore_o as_o the_o square_n of_o the_o diameter_n of_o the_o circle_n a_o be_v to_o the_o square_n of_o the_o diameter_n of_o the_o circle_n b_o so_o be_v the_o square_a of_o the_o line_n c_o to_o the_o square_n of_o the_o line_n d_o by_o the_o 22._o of_o the_o six_o but_o as_o the_o square_n of_o the_o diameter_n of_o a_o the_o circle_n be_v to_o the_o square_n of_o the_o diameter_n of_o the_o circle_n d_o so_o be_v the_o circle_n a_o to_o the_o circle_n b_o by_o the_o second_o of_o the_o twelve_o wherefore_o by_o 11._o of_o the_o five_o as_o the_o circle_n a_o be_v to_o the_o circle_n b_o so_o be_v the_o square_a of_o the_o line_n c_o to_o the_o square_n of_o the_o li●e_z d._n but_o it_o be_v prove_v that_o ●s_v the_o square_a of_o the_o line_n c_o be_v to_o the_o square_n of_o the_o line_n d_o so_o be_v the_o line_n c_o to_o the_o line_n e._n wherefore_o by_o the_o 11._o of_o the_o five_o as_o the_o circle_n a_o be_v to_o the_o circle_n b_o so_o be_v the_o line_n c_o to_o the_o line_n e._n two_o circle_n be_v give_v therefore_o and_o a_o right_a line_n we_o have_v find_v a_o right_a line_n to_o which_o the_o right_a line_n give_v have_v that_o proportion_n which_o the_o one_o circle_n have_v to_o the_o other_o which_o ought_v to_o be_v do_v note_n the_o difference_n between_o this_o problem_n and_o that_o next_o before_o be_v this_o there_o although_o we_o have_v two_o circle_n give_v second_o and_o two_o line_n be_v find_v in_o that_o proportion_n the_o one_o to_o the_o other_o in_o which_o the_o give_v circle_n be_v and_o here_o likewise_o be_v two_o circle_n give_v and_o two_o line●_z also_o be_v have_v in_o the_o same_o proportion_n that_o the_o give_v circle_n be_v yet_o there_o we_o take_v at_o pleasure_n the_o first_o of_o the_o two_o line_n whereunto_o we_o frame_v the_o second_o proportional_o to_o the_o circle_n give_v but_o here_o the_o first_o of_o the_o two_o line_n be_v assign_v point_a a●d_z determine_v to_o we_o and_o not_o our_o choice_n to_o be_v have_v therein_o as_o be_v in_o the_o former_a problem_n a_o problem_n 3._o a_o circle_n be_v give_v to_o find_v a_o other_o circle_n to_o which_o the_o give_v c●rcle_n be_v in_o any_o proportion_n give_v in_fw-ge two_o right_a line_n suppose_v the_o circle_n a●c_n give_v and_o therefore_o his_o semidiameter_n be_v give_v whereby_o his_o diameter_n also_o be_v give_v which_o diameter_n let_v be_v ac_fw-la let_v the_o proportion_n give_v be_v that_o which_o be_v between_o ●_o f_o two_o right_a line_n i_o say_v a_o circle_n be_v to_o be_v find_v unto_o which_o a●c_n have_v that_o proportion_n that_o ●_o have_v to_o ●_o as_o ●_o be_v to_o ●_o construction_n so_o let_v ac_fw-la the_o diameter_n be_v to_o a_o other_o right_a line_n by_o the_o 12._o of_o the_o six_o which_o line_n suppose_v to_o be_v 11._o between_o ac_fw-la and_o ●●_o find_v a_o middle_n proportional_a line_n by_o the_o 13._o of_o the_o six_o which_o let_v be_v ln_o by_o the_o 10._o of_o the_o first_o divide_v ●n_n into_o two_o equal_a payte_n and_o let_v that_o be_v do_v in_o the_o point_n ●_o now_o upon_o ●●_o o_o being_n make_v the_o centre_n describe_v a_o circle_n which_o let_v be_v ●n●_n demonstration_n i_o say_v that_o abc_n be_v to_o lmn_o as_o ●_o be_v to_o f._n for_o see_v that_o ac_fw-la ln_o and_o h_o be_v three_o right_a line_n in_o continual_a proportion_n by_o construction_n therefore_o by_o the_o corollary_n of_o the_o 20._o of_o the_o six_o as_o ac_fw-la be_v to_o h_o so_o be_v the_o square_a of_o a●_z to_o the_o square_n of_o ln_o but_o ac_fw-la be_v to_o h_o as_z ●_o be_v to_o ●_o by_o construction_n wherefore_o the_o square_a of_o ac_fw-la be_v to_o the_o square_n of_o ln_o as_o e_o be_v fletcher_n but_o as_o the_o square_n of_o the_o diameter_n ac_fw-la be_v to_o the_o square_n of_o the_o diameter_n ln_o so_o be_v the_o circle_n abc_n to_o the_o circle_n ●mn_v by_o this_o 2._o of_o the_o twelve_o wherefore_o by_o the_o 11._o of_o the_o five_o the_o circle_n abc_n be_v to_o the_o circle_n lmn_o as_o ●_o be_v to_o f._n a_o circle_n be_v give_v therefore_o a_o other_o circle_n be_v find_v to_o which_o the_o give_v circle_n be_v in_o any_o proportion_n give_v between_o two_o right_a line_n which_o ought_v to_o be_v do_v a_o problem_n 4._o two_o circle_n be_v give_v to_o find_v one_o circle_n equal_a to_o they_o both_o suppose_v the_o two_o circle_n give_v have_v their_o diameter_n a●_z &_o cd_o i_o say_v that_o a_o circle_n must_v be_v ●ound_v equal_a to_o the_o two_o circle_n who_o diameter_n be_v a●_z and_o cd_o unto_o the_o line_n a●_z construction_n at_o the_o point_n a_o erect_v a_o perpendicular_a line_n a●_z from_o which_o sufficient_o produce_v cut_v a_o line_n equal_a to_o cd_o which_o let_v be_v af._n by_o the_o first_o petition_n draw_v from_o fletcher_n to_o ●_o a_o right_n line_n so_o be_v fa●_n make_v a_o triangle_n rectangle_n i_o say_v now_o that_o a_o circle_n who_o diameter_n be_v f●_n be_v equal_a to_o the_o two_o circle_n who_o diameter_n be_v a●_z and_o ●d_a demonstration_n for_o by_o the_o 47._o of_o the_o first_o the_o square_a of_o f●_n be_v equal_a to_o the_o square_n of_o a●_z &_o af._n which_o of_o be_v by_o construction_n equal_a to_o cd●_n wherefore_o the_o square_a of_o f●_n be_v equal_a to_o the_o square_n of_o ab_fw-la and_o cd_o but_o circle_n be_v one_o to_o a_o other_o as_o the_o square_n of_o their_o diameter_n be_v one_o to_o the_o other_o by_o this_o second_o of_o the_o twelve_o therefore_o the_o circle_n who_o diameter_n be_v ●●_o be_v equal_a to_o the_o circle_n who_o diameter_n be_v a●_z and_o cd_o therefore_o two_o circle_n be_v give_v we_o have_v find_v a_o circle_n equal_a to_o they_o both_o which_o be_v require_v to_o be_v do_v a_o corollary_n 1._o hereby_o it_o be_v make_v evident_a that_o in_o all_o triangle_n rectangle_n the_o circle_n semicircle_n quadrant_n o●_n any_o other_o portion_n of_o circle_n describe_v upon_o the_o subtendent_fw-la line_n be_v equal_a to_o the_o two_o circle_n semicircle_n quadrant_n or_o any_o two_o other_o like_a portion_n of_o circle_n describe_v on_o the_o two_o line_n comprehend_v the_o right_a angle_n like_v to_o like_v be_v compare_v for_o like_a part_n have_v that_o proportion_n between_o themselves_o that_o their_o whole_a magnitude_n have_v of_o which_o they_o be_v like_o part_n by_o the_o 15._o of_o the_o five_o but_o of_o the_o whole_a circle_n in_o the_o former_a problem_n it_o be_v evident_a and_o therefore_o in_o the_o forname_v like_o portion_n of_o circle_n it_o be_v a_o true_a consequent_a a_o corollary_n 2._o by_o the_o former_a problem_n it_o be_v also_o manifest_a unto_o circle_n three_o four_o five_o or_o to_o how_o many_o so_o ever_o one_o will_v geve_v one_o circle_n may_v be_v give_v equal_a for_o if_o first_o to_o any_o two_o by_o the_o former_a problem_n you_o find_v one_o equal_a and_o then_o unto_o your_o find_a circle_n and_o the_o three_o of_o the_o give_v circle_n as_o two_o give_v circle_n find_v one_o other_o circle_n equal_a and_o then_o to_o that_o second_o find_v circle_n and_o to_o the_o four_o of_o the_o first_o give_v circles●_n as_o two_o circle_n one_o new_a circle_n be_v find_v equal_a and_o so_o proceed_v till_o you_o have_v once_o couple_v orderly_a every_o one_o of_o your_o propound_a circle_n except_o the_o first_o and_o second_o already_o do_v with_o the_o new_a circle_n thus_o find_v for_o so_o the_o last_o find_v circle_n be_v equal_a to_o all_o the_o first_o give_v circle_n if_o you_o doubt_v or_o sufficient_o understand_v i_o not_o help_v yourself_o by_o the_o discourse_n and_o demonstration_n of_o the_o