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betwixt_o they_o it_o be_v all_o one_o as_o if_o he_o refuse_v to_o be_v teach_v but_o if_o he_o understand_v nothing_o then_o certain_o the_o definition_n be_v faulty_a for_o the_o nature_n of_o a_o definition_n consist_v in_o this_o that_o it_o exhibit_v a_o clear_a idea_n of_o the_o thing_n define_v and_o principle_n be_v either_o know_v by_o themselves_o or_o else_o they_o be_v not_o principle_n four_o that_o in_o philosophy_n definition_n be_v before_o define_v name_n for_o in_o teach_v philosophy_n the_o first_o beginning_n be_v from_o definition_n and_o all_o progression_n in_o the_o same_o till_o we_o come_v to_o the_o knowledge_n of_o the_o thing_n compound_v be_v compositive_a see_v therefore_o definition_n be_v the_o explication_n of_o a_o compound_v name_n by_o resolution_n and_o the_o progression_n be_v from_o the_o part_n to_o the_o compound_n definition_n must_v be_v understand_v before_o compound_v name_n nay_o when_o
same_o chapter_n i_o have_v show_v that_o whatsoever_o be_v at_o rest_n will_v always_o be_v at_o rest_n unless_o there_o be_v some_o other_o body_n beside_o it_o which_o by_o get_v into_o its_o place_n suffer_v it_o no_o long_o to_o remain_v at_o rest._n and_o that_o whatsoever_o be_v move_v will_v always_o be_v move_v unless_o there_o be_v some_o other_o body_n beside_o it_o which_o hinder_v its_o motion_n ten_o in_o the_o 9_o chapter_n and_o 7_o article_n i_o have_v demonstrate_v that_o when_o any_o body_n be_v move_v which_o be_v former_o at_o rest_n the_o immediate_a efficient_a cause_n of_o that_o motion_n be_v in_o some_o other_o move_v and_o contiguous_a body_n eleven_o i_o have_v show_v in_o the_o same_o place_n that_o whatsoever_o be_v move_v will_v always_o be_v move_v in_o the_o same_o way_n and_o with_o the_o same_o swiftness_n if_o it_o be_v not_o hinder_v by_o some_o other_o move_v and_o contiguous_a body_n 2_o to_o which_o principle_n i_o shall_v here_o add_v these_o that_o follow_v first_o i_o define_v endeavour_n to_o be_v motion_n make_v in_o less_o space_n and_o time_n then_o can_v be_v give_v that_o be_v less_o than_o can_v be_v determine_v or_o assign_v by_o exposition_n or_o number_n that_o be_v motion_n make_v through_o the_o length_n of_o a_o point_n and_o in_o a_o instant_a or_o point_n of_o time_n for_o the_o explayn_v of_o which_o definition_n it_o must_v be_v remember_v that_o by_o a_o point_n be_v not_o to_o be_v understand_v that_o which_o have_v no_o quantity_n or_o which_o can_v by_o any_o mean_n be_v divide_v for_o there_o be_v no_o such_o thing_n in_o nature_n but_o that_o who_o quantity_n be_v not_o at_o all_o consider_v that_o be_v whereof_o neither_o quantity_n nor_o any_o part_n be_v compute_v in_o demonstration_n so_o that_o a_o point_n be_v not_o to_o be_v take_v for_o a_o indivisible_a but_o for_o a_o undivided_a thing_n as_o also_o a_o instant_a be_v to_o be_v take_v for_o a_o undivided_a and_o not_o for_o a_o indivisible_a time_n in_o like_a manner_n endeavour_n be_v to_o be_v conceive_v as_o motion_n but_o so_o as_o that_o neither_o the_o quantity_n of_o the_o time_n in_o which_o nor_o of_o the_o line_n in_o which_o it_o be_v make_v may_v in_o demonstration_n be_v at_o all_o bring_v into_o comparison_n with_o the_o quantity_n of_o that_o time_n or_o of_o that_o line_n of_o which_o it_o be_v a_o part_n and_o yet_o as_o a_o point_n may_v be_v compare_v with_o a_o point_n so_o one_o endeavour_n may_v be_v compare_v with_o another_o endeavour_n and_o one_o may_v be_v find_v to_o be_v great_a or_o less_o than_o another_o for_o if_o the_o vertical_a point_n of_o two_o angle_n be_v compare_v they_o will_v be_v equal_a or_o unequal_a in_o the_o same_o proportion_n which_o the_o angle_n themselves_o have_v to_o one_o another_o or_o if_o a_o straight_a line_n cut_v many_o circumference_n of_o concentric_a circle_n the_o inequality_n of_o the_o point_n of_o intersection_n will_v be_v in_o the_o same_o proportion_n which_o the_o perimeter_n have_v to_o one_o another_o and_o in_o the_o same_o manner_n if_o two_o motion_n begin_v and_o end_n both_o together_o their_o endeavour_n will_v be_v equal_a or_o unequal_a according_a to_o the_o proportion_n of_o their_o velocity_n as_o we_o see_v a_o bullet_n of_o lead_n descend_v with_o great_a endeavour_n than_o a_o ball_n of_o wool_n second_o i_o define_v impetus_fw-la or_o quickness_n of_o motion_n to_o be_v the_o swiftness_n or_o velocity_n of_o the_o body_n move_v but_o consider_v in_o the_o several_a point_n of_o that_o time_n in_o which_o it_o be_v move_v in_o which_o sense_v impetus_fw-la be_v nothing_o else_o but_o the_o quantity_n or_o velocity_n of_o endeavour_n but_o consider_v with_o the_o whole_a time_n it_o be_v the_o whole_a velocity_n of_o the_o body_n move_v take_v together_o throughout_o all_o the_o time_n and_o equal_a to_o the_o product_n of_o a_o line_n represent_v the_o time_n multiply_v into_o a_o line_n represent_v the_o arithmetical_o mean_v impetus_fw-la or_o quickness_n which_o arithmetical_a mean_n what_o it_o be_v be_v define_v in_o the_o 29_o article_n of_o the_o 13_o chapter_n and_o because_o in_o equal_a time_n the_o way_n that_o be_v pass_v be_v as_o the_o velocity_n and_o the_o impetus_fw-la be_v the_o velocity_n they_o go_v withal_o reckon_v in_o all_o the_o several_a point_n of_o the_o time_n it_o follow_v that_o during_o any_o time_n whatsoever_o howsoever_o the_o impetus_fw-la be_v increase_v or_o decrease_v the_o length_n of_o the_o way_n pass_v over_o shall_v be_v increase_v or_o decrease_v in_o the_o same_o proportion_n and_o the_o same_o line_n shall_v represent_v both_o the_o way_n of_o the_o body_n move_v and_o the_o several_a impetus_fw-la or_o degree_n of_o swiftness_n wherewith_o the_o way_n be_v pass_v over_o and_o if_o the_o body_n move_v be_v not_o a_o point_n but_o a_o straight_a line_n move_v so_o as_o that_o every_o point_n thereof_o make_v a_o several_a straight_a line_n the_o plain_a describe_v by_o its_o motion_n whether_o uniform_a accelerate_a or_o retard_v shall_v be_v great_a or_o less_o the_o time_n be_v the_o same_o in_o the_o same_o proportion_n with_o that_o of_o the_o impetus_fw-la reckon_v in_o one_o motion_n to_o the_o impetus_fw-la reckon_v in_o the_o other_o for_o the_o reason_n be_v the_o same_o in_o parallellogram_n and_o their_o side_n for_o the_o same_o cause_n also_o if_o the_o body_n move_v be_v a_o plain_a the_o solid_a describe_v shall_v be_v still_o great_a or_o less_o in_o the_o proportion_n of_o the_o several_a impetus_fw-la or_o quickness_n reckon_v through_o one_o line_n to_o the_o several_a impetus_fw-la reckon_v through_o another_o this_o understand_v let_v abcd_v in_o the_o first_o figure_n of_o the_o 17_o chapter_n be_v a_o parallelogram_n in_o which_o suppose_v the_o side_n ab_fw-la to_o be_v move_v parallel_o to_o the_o opposite_a side_n cd_o decrease_v all_o the_o way_n till_o it_o vanish_v in_o the_o point_n c_o and_o so_o describe_v the_o figure_n abefc_n the_o point_n b_o as_o ab_fw-la decrease_v will_v therefore_o describe_v the_o line_n befc_n and_o suppose_v the_o time_n of_o this_o motion_n design_v by_o the_o line_n cd_o and_o in_o the_o same_o time_n cd_o suppose_v the_o side_n ac_fw-la to_o be_v move_v parallelly_n and_o uniform_o to_o bd._n from_o the_o point_n o_o take_v at_o adventure_n in_o the_o line_n cd_o draw_v or_o parallel_v to_o bd_o cut_v the_o line_n befc_n in_o e_o and_o the_o side_n ab_fw-la in_o r._n and_o again_o from_o the_o point_n qui_fw-fr take_v also_o at_o adventure_n in_o the_o line_n cd_o draw_v q_n parallel_v to_o bd_o cut_v the_o line_n befc_n in_o f_o and_o the_o side_n ab_fw-la in_o saint_n and_o draw_v eglantine_n and_o fh_n parallel_n to_o cd_o cut_v ac_fw-la in_o g_z and_o h._n last_o suppose_v the_o same_o construction_n do_v in_o all_o the_o point_n possible_a of_o the_o line_n befc_n i_o saâ—_n that_o as_o the_o proportion_n of_o the_o swiftness_n wherewith_o qf_n oe_o db_n and_o all_o the_o rest_n supopse_v to_o be_v draw_v parallel_n to_o db_n and_o terminate_v in_o the_o line_n befc_n be_v to_o the_o proportion_n of_o their_o several_a time_n design_v by_o the_o several_a parallel_n hf_n ge_n ab_fw-la and_o all_o the_o rest_n suppose_v to_o be_v draw_v parallel_n to_o the_o line_n of_o time_n cd_o and_o terminate_v in_o the_o line_n befc_n the_o aggregate_v to_o the_o aggregate_v so_o be_v the_o area_n or_o plain_a dbefc_n to_o the_o area_n or_o plain_a acfeb_n for_o as_o ab_fw-la decrease_v continual_o by_o the_o line_n befc_n vanish_v in_o the_o time_n cd_o into_o the_o point_n c_o so_o in_o the_o same_o time_n the_o line_n dc_o continual_o decrease_v vanish_v by_o the_o same_o line_n cfeb_n into_o the_o point_n b_o and_o the_o point_n d_o describe_v in_o that_o decrease_a motion_n the_o line_n db_n equal_a to_o the_o line_n ac_fw-la describe_v by_o the_o point_n a_o in_o the_o decrease_a motion_n of_o a_o &_o b_o &_o their_o swiftness_n be_v therefore_o equal_a again_o because_o in_o the_o time_n ge_n the_o point_n o_o describe_v the_o line_n oe_v and_o in_o the_o same_o time_n the_o point_n r_o describe_v the_o line_n re_fw-mi the_o line_n oe_n shall_v be_v to_o the_o line_n re_fw-mi as_o the_o swiftness_n wherewith_o oe_n be_v describe_v to_o the_o swiftness_n wherewith_o re_n be_v describe_v in_o like_a manner_n because_o in_o the_o same_o time_n hf_n the_o point_n qui_fw-fr describe_v the_o line_n qf_n and_o the_o point_n s_o the_o line_n sf_n it_o shall_v be_v as_o the_o swiftness_n by_o which_o qf_n be_v describe_v to_o the_o swiftness_n by_o which_o sf_n be_v describe_v so_o the_o line_n itself_o qf_o to_o the_o line_n itself_o sf_n and_o so_o in_o all_o the_o line_n that_o can_v possible_o be_v
which_o it_o be_v inscribe_v so_o that_o the_o compliment_n of_o the_o spiral_n that_o be_v that_o space_n in_o the_o circle_n which_o be_v without_o the_o spiral_n line_n be_v double_a to_o the_o space_n within_o the_o spiral_n line_n in_o the_o same_o manner_n if_o there_o be_v take_v a_o mean_a proportional_a every_o where_o between_o the_o semidiameter_n of_o the_o circle_n which_o contain_v the_o spiral_n and_o that_o part_n of_o the_o semidiameter_n which_o be_v within_o the_o same_o there_o will_v be_v make_v another_o figure_n which_o will_v be_v half_a the_o circle_n and_o to_o conclude_v this_o rule_n serve_v for_o all_o such_o space_n as_o may_v be_v describe_v by_o a_o line_n or_o superficies_n decrease_v either_o in_o magnitude_n or_o power_n so_o that_o if_o the_o proportion_n in_o which_o they_o decrease_v be_v commensurable_a to_o the_o proportion_n of_o the_o time_n in_o which_o they_o decrease_v the_o magnitude_n of_o the_o figure_n they_o describe_v will_v be_v know_v 12_o the_o truth_n of_o that_o proposition_n which_o i_o demonstrate_v in_o the_o second_o article_n which_o be_v the_o foundation_n of_o all_o that_o have_v be_v say_v concern_v deficient_a figure_n may_v be_v derive_v from_o the_o element_n of_o philosophy_n as_o have_v iâ—â—_n original_n in_o this_o that_o all_o equality_n and_o inequality_n between_o two_o effect_n that_o be_v all_o proportion_n proceed_v from_o and_o be_v determine_v by_o the_o equal_a and_o unequal_a cause_n of_o those_o effect_n or_o from_o the_o proportion_n which_o the_o cause_n concur_v to_o one_o effect_n have_v to_o the_o cause_n which_o concur_v to_o the_o produce_v of_o the_o other_o effect_n and_o that_o therefore_o the_o proportion_n of_o quantity_n be_v the_o same_o with_o the_o proportion_n of_o their_o cause_n see_v therefore_o two_o deficient_a figure_n of_o which_o one_o be_v the_o compliment_n of_o the_o other_o be_v make_v one_o by_o motion_n decrease_v in_o a_o certain_a time_n and_o proportion_n the_o other_o by_o the_o loss_n of_o motion_n in_o the_o same_o time_n the_o cause_n which_o make_v and_o determine_v the_o quantity_n of_o both_o the_o figure_n so_o that_o they_o can_v be_v no_o other_o than_o they_o be_v differ_v only_o in_o this_o that_o the_o proportion_n by_o which_o the_o quantity_n which_o generate_v the_o figure_n proceed_v in_o describe_v of_o the_o same_o that_o be_v the_o proportion_n of_o the_o remainder_n of_o all_o the_o time_n and_o altitude_n may_v be_v other_o proportion_n then_o those_o by_o which_o the_o same_o generate_a quantity_n decrease_v in_o make_v the_o compliment_n of_o that_o figure_n that_o be_v the_o proportion_n of_o the_o quantity_n which_o generate_v the_o figure_n continual_o diminish_v wherefore_o as_o the_o proportion_n of_o the_o quantity_n in_o which_o motion_n be_v lose_v be_v to_o that_o of_o the_o decrease_a quantity_n by_o which_o the_o deficient_a figure_n be_v generate_v so_o will_v the_o defect_n or_o compliment_n be_v to_o the_o figure_n itself_o which_o be_v generate_v 13_o there_o be_v also_o other_o quantity_n which_o be_v determinable_a from_o the_o knowledge_n of_o their_o cause_n namely_o from_o the_o comparison_n of_o the_o motion_n by_o which_o they_o be_v make_v and_o that_o more_o easy_o then_o from_o the_o common_a element_n of_o geometry_n for_o example_n that_o the_o superficies_n of_o any_o portion_n of_o a_o sphere_n be_v equal_a to_o that_o circle_n who_o radius_fw-la be_v a_o straight_a line_n draw_v from_o the_o pole_n of_o the_o portion_n to_o the_o circumference_n of_o its_o base_a i_o may_v demonstrate_v in_o this_o manner_n let_v b_o a_o c_o in_o the_o 7_o figure_n be_v a_o portion_n of_o a_o sphere_n who_o axis_n be_v a_o e_o &_o who_o base_a be_v b_o c_o &_o let_v a_o b_o be_v the_o straight_a line_n draw_v from_o the_o pole_n a_o to_o the_o base_a in_o b_o and_o let_v a_o d_o equal_a to_o a_o b_o touch_v the_o great_a circle_n b_o a_o c_o in_o the_o pole_n a._n it_o be_v to_o be_v prove_v that_o the_o circle_n make_v by_o the_o radius_fw-la a_o d_o be_v equal_a to_o the_o superficies_n of_o the_o portion_n b_o a_o c._n let_v the_o plain_n a_o e_o b_o d_o be_v understand_v to_o make_v a_o revolution_n about_o the_o axis_n a_o e_o &_o it_o be_v manifest_a that_o by_o the_o straight_a line_n a_o d_o a_o circle_n will_v be_v describe_v and_o by_o the_o arch_n a_o b_o the_o superficies_n of_o a_o portion_n of_o a_o sphere_n and_o last_o by_o the_o subtense_n a_o b_o the_o superficies_n of_o a_o right_a cone_n now_o see_v both_o the_o straight_a line_n a_o b_o and_o the_o arch_n a_o b_o make_v one_o and_o the_o same_o revolution_n and_o both_o of_o they_o have_v the_o same_o extreme_a point_n a_o and_o b_o the_o cause_n why_o the_o the_o spherical_a superficies_n which_o be_v make_v by_o the_o arch_n be_v great_a than_o the_o conical_a superficies_n which_o be_v make_v by_o the_o subtense_n be_v that_o a_o b_o the_o arch_n be_v great_a than_o a_o b_o the_o subtense_n and_o the_o cause_n why_o it_o be_v great_a consist_v in_o this_o that_o although_o they_o be_v both_o draw_v from_o a_o to_o b_o yet_o the_o subtense_n be_v draw_v straight_o but_o the_o arch_n angular_o namely_o according_a to_o that_o angle_n which_o the_o arch_n make_v with_o the_o subtense_n which_o angle_n be_v equal_a to_o the_o angle_n d_o a_o b_o for_o a_o angle_n of_o contingence_n add_v nothing_o to_o a_o angle_n of_o a_o segment_n as_o have_v be_v show_v in_o the_o 14_o chapter_n at_o the_o 16_o article_n wherefore_o the_o magnitude_n of_o the_o angle_n d_o a_o b_o be_v the_o cause_n why_o the_o superficies_n of_o the_o portion_n describe_v by_o the_o arch_n a_o b_o be_v great_a than_o the_o superficies_n of_o the_o right_a cone_n describe_v by_o the_o subtense_n a_o b._n again_o the_o cause_n why_o the_o circle_n describe_v by_o the_o tangent_fw-la a_o d_o be_v great_a than_o the_o superficies_n of_o the_o right_a cone_n describe_v by_o the_o subtense_n a_o b_o notwitstand_v that_o the_o tangent_fw-la and_o the_o subtense_n be_v equal_a and_o both_o move_v round_o in_o the_o same_o time_n be_v this_o that_o a_o d_o stand_v at_o right_a angle_n to_o the_o axis_n but_o a_o b_o oblique_o which_o obliquity_n consist_v in_o the_o same_o angle_n d_o a_o b._n see_v therefore_o the_o quantity_n of_o the_o angle_n d_o a_o b_o be_v that_o which_o make_v the_o excess_n both_o of_o the_o superficies_n of_o the_o portion_n and_o of_o the_o circle_n make_v by_o the_o radius_fw-la a_o d_o above_o the_o superficies_n of_o the_o right_a cone_n describe_v by_o the_o subtense_n a_o b_o it_o follow_v that_o both_o the_o superficies_n of_o the_o portion_n and_o that_o of_o the_o circle_n do_v equal_o exceed_v the_o superficies_n of_o the_o cone_n wherefore_o the_o circle_n make_v by_o a_o d_o or_o a_o b_o and_o the_o spherical_a superficies_n make_v by_o the_o arch_n a_o b_o be_v equal_a to_o one_o another_o which_o be_v to_o be_v prove_v â—4_n if_o these_o deficient_a figure_n which_o i_o have_v describe_v in_o a_o 〈◊〉_d be_v capable_a of_o exact_a description_n than_o any_o number_n of_o mean_a proportional_n may_v be_v find_v out_o between_o two_o straight_a line_n give_v for_o example_n in_o the_o parallelogram_n a_o b_o c_o d_o in_o the_o 8_o figure_n let_v the_o threesided_n figure_n of_o two_o mean_n be_v describe_v which_o many_o call_v a_o cubical_a parabola_fw-la and_o let_v r_o and_o s_o be_v two_o give_v straight_o line_n between_o which_o if_o it_o be_v require_v to_o find_v two_o mean_a proportional_n it_o may_v be_v do_v thus_o let_v it_o be_v as_o r_o to_o saint_n so_o b_o c_z to_z b_o f_o and_o let_v f_o e_z be_v draw_v parallel_n to_o b_o a_o and_o cut_v the_o crooked_a line_n in_o e_z then_z through_z e_z let_v g_o h_n be_v draw_v parallel_n and_o equal_a to_o the_o straight_a line_n a_o d_o and_o cut_v the_o diagonal_a b_o d_o in_o i_o for_o thus_o we_o have_v g_o i_o the_o great_a of_o two_o mean_n between_o g_o h_n and_o g_o e_o as_o appear_v by_o the_o description_n of_o the_o figure_n in_o the_o four_o article_n wherefore_o if_o it_o be_v as_o g_z h_z to_z g_z ay_o so_o r_o to_o another_o line_n t_o that_o t_n will_v be_v the_o great_a of_o two_o mean_n between_o r_o and_o s._n and_o therefore_o if_o it_o be_v again_o as_o r_o to_o t_n so_o t_n to_o another_o line_n x_o that_o will_v be_v do_v which_o be_v require_v in_o the_o same_o manner_n four_o mean_a proportional_n may_v be_v find_v out_o by_o the_o description_n of_o a_o threesided_n figure_n of_o four_o mean_n and_o so_o any_o other_o number_n of_o mean_n etc._n etc._n chap._n xviii_o of_o the_o equation_n of_o straight_a line_n with_o the_o
the_o suppose_a hardness_n and_o therefore_o the_o other_o must_v needs_o be_v namely_o that_o the_o body_n come_v near_o to_o a._n wherefore_o the_o body_n at_o i_o have_v great_a endeavour_n towards_o the_o centre_n a_o when_o its_o hard_a side_n be_v next_o it_o then_o when_o it_o be_v avert_v from_o it_o but_o the_o body_n in_o i_o while_o it_o be_v move_v in_o the_o circumference_n of_o the_o circle_n ib_n have_v sometime_o one_o side_n sometime_o another_o turn_v towards_o the_o centre_n and_o therefore_o it_o be_v sometime_o near_o sometime_o further_o off_o from_o the_o centre_n a._n wherefore_o the_o body_n at_o i_o be_v not_o carry_v in_o the_o circumference_n of_o a_o perfect_a circle_n which_o be_v to_o be_v demonstrate_v chap._n xxii_o of_o other_o variety_n of_o motion_n 1_o endeavour_n and_o pressure_n how_o they_o differ_v 2_o two_o kind_n of_o medium_n in_o which_o body_n be_v move_v 3_o propagation_n of_o motion_n what_o it_o be_v 4_o what_o motion_n body_n have_v when_o they_o press_v one_o another_o 5_o fluid_a body_n when_o they_o be_v press_v together_o penetrate_v one_o another_o 6_o when_o one_o body_n press_v another_o and_o do_v not_o penetrate_v it_o the_o action_n of_o the_o press_a body_n be_v perpendicular_a to_o the_o superficies_n of_o the_o body_n press_v 7_o when_o a_o hard_a body_n press_v another_o body_n penetrate_v the_o same_o it_o do_v not_o penetrate_v it_o perpendicular_o unless_o it_o fall_v perpendicular_o upon_o it_o 8_o motion_n sometime_o opposite_a to_o that_o of_o the_o movent_fw-la 9_o in_o a_o full_a medium_fw-la motion_n be_v propagate_v to_o any_o distance_n 10_o dilatation_n and_o contraction_n what_o they_o be_v 11_o dilatation_n and_o contraction_n suppose_v mutation_n of_o the_o small_a part_n in_o respect_n of_o their_o situation_n 12_o all_o traction_n be_v pulsion_n 13_o such_o thing_n as_o be_v press_v or_o bend_v restore_v themselves_o have_v motion_n in_o their_o internal_a part_n 14_o though_o that_o which_o carry_v another_o be_v stop_v the_o body_n carry_v will_v proceed_v 15_o 16_o the_o effect_n of_o percussion_n not_o to_o be_v compare_v with_o those_o of_o waight_n 17_o 18_o motion_n can_v begin_v first_o in_o the_o internal_a part_n of_o a_o body_n 19_o action_n and_o reaction_n proceed_v in_o the_o same_o line_n 20_o habit_n what_o it_o be_v 1_o i_o have_v already_o in_o the_o 15_o chap._n at_o the_o 2d_o article_n define_v endeavour_n to_o be_v motion_n through_o some_o length_n though_o not_o consider_v as_o length_n but_o as_o a_o point_n whether_o therefore_o there_o be_v resistance_n or_o no_o resistance_n the_o endeavour_n will_v still_o be_v the_o same_o for_o simple_o to_o endeavour_v be_v to_o go._n but_o when_o two_o body_n have_v opposite_a endeavour_n press_v one_o another_o than_o the_o endeavour_n of_o either_o of_o they_o be_v that_o which_o we_o call_v pressure_n and_o be_v mutual_a when_o their_o pressure_n be_v opposite_a 2._o body_n move_v and_o also_o the_o medium_n in_o which_o they_o be_v move_v be_v of_o two_o kind_n for_o either_o they_o have_v their_o part_n coherent_a in_o such_o manner_n as_o no_o part_n of_o the_o move_v body_n will_v easy_o yield_v to_o the_o movent_fw-la except_o the_o whole_a body_n yield_v also_o and_o such_o be_v the_o thing_n we_o call_v hard_a or_o else_o their_o part_n while_o the_o whole_a remain_v unmoved_a will_v easy_o yield_v to_o the_o movent_fw-la and_o these_o we_o call_v fluid_a or_o soft_a body_n for_o the_o word_n fluid_a soft_a tough_a and_o hard_a in_o the_o same_o manner_n as_o great_a and_o little_a be_v use_v only_o comparative_o and_o be_v not_o different_a kind_n but_o different_a degree_n of_o quality_n 3_o to_o do_v and_o to_o suffer_v be_v to_o move_v and_o to_o be_v move_v and_o nothing_o be_v move_v but_o by_o that_o which_o touch_v it_o and_o be_v also_o move_v as_o have_v be_v former_o show_v and_o how_o great_a sooner_o the_o distance_n be_v we_o say_v the_o first_o movent_fw-la move_v the_o last_o move_v body_n but_o mediate_o namely_o so_o as_o that_o the_o first_o move_v the_o second_o the_o second_o the_o three_o and_o so_o on_o till_o the_o last_o of_o all_o be_v touch_v when_o therefore_o one_o body_n have_v opposite_a endeavour_n to_o another_o body_n move_v the_o same_o and_o that_o move_v a_o three_o and_o so_o on_o i_o call_v that_o action_n propagation_n of_o motion_n 4_o when_o two_o fluid_a body_n which_o be_v in_o a_o free_a and_o open_a space_n press_v one_o another_o their_o part_n will_v endeavour_v or_o be_v move_v towards_o the_o side_n not_o only_o those_o part_n which_o be_v there_o where_o the_o mutual_a contact_n be_v but_o all_o the_o other_o part_n for_o in_o the_o first_o contact_n the_o part_n which_o be_v press_v by_o both_o the_o endeavour_v body_n have_v no_o place_n either_o forward_o or_o backward_o in_o which_o they_o can_v be_v move_v and_o therefore_o they_o be_v press_v out_o towards_o the_o side_n and_o this_o expressure_n when_o the_o force_n be_v equal_a be_v in_o a_o line_n perpendicular_a to_o the_o body_n press_v but_o whensoever_o the_o foremost_a part_n of_o both_o the_o body_n be_v press_v the_o hindermost_a also_o must_v be_v press_v at_o the_o same_o time_n for_o the_o motion_n of_o the_o hindermost_a part_n can_v in_o a_o instant_n be_v stop_v by_o the_o resistance_n of_o the_o foremost_a part_n but_o proceed_v for_o some_o time_n and_o therefore_o see_v they_o must_v have_v some_o place_n in_o which_o they_o may_v be_v move_v and_o that_o there_o be_v no_o place_n at_o all_o for_o they_o forward_o it_o be_v necessary_a that_o they_o be_v move_v into_o the_o place_n which_o be_v towards_o the_o side_n every_o way_n and_o this_o effect_n follow_v of_o necessity_n not_o only_o in_o fluid_a but_o in_o consistent_a and_o hard_a body_n though_o it_o be_v not_o always_o manifest_a to_o sense_n for_o though_o from_o the_o compression_n of_o two_o stone_n we_o can_v with_o our_o eye_n discern_v any_o swell_a outward_n towards_o the_o side_n as_o we_o perceive_v in_o two_o body_n of_o wax_n yet_o we_o know_v well_o enough_o by_o reason_n that_o some_o tumour_n must_v needs_o be_v there_o though_o it_o be_v but_o little_a 5_o but_o when_o the_o space_n be_v enclose_v and_o both_o the_o body_n be_v fluid_a they_o will_v if_o they_o be_v press_v together_o penetrate_v one_o anoteer_n though_o different_o according_a to_o their_o different_a endeavour_n for_o suppose_v a_o hollow_a cylinder_n of_o hard_a matter_n well_o stop_v at_o both_o end_n but_o fill_v first_o below_z with_o some_o heavy_a fluid_a body_n as_o quicksilver_n and_o above_o with_o water_n or_o aire_n if_o now_o the_o bottom_n of_o the_o cylinder_n be_v turn_v upward_o the_o heavy_a fluid_a body_n which_o be_v now_o at_o the_o top_n have_v the_o great_a endeavour_n downward_o and_o be_v by_o the_o hard_a side_n of_o the_o vessel_n hinder_v from_o extend_v itself_o sidewayes_o must_v of_o necessity_n either_o be_v receive_v by_o the_o light_a body_n that_o it_o may_v sink_v through_o it_o or_o else_o it_o must_v open_v a_o passage_n through_o itself_o by_o which_o the_o light_a body_n may_v ascend_v for_o of_o the_o two_o body_n that_o who_o part_n be_v most_o easy_o separate_v will_v the_o first_o be_v divide_v which_o be_v do_v it_o be_v not_o necessary_a that_o the_o part_n of_o the_o other_o suffer_v any_o separation_n at_o all_o and_o therefore_o when_o two_o liquor_n which_o be_v enclose_v in_o the_o same_o vessel_n change_v their_o place_n there_o be_v no_o need_n that_o their_o small_a part_n shall_v be_v mingle_v with_o one_o another_o for_o a_o way_n be_v open_v through_o one_o of_o they_o the_o part_n of_o the_o other_o need_v not_o be_v separate_v now_o if_o a_o fluid_a body_n which_o be_v not_o enclose_v press_v a_o hard_a body_n its_o endeavour_n will_v indeed_o be_v towards_o the_o internal_a part_n of_o that_o hard_a body_n but_o be_v exclude_v by_o the_o resistance_n of_o it_o the_o part_n of_o the_o fluid_a body_n will_v be_v move_v every_o way_n according_a to_o the_o superficies_n of_o the_o hard_a body_n and_o that_o equal_o if_o the_o pressure_n be_v perpendicular_a for_o when_o all_o the_o part_n of_o the_o cause_n be_v equal_a the_o effect_n will_v be_v equal_a also_o but_o if_o the_o pressure_n be_v not_o perpendicular_a than_o the_o angle_n of_o incidence_n be_v unequal_a the_o expansion_n also_o will_v be_v unequal_a namely_o great_a on_o that_o side_n where_o the_o angle_n be_v great_a because_o that_o motion_n be_v most_o direct_a which_o proceed_v by_o the_o direct_v line_n 6_o if_o a_o body_n press_v another_o body_n do_v not_o penetrate_v it_o it_o will_v nevertheless_o give_v to_o the_o part_n it_o press_v a_o endeavour_n to_o yield_v and_o recede_v
that_o which_o the_o line_n of_o incidence_n make_v with_o that_o line_n which_o from_o the_o point_n of_o refraction_n be_v draw_v perpendicular_a to_o the_o separate_a superficies_n 8_o the_o angle_n of_o incidence_n be_v the_o compliment_n to_o a_o right_a angle_n of_o the_o angle_n of_o inclination_n and_o so_o in_o the_o first_o figure_n the_o refraction_n be_v make_v in_o a_o b_o f._n the_o refracted_a line_n be_v b_o f._n the_o line_n of_o incidence_n be_v a_o b._n the_o point_n of_o incidence_n and_o of_o refraction_n be_v b._n the_o refract_n or_o separate_a superficies_n be_v d_o b_o e._n the_o line_n of_o incidence_n produce_v direct_o be_v a_o b_o c_o the_o perpendicular_a to_o the_o separate_a superficies_n be_v b_o h._n the_o angle_n of_o refraction_n be_v c_o b_o f._n the_o angle_n refract_v be_v h_n b_o f._n the_o angle_n of_o inclination_n be_v a_o b_o g_z or_o h_o b_o c._n the_o angle_n of_o incidence_n be_v a_o b_o d._n 9_o moreover_o the_o thin_a medium_fw-la be_v understand_v to_o be_v that_o in_o which_o there_o be_v less_o resistance_n to_o motion_n or_o to_o the_o generation_n of_o motion_n &_o the_o thick_a that_o wherein_o there_o be_v great_a resistance_n 10_o and_o that_o medium_fw-la in_o which_o there_o be_v equal_a resistance_n every_o where_o be_v a_o homogeneous_a medium_fw-la all_o other_o medium_n be_v heterogeneous_a 2_o if_o a_o body_n pass_v or_o there_o be_v generation_n of_o motion_n from_o one_o medium_fw-la to_o another_o of_o different_a density_n in_o a_o line_n perpendicular_a to_o the_o separate_a superficies_n there_o will_v be_v no_o refraction_n for_o see_v on_o every_o side_n of_o the_o perdendicular_a all_o thing_n in_o the_o medium_n be_v suppose_v to_o be_v like_a and_o equal_a if_o the_o motion_n itself_o be_v suppose_v to_o be_v perpendicular_a the_o inclination_n also_o will_v be_v equal_a or_o rather_o none_o at_o all_o and_o therefore_o there_o can_v be_v no_o cause_n from_o which_o refraction_n may_v be_v infer_v to_o be_v on_o one_o side_n of_o the_o perpendicular_a which_o will_v not_o conclude_v the_o same_o refraction_n to_o be_v on_o the_o other_o side_n which_o be_v so_o refraction_n on_o one_o side_n will_v destroy_v refraction_n on_o the_o other_o side_n and_o consequent_o either_o the_o refracted_a line_n will_v be_v every_o where_o which_o be_v absurd_a or_o there_o will_v be_v no_o refracted_a line_n at_o all_o which_o be_v to_o be_v demonstrate_v corol._n it_o be_v manifest_a from_o hence_o that_o the_o cause_n of_o refraction_n consist_v only_o in_o the_o obliquity_n of_o the_o line_n of_o incidence_n whether_o the_o incident_a body_n penetrate_v both_o the_o medium_n or_o without_o penetrate_v propagate_v motion_n by_o pressure_n only_o 3_o if_o a_o body_n without_o any_o change_n of_o situation_n of_o its_o internal_a part_n as_o a_o stone_n be_v move_v oblique_o out_o of_o the_o thin_a medium_fw-la and_o proceed_v penetrate_v the_o thick_a medium_fw-la and_o the_o thick_a medium_fw-la be_v such_o as_o that_o its_o internal_a part_n be_v move_v restore_v themselves_o to_o their_o former_a situation_n the_o angle_n refract_v will_v be_v great_a than_o the_o angle_n of_o inclination_n for_o let_v d_o b_o e_o in_o the_o same_o first_o figure_n be_v the_o separate_a superficies_n of_o two_o medium_n and_o let_v a_o body_n as_o a_o stone_n throw_v be_v understand_v to_o be_v move_v as_o be_v suppose_v in_o the_o straight_a line_n a_o b_o c_o and_o let_v a_o b_o be_v in_o the_o thin_a medium_fw-la as_o in_o the_o air_n and_o b_o c_o in_o the_o thick_a as_o in_o the_o water_n i_o say_v the_o stone_n w_z ch_z be_v throw_v be_v move_v in_o the_o line_n a_o b_o will_n not_o proceed_v in_o the_o line_n b_o c_o but_o in_o some_o other_o line_n namely_o that_o with_o which_o the_o perpendicular_a b_o h_n make_v the_o refracted_a angle_n h_o b_o f_o great_a than_o the_o angle_n of_o inclination_n h_n b_o c._n for_o see_v the_o stone_n come_v from_o a_o and_o fall_v upon_o b_o makes_z that_o which_o be_v at_o b_o proceed_v towards_o h_n and_o that_o the_o like_a be_v do_v in_o all_o the_o straight_a line_n which_o be_v parallel_v to_o b_o h_n and_o see_v the_o part_n move_v restore_v themselves_o by_o contrary_a motion_n in_o the_o same_o line_n there_o will_v be_v contrary_a motion_n generate_v in_o h_n b_o and_o in_o all_o the_o straight_a line_n which_o be_v parallel_v to_o it_o wherefore_o the_o motion_n of_o the_o stone_n will_v be_v make_v by_o the_o concourse_n of_o the_o motion_n in_o a_o g_o that_o be_v in_o d_o b_o and_o in_o g_z b_o that_o be_v in_o b_o h_n and_o last_o in_o h_n b_o that_o be_v by_o the_o concourse_n of_o three_o motion_n but_o by_o the_o concourse_n of_o the_o motion_n in_o a_o g_o and_o b_o h_n the_o stone_n will_v be_v carry_v to_o c_o and_o therefore_o by_o add_v the_o motion_n in_o h_n b_o it_o will_v be_v carry_v high_a in_o some_o other_o line_n as_o in_o b_o f_o and_o make_v the_o angle_n h_o b_o f_o great_a than_o the_o angle_n h_o b_o c._n and_o from_o hence_o may_v be_v derive_v the_o cause_n why_o body_n which_o be_v throw_v in_o a_o very_a oblique_a line_n if_o either_o they_o be_v any_o thing_n flat_a or_o be_v throw_v with_o great_a force_n will_v when_o they_o fall_v upon_o the_o water_n be_v cast_v up_o again_o from_o the_o water_n into_o the_o air_n for_o let_v a_o b_o in_o the_o 2d_o figure_n be_v the_o superficies_n of_o the_o water_n into_o which_o from_o the_o point_n c_o let_v a_o stone_n be_v throw_v in_o the_o straight_a line_n c_o a_o make_v with_o the_o line_n b_o a_o produce_v a_o very_a little_a angle_n c_o a_o d_o and_o produce_v b_o a_o indefinite_o to_o d_o let_v c_o d_o be_v draw_v perpendicular_a to_o it_o and_o a_o e_z parallel_n to_o c_o d._n the_o stone_n therefore_o will_v be_v move_v in_o c_o a_o by_o the_o concourse_n of_o two_o motion_n in_o c_o d_o and_o d_o a_o who_o velocity_n be_v as_o the_o line_n themselves_o c_o d_o and_o d_o a._n and_o from_o the_o motion_n in_o c_o d_o and_o all_o its_o parallel_n downward_o as_o soon_o as_o the_o stone_n fall_v upon_o a_o there_o will_v be_v reaction_n upward_o because_o the_o water_n restore_v itself_o to_o its_o former_a situation_n if_o now_o the_o stone_n be_v throw_v with_o sufficient_a obliquity_n that_o be_v if_o the_o straight_a line_n c_o d_o be_v short_a enough_o that_o be_v if_o the_o endeavour_n of_o the_o stone_n downward_o be_v less_o than_o the_o reaction_n of_o the_o water_n upward_o that_o be_v less_o than_o the_o endeavour_v it_o have_v from_o its_o own_o gravity_n for_o that_o may_v be_v the_o stone_n will_v by_o reason_n of_o the_o excess_n of_o the_o endeavour_n which_o the_o water_n have_v to_o restore_v itself_o above_o that_o which_o the_o stone_n have_v downward_o be_v raise_v again_o above_o the_o superficies_n a_o b_o and_o be_v carry_v high_a be_v reflect_v in_o a_o line_n which_o go_v high_o as_o the_o line_n a_o g._n 4_o if_o from_o a_o point_n whatsoever_o the_o medium_fw-la be_v endeavour_v be_v propagate_v every_o way_n into_o all_o the_o part_n of_o that_o medium_fw-la and_o to_o the_o same_o endeavour_n there_o be_v oblique_o oppose_v another_o medium_fw-la of_o a_o different_a nature_n that_o be_v either_o thin_a or_o thick_a that_o endeavour_n will_v be_v so_o refract_v that_o the_o sine_fw-la of_o the_o angle_n refract_v to_o the_o sine_fw-la of_o the_o angle_n of_o inclination_n will_v be_v as_o the_o density_n of_o the_o first_o medium_fw-la to_o the_o density_n of_o the_o second_o medium_fw-la reciprocal_o take_v first_o let_v a_o body_n be_v in_o the_o thin_a medium_fw-la in_o a_o figure_n 3d._n and_o let_v it_o be_v understand_v to_o have_v endeavour_v every_o way_n and_o consequent_o that_o its_o endeavour_n proceed_v in_o the_o line_n a_o b_o and_o a_o b_o to_o which_o let_v b_o b_o the_o superficies_n of_o the_o thick_a medium_fw-la be_v oblique_o oppose_v in_o b_o and_o b_o so_o that_o a_o b_o and_o a_o b_o be_v equal_a and_o let_v the_o straight_a line_n b_o b_o be_v produce_v both_o way_n from_o the_o point_n b_o and_o b_o let_v the_o perpendicular_n b_o c_o and_o b_o c_o be_v draw_v and_o upon_o the_o centre_n b_o and_o b_o and_o at_o the_o equal_a distance_n b_o a_n and_o b_o a_o let_v the_o circle_n a_o c_o and_o a_o c_o be_v describe_v cut_v b_o c_o and_o b_o c_o in_o c_o and_o c_o and_o the_o same_o c_o b_o and_o c_o b_o produce_v in_o d_o and_o d_o as_o also_o a_o b_o and_o a_o b_o produce_v in_o e_z and_o e._n then_o from_o the_o point_n a_o to_o the_o straight_a line_n b_o c_o and_o b_o c_o let_v the_o perpendicular_o
at_o several_a time_n be_v by_o vehemence_n make_v strong_a and_o more_o predominant_a than_o the_o rest_n which_o deprive_v we_o of_o the_o sense_n of_o other_o phantasm_n no_o otherwise_o then_o the_o sun_n deprive_v the_o rest_n of_o the_o star_n of_o light_n not_o by_o hinder_v their_o action_n but_o by_o obscure_v and_o hide_v they_o with_o his_o excess_n of_o brightness_n 7._o but_o the_o motion_n of_o the_o organ_n by_o which_o a_o phantasm_n be_v make_v be_v not_o common_o call_v sense_n except_o the_o object_n be_v present_a and_o the_o phantasm_n remain_v after_o the_o object_n be_v remove_v or_o pass_v by_o be_v call_v fancy_n and_o in_o latin_a imaginatio_fw-la which_o word_n because_o all_o phantasm_n be_v not_o image_n do_v not_o full_o answer_v the_o signification_n of_o the_o word_n fancy_n in_o its_o general_a acceptation_n nevertheless_o i_o may_v use_v it_o safe_o enough_o by_o understand_v it_o for_o the_o greek_a 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d imagination_n therefore_o be_v nothing_o else_o but_o sense_n decay_v or_o weaken_v by_o the_o absence_n of_o the_o object_n but_o what_o may_v be_v the_o cause_n of_o this_o decay_n or_o weaken_n be_v the_o motion_n the_o weak_a because_o the_o object_n be_v take_v away_o if_o it_o be_v than_o phantasm_n will_v always_o and_o necessary_o be_v less_o clear_a in_o the_o imagination_n than_o they_o be_v in_o sense_n which_o be_v not_o true_a for_o in_o dream_n which_o be_v the_o imagination_n of_o those_o that_o sleep_n they_o be_v no_o less_o clear_a than_o in_o sense_n itself_o but_o the_o reason_n why_o in_o man_n wake_v the_o phantasm_n of_o thing_n past_a be_v more_o obscure_a than_o those_o of_o thing_n present_a be_v this_o that_o their_o organ_n be_v at_o the_o same_o time_n move_v by_o other_o present_a object_n those_o phantasm_n be_v the_o less_o predominant_a whereas_o in_o sleep_n the_o passage_n be_v shut_v up_o external_a action_n do_v not_o at_o all_o disturb_v or_o hinder_v internal_a motion_n if_o this_o be_v true_a the_o next_o thing_n to_o be_v consider_v will_v be_v whether_o any_o cause_n may_v be_v find_v out_o from_o the_o supposition_n whereof_o it_o will_v follow_v that_o the_o passage_n be_v shut_v up_o from_o the_o external_a object_n of_o sense_n to_o the_o internal_a organ_n i_o suppose_v therefore_o that_o by_o the_o continual_a action_n of_o object_n to_o which_o a_o reaction_n of_o the_o organ_n and_o more_o esqecial_o of_o the_o spirit_n be_v necessary_o consequent_a the_o organ_n be_v weary_v that_o be_v its_o part_n be_v no_o long_o move_v by_o the_o spirit_n without_o some_o pain_n and_o consequent_o the_o nerve_n be_v abandon_v and_o grow_v slack_a they_o retire_v to_o their_o fountain_n which_o be_v the_o cavity_n either_o of_o the_o brain_n or_o of_o the_o heart_n by_o which_o mean_v the_o action_n which_o proceed_v by_o the_o nerve_n be_v necessary_o intercept_v for_o action_n upon_o a_o patient_n that_o retire_v from_o it_o make_v but_o little_a impression_n at_o the_o first_o and_o at_o last_o when_o the_o nerve_n be_v by_o little_a and_o little_o slacken_v none_o at_o all_o and_o therefore_o there_o be_v no_o more_o reaction_n that_o be_v no_o more_o sense_n till_o the_o organ_n be_v refresh_v by_o rest_n and_o by_o a_o supply_n of_o new_a spirit_n recover_v strength_n and_o motion_n the_o sentient_n awake_v and_o thus_o it_o seem_v to_o be_v always_o unless_o some_o other_o preternatural_a cause_n intervene_v as_o heat_n in_o the_o internal_a part_n from_o lassitude_n or_o from_o some_o disease_n stir_v the_o spirit_n and_o other_o part_n of_o the_o organ_n in_o some_o extraordinary_a manner_n 8_o now_o it_o be_v not_o without_o cause_n nor_o so_o casual_a a_o thing_n as_o many_o perhaps_o think_v it_o that_o phantasm_n in_o this_o their_o great_a variety_n proceed_v from_o one_o another_o and_o that_o the_o same_o phantasm_n sometime_o bring_v into_o the_o mind_n other_o phantasm_n like_o themselves_o and_o at_o other_o time_n extreme_o unlike_a for_o in_o the_o motion_n of_o any_o continue_a body_n one_o part_n follow_v another_o by_o cohaesion_n and_o therefore_o whilst_o we_o turn_v our_o eye_n and_o other_o organ_n successive_o to_o many_o object_n the_o motion_n which_o be_v make_v by_o every_o one_o of_o they_o remain_v the_o phantasm_n be_v renew_v as_o often_o as_o any_o of_o those_o motion_n come_v to_o be_v predominant_a above_o the_o rest_n and_o they_o become_v predominant_a in_o the_o same_o order_n in_o which_o at_o any_o time_n former_o they_o be_v generate_v by_o sense_n so_o that_o when_o by_o length_n of_o time_n very_o many_o phantasm_n have_v be_v generate_v within_o we_o by_o sense_n than_o almost_o any_o thought_n may_v arise_v from_o any_o other_o thought_n in_o so_o much_o that_o it_o may_v seem_v to_o be_v a_o thing_n indifferent_a and_o casual_a which_o thought_n shall_v follow_v which_o but_o for_o the_o most_o part_n this_o be_v not_o so_o uncertain_a a_o thing_n to_o wake_v as_o to_o sleep_a man_n for_o the_o thought_n or_o phantasm_n of_o the_o desire_a end_n bring_v in_o all_o the_o phantasm_n that_o be_v mean_n conduce_v to_o that_o end_n and_o that_o in_o order_n backwards_o from_o the_o last_o to_o the_o first_o and_o again_o forward_o from_o the_o beginning_n to_o the_o end_n but_o this_o suppose_v both_o appetite_n and_o judgement_n to_o discern_v what_o mean_v conduce_v to_o the_o end_n which_o be_v get_v by_o experience_n and_o experience_n be_v store_n of_o phantasm_n arise_v from_o the_o sense_n of_o very_a many_o thing_n for_o 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d and_o meminisse_fw-la fancy_n and_o memory_n differ_v only_o in_o this_o that_o memory_n suppose_v the_o time_n past_a which_o fancy_n do_v not_o in_o memory_n the_o phantasm_n we_o consider_v be_v as_o if_o they_o be_v wear_v out_o with_o time_n but_o in_o our_o fancy_n we_o consider_v they_o as_o they_o be_v which_o distinction_n be_v not_o of_o the_o thing_n themselves_o but_o of_o the_o consideration_n of_o the_o sentient_a for_o there_o be_v in_o memory_n something_o like_o that_o which_o happen_v in_o look_v upon_o thing_n at_o a_o great_a distance_n in_o which_o as_o the_o small_a part_n of_o the_o object_n be_v not_o discern_v by_o reason_n of_o their_o remoteness_n so_o in_o memory_n many_o accident_n and_o place_n and_o part_n of_o thing_n which_o be_v former_o perceive_v by_o sense_n be_v by_o length_n of_o time_n decay_v and_o lose_v the_o perpetual_a arise_v of_o phantasm_n both_o in_o sense_n and_o imagination_n be_v that_o which_o we_o common_o call_v discourse_n of_o the_o mind_n and_o be_v common_a to_o man_n with_o other_o live_a creature_n for_o he_o thta_fw-la think_v compare_v the_o phantasm_n that_o pass_v that_o be_v take_v notice_n of_o their_o likeness_n or_o unlikeness_n to_o one_o another_o and_o as_o he_o that_o observe_v ready_o the_o likeness_n of_o thing_n of_o different_a nature_n or_o that_o be_v very_o remote_a from_o one_o another_o be_v say_v to_o have_v a_o good_a fancy_n so_o he_o be_v say_v to_o have_v a_o good_a judgement_n that_o find_v out_o the_o unlikeness_n or_o difference_n of_o thing_n that_o be_v like_o one_o another_o now_o this_o observation_n of_o difference_n be_v not_o perception_n make_v by_o a_o common_a organ_n of_o sense_n distinct_a from_o sense_n or_o perception_n proper_o so_o call_v but_o be_v memory_n of_o the_o difference_n of_o particular_a phantasm_n remain_v for_o some_o time_n as_o the_o distinction_n between_o hot_a and_o lucid_a be_v nothing_o else_o but_o the_o memory_n both_o of_o a_o heat_n and_o of_o a_o enlighten_v object_n 9_o the_o phantasm_n of_o man_n that_o sleep_v be_v dream_n concern_v which_o we_o be_v teach_v by_o experience_n these_o five_o thing_n first_o that_o for_o the_o most_o part_n there_o be_v neither_o order_n nor_o coherence_n in_o they_o second_o that_o we_o dream_v of_o nothing_o but_o what_o be_v compound_v and_o make_v up_o of_o the_o phantasm_n of_o sense_n past_a three_o that_o sometime_o they_o proceed_v as_o in_o those_o that_o be_v drowsy_a from_o the_o interruption_n of_o their_o phantasm_n by_o little_a and_o little_o break_v and_o alter_v through_o sleepiness_n and_o sometime_o also_o they_o begin_v in_o the_o midst_n of_o sleep_n four_o that_o they_o be_v clear_a than_o the_o imagination_n of_o wake_a man_n except_o such_o as_o be_v make_v by_o sense_n itself_o to_o which_o they_o be_v equal_a in_o clearness_n five_o that_o when_o we_o dream_v we_o admire_v neither_o the_o place_n nor_o the_o look_n of_o the_o thing_n that_o appear_v to_o we_o now_o from_o what_o have_v be_v say_v it_o be_v not_o hard_a to_o show_v what_o may_v be_v the_o cause_n of_o these_o phaenomena_n for_o as_o for_o the_o first_o see_v all_o order_n and_o coherence_n proceed_v from_o frequent_a
nothing_o but_o perturb_a light_n be_v comprehend_v wherefore_o the_o phantasm_n of_o a_o lucid_a body_n be_v light_n and_o of_o a_o colour_a body_n colour_n but_o the_o object_n of_o sight_n proper_o so_o call_v be_v neither_o light_n nor_o colour_n but_o the_o body_n itself_o which_o be_v lucid_a or_o enlighten_v or_o colour_v for_o light_n and_o colour_n be_v phantasm_n of_o the_o sentient_a can_v be_v accident_n of_o the_o object_n which_o be_v manifest_a enough_o from_o this_o that_o visible_a thing_n appear_v oftentimes_o in_o place_n in_o which_o we_o know_v assure_o they_o be_v not_o and_o that_o in_o different_a place_n they_o be_v of_o different_a colour_n and_o may_v at_o one_o and_o the_o same_o time_n appear_v in_o divers_a place_n motion_n rest_v magnitude_n and_o figure_n be_v common_a both_o to_o the_o sight_n and_o touch_n and_o the_o whole_a appearance_n together_o of_o figure_n and_o light_n or_o colour_n be_v by_o the_o greek_n common_o call_v 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d and_o by_o the_o latin_n species_n and_o imago_fw-la all_o which_o name_n signify_v no_o more_o but_o appearance_n the_o phantasm_n which_o be_v make_v by_o hear_v be_v sound_a by_o smell_n odour_n by_o taste_n savour_n and_o by_o touch_n hardness_n and_o softness_n heat_n and_o cold_a wetness_n oiliness_n and_o many_o more_o which_o be_v easy_a to_o be_v distinguish_v by_o sense_n then_o word_n smoothness_n roughness_n rarity_n and_o density_n refer_v to_o figure_n and_o be_v therefore_o common_a both_o to_o touch_v and_o sight_n and_o as_o for_o the_o object_n of_o hear_v smell_v taste_n and_o touch_v they_o be_v not_o sound_v odour_n savour_n hardness_n etc._n etc._n but_o the_o body_n themselves_o from_o which_o sound_n odour_n savour_n hardness_n etc._n etc._n proceed_v of_o the_o cause_n of_o which_o and_o of_o the_o manner_n how_o they_o be_v produce_v i_o shall_v speak_v hereafter_o but_o these_o phantasm_n though_o they_o be_v effect_n in_o the_o sentient_a as_o subject_a produce_v by_o object_n work_v upon_o the_o organ_n yet_o there_o be_v also_o other_o effect_n beside_o these_o produce_v by_o the_o same_o object_n in_o the_o same_o organ_n namely_o certain_a motion_n proceed_v from_o sense_n which_o be_v call_v animal_n motion_n for_o see_v in_o all_o sense_n of_o external_a thing_n there_o be_v mutual_a action_n and_o reaction_n that_o be_v two_o endeavour_n oppose_v one_o another_o it_o be_v manifest_a that_o the_o motion_n of_o both_o of_o they_o together_o will_v be_v continue_v every_o way_n especial_o to_o the_o confine_n of_o both_o the_o body_n and_o when_o this_o happen_v in_o the_o internal_a organ_n the_o endeavour_n outward_o will_v proceed_v in_o a_o solid_a angle_n which_o will_v be_v great_a and_o consequent_o the_o idea_n great_a than_o it_o will_v have_v be_v if_o the_o impression_n have_v be_v weak_a 11_o from_o hence_o the_o natural_a cause_n be_v manifest_a first_o why_o those_o thing_n seem_v to_o be_v great_a which_o caeteris_fw-la paribus_fw-la be_v see_v in_o a_o great_a angle_n second_o why_o in_o a_o serene_a cold_a night_n when_o the_o moon_n do_v not_o shine_v more_o of_o the_o fix_a star_n appear_v then_o at_o another_o time_n for_o their_o action_n be_v less_o hinder_v by_o the_o serenity_n of_o the_o air_n and_o not_o obscure_v by_o the_o great_a light_n of_o the_o moon_n which_o be_v then_o absent_a and_o the_o cold_a make_v the_o air_n more_o press_v help_v or_o strengthen_v the_o action_n of_o the_o star_n upon_o our_o eye_n in_o so_o much_o as_o star_n may_v then_o be_v see_v which_o be_v see_v at_o no_o other_o time_n and_o this_o may_v suffice_v to_o be_v say_v in_o general_a concern_v sense_n make_v by_o the_o reaction_n of_o the_o organ_n for_o as_o for_o the_o place_n of_o the_o image_n the_o deception_n of_o sight_n and_o other_o thing_n of_o which_o we_o have_v experience_n in_o ourselves_o by_o sense_n be_v they_o depend_v for_o the_o most_o part_n upon_o the_o fabric_n itself_o of_o the_o eye_n of_o man_n i_o shall_v speak_v of_o they_o then_o when_o i_o come_v to_o speak_v of_o man._n 12_o but_o there_o be_v another_o kind_n of_o sense_n of_o which_o i_o will_v say_v something_o in_o this_o place_n namely_o the_o sense_n of_o pleasure_n and_o pain_n proceed_v not_o from_o the_o reaction_n of_o the_o heart_n outward_o but_o from_o continual_a action_n from_o the_o outermost_a part_n of_o the_o organ_n towards_o the_o heart_n for_o the_o original_n of_o life_n be_v in_o the_o heart_n that_o motion_n in_o the_o sentient_n which_o be_v propagate_v to_o the_o heart_n must_v necessary_o make_v some_o alteration_n or_o diversion_n of_o vital_a motion_n namely_o by_o quicken_a or_o slacken_a help_a or_o hinder_v the_o same_o now_o when_o it_o help_v it_o be_v pleasure_n and_o when_o it_o hinder_v it_o be_v pain_n trouble_v grief_n etc._n etc._n and_o as_o phantasm_n seem_v to_o be_v without_o by_o reason_n of_o the_o endeavour_n outward_o so_o pleasure_n and_o pain_n by_o reason_n of_o the_o endeavour_n of_o the_o organ_n inward_o seem_v to_o be_v within_o namely_o there_o where_o the_o first_o cause_n of_o the_o pleasure_n or_o pain_n be_v as_o when_o the_o pain_n proceed_v from_o a_o wound_n we_o think_v the_o pain_n and_o the_o wound_n be_v both_o in_o the_o same_o place_n now_o vital_a motion_n be_v the_o motion_n of_o the_o blood_n perpetual_o circulate_v as_o have_v be_v show_v from_o many_o infallible_a sign_n and_o mark_n by_o doctor_n harvey_n the_o first_o observer_n of_o it_o in_o the_o vein_n and_o artery_n which_o motion_n when_o it_o be_v hinder_v by_o some_o other_o motion_n make_v by_o the_o action_n of_o sensible_a object_n may_v be_v restore_v again_o either_o by_o bend_v or_o set_v straight_o the_o part_n of_o the_o body_n which_o be_v do_v when_o the_o spirit_n be_v carry_v now_o into_o these_o now_o into_o other_o nerve_n till_o the_o pain_n as_o far_o as_o be_v possible_a be_v quite_o take_v away_o but_o if_o vital_a motion_n be_v help_v by_o motion_n make_v by_o sense_n than_o the_o part_n of_o the_o organ_n will_v be_v dispose_v to_o guide_v the_o spirit_n in_o such_o manner_n as_o conduce_v most_o to_o the_o preservation_n and_o augmentation_n of_o that_o motion_n by_o the_o help_n of_o the_o nerve_n and_o in_o animal_n motion_n this_o be_v the_o very_a first_o endeavour_n and_o find_v even_o in_o the_o embryo_n which_o while_o it_o be_v in_o the_o womb_n move_v its_o limb_n with_o voluntary_a motion_n for_o the_o avoid_n of_o whatsoever_o trouble_v it_o or_o for_o the_o pursue_v of_o what_o please_v it_o and_o this_o first_o endeavour_n when_o it_o tend_v towards_o such_o thing_n as_o be_v know_v by_o experience_n to_o be_v pleasant_a be_v call_v appetite_n that_o be_v a_o approach_v and_o when_o it_o shun_v what_o be_v troublesome_a aversion_n or_o fly_v from_o it_o and_o little_a infant_n at_o the_o beginning_n and_o as_o soon_o as_o they_o be_v bear_v have_v appetite_n to_o very_o 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a_o ready_a use_n of_o their_o nerve_n and_o other_o organ_n in_o the_o pursue_n and_o avoid_v of_o good_a and_o bad_a wherefore_o appetite_n and_o aversion_n be_v the_o first_o endeavour_n of_o animal_n motion_n consequent_a to_o this_o first_o endeavour_n be_v the_o impulsion_n into_o the_o nerve_n and_o retraction_n again_o of_o animal_n spirit_n of_o which_o it_o be_v necessary_a there_o be_v some_o receptacle_n on_o place_n near_o the_o original_n of_o the_o nerve_n and_o this_o motion_n or_o endeavour_n be_v follow_v by_o a_o swell_a and_o relaxation_n of_o the_o muscle_n and_o last_o these_o be_v follow_v by_o contraction_n and_o extension_n of_o the_o limb_n which_o be_v animal_n motion_n 13_o the_o consideration_n of_o appetite_n and_o aversion_n be_v divers_a for_o see_v live_a creature_n have_v sometime_o appetite_n and_o
sometime_o aversion_n to_o the_o same_o thing_n as_o they_o think_v it_o will_v either_o be_v for_o their_o good_a or_o their_o hurt_n while_o that_o vicissitude_n of_o appetite_n and_o aversion_n remain_v in_o they_o they_o have_v that_o series_n of_o thought_n which_o be_v call_v deliberation_n which_o last_v as_o long_o as_o they_o have_v it_o in_o their_o power_n to_o obtain_v that_o which_o please_v or_o to_o avoid_v that_o which_o displease_v they_o appetite_n therefore_o and_o aversion_n be_v simple_o so_o call_v as_o long_o as_o they_o follow_v not_o deliberation_n but_o if_o deliberation_n have_v go_v before_o than_o the_o last_o act_n of_o it_o if_o it_o be_v appetite_n be_v call_v will_n if_o aversion_n unwillingness_n so_o that_o the_o same_o thing_n be_v call_v both_o will_n and_o appetite_n but_o the_o consideration_n of_o they_o namely_o before_o and_o after_o deliberation_n be_v divers_a nor_o be_v that_o which_o be_v do_v within_o a_o man_n while_o he_o will_v any_o thing_n different_a from_o that_o which_o be_v do_v in_o other_o live_a creature_n while_o deliberation_n have_v precede_v they_o have_v appetite_n neither_o be_v the_o freedom_n of_o willing_a or_o not_o will_v great_a in_o man_n then_o in_o other_o live_a creature_n for_o where_o there_o be_v appetite_n the_o entire_a cause_n of_o appetite_n have_v precede_v and_o consequent_o the_o act_n of_o appetite_n can_v not_o choose_v but_o follow_v that_o be_v have_v of_o necessity_n follow_v as_o be_v show_v chapt._n 9th_o article_n 5._o and_o therefore_o such_o a_o liberty_n as_o be_v free_a from_o necessity_n be_v not_o to_o be_v find_v in_o the_o will_v either_o of_o man_n or_o beast_n but_o if_o by_o liberty_n we_o understand_v the_o faculty_n or_o power_n not_o of_o willing_a but_o of_o do_v what_o they_o will_v then_o certain_o that_o liberty_n be_v to_o be_v allow_v to_o both_o and_o both_o may_v equal_o have_v it_o whensover_v it_o be_v to_o be_v have_v again_o when_o appetite_n and_o aversion_n do_v with_o celerity_n succeed_v one_o another_o the_o whole_a series_n make_v by_o they_o have_v its_o name_n sometime_o from_o one_o sometime_o from_o the_o other_o for_o the_o same_o deliberation_n while_o it_o incline_v sometime_o to_o one_o sometime_o to_o the_o other_o be_v from_o appetite_n call_v hope_n and_o from_o aversion_n fear_v for_o where_o there_o be_v no_o hope_n it_o be_v not_o to_o be_v call_v fear_n but_o hate_v and_o where_o no_o fear_n not_o hope_n but_o desire_v to_o conclude_v all_o the_o passion_n call_v passion_n of_o the_o mind_n consist_v of_o appetite_n and_o aversion_n except_o pure_a pleasure_n and_o pain_n which_o be_v a_o certain_a fruition_n of_o good_a or_o evil_a as_o anger_n be_v aversion_n from_o some_o imminent_a evil_n but_o such_o as_o be_v join_v with_o appetite_n of_o avoid_v that_o evil_a by_o force_n but_o because_o the_o passion_n and_o perturbation_n of_o the_o mind_n be_v innumerable_a and_o many_o of_o they_o not_o to_o be_v discern_v in_o any_o creature_n beside_o man_n i_o will_v speak_v of_o they_o more_o at_o large_a in_o that_o section_n which_o be_v concern_v man._n as_o for_o those_o object_n if_o there_o be_v any_o such_o which_o do_v not_o at_o all_o stir_v the_o mind_n we_o be_v say_v to_o contemn_v they_o and_o thus_o much_o of_o sense_n in_o general_n in_o the_o next_o place_n i_o shall_v speak_v of_o sensible_a object_n chap._n xxvi_o of_o the_o world_n and_o of_o the_o star_n 1_o the_o magnitude_n and_o duration_n of_o the_o world_n inscrutable_a 2_o no_o place_n in_o the_o world_n empty_a 3_o the_o argument_n of_o lucretius_n for_o vacuum_n invalid_a 4_o other_o argument_n for_o the_o establish_n of_o vacuum_n invalid_a 5_o six_o supposition_n for_o the_o salve_v of_o the_o phaenomena_n of_o nature_n 6_o possible_a cause_n of_o the_o motion_n annual_a and_o diurnal_a and_o of_o the_o apparent_a direction_n station_n and_o retrogradation_n of_o the_o planet_n 7_o the_o supposition_n of_o simple_a motion_n why_o likely_a 8_o the_o cause_n of_o the_o excentricity_n of_o the_o annual_a motion_n of_o the_o earth_n 9_o the_o cause_n why_o the_o moon_n have_v always_o one_o and_o the_o same_o face_n turn_v towards_o the_o earth_n 10_o the_o cause_n of_o the_o tide_n of_o the_o ocean_n 11_o the_o cause_n of_o the_o praecession_n of_o the_o equinox_n 1_o consequent_a to_o the_o contemplation_n of_o sense_n be_v the_o contemplation_n of_o body_n which_o be_v the_o efficient_a cause_n or_o object_n of_o sense_n now_o every_o object_n be_v either_o a_o part_n of_o the_o whole_a world_n or_o a_o aggregate_v of_o part_n the_o great_a of_o all_o body_n or_o sensible_a object_n be_v the_o world_n itself_o which_o we_o behold_v when_o we_o look_v round_o about_o we_o from_o this_o point_n of_o the_o same_o which_o we_o call_v the_o earth_n concern_v the_o world_n as_o it_o be_v one_o aggregate_v of_o many_o part_n the_o thing_n that_o fall_v under_o inquiry_n be_v but_o few_o and_o those_o we_o can_v determine_v none_o of_o the_o whole_a world_n we_o may_v inquire_v what_o be_v its_o magnitude_n what_o its_o duration_n and_o how_o many_o there_o be_v but_o nothing_o else_o for_o as_o for_o place_n and_o time_n that_o be_v to_o say_v magnitude_n and_o duration_n they_o be_v only_o our_o own_o fancy_n of_o a_o body_n simple_o so_o call_v that_o be_v to_o say_v of_o a_o body_n indefinite_o take_v as_o i_o have_v show_v before_o in_o the_o 7_o chapter_n all_o other_o phantasm_n be_v of_o body_n or_o object_n as_o they_o be_v distinguish_v from_o one_o another_o as_o colour_n the_o phantasm_n of_o colour_a body_n sound_v of_o body_n that_o move_v the_o sense_n of_o hear_v etc._n etc._n the_o question_n concern_v the_o magnitude_n of_o the_o world_n be_v whether_o it_o be_v finite_a or_o infinite_a full_a or_o not_o full_a concern_v its_o duration_n whether_o it_o have_v a_o beginning_n or_o be_v eternal_a and_o concern_v the_o number_n whether_o there_o be_v one_o or_o many_o though_o as_o concern_v the_o number_n if_o it_o be_v of_o infinite_a magnitude_n there_o can_v be_v no_o controversy_n at_o all_o also_o if_o it_o have_v a_o beginning_n then_o by_o what_o cause_n and_o of_o what_o matter_n it_o be_v make_v and_o again_o from_o whence_o that_o cause_n and_o that_o matter_n have_v their_o be_v will_v be_v new_a question_n till_o at_o last_o we_o come_v to_o one_o or_o many_o eternal_a cause_n or_o cause_n and_o the_o determination_n of_o all_o these_o thing_n belong_v to_o he_o that_o profess_v the_o universal_a doctrine_n of_o philosophy_n in_o case_n as_o much_o can_v be_v know_v as_o can_v be_v seek_v but_o the_o knowledge_n of_o what_o be_v infinite_a can_v never_o be_v attain_v by_o a_o finite_a inquirer_n whatsoever_o we_o know_v that_o be_v man_n we_o learn_v it_o from_o our_o phantasm_n and_o of_o infinite_a whether_o magnitude_n or_o time_n there_o be_v no_o phantasm_n at_o all_o so_o that_o it_o be_v impossible_a either_o for_o a_o man_n or_o any_o other_o creature_n to_o have_v any_o conception_n of_o infinite_a and_o though_o a_o man_n may_v from_o some_o effect_n proceed_v to_o the_o immediate_a cause_n thereof_o &_o from_o that_o to_o a_o more_o remote_a cause_n and_o so_o ascend_v continual_o by_o right_a ratiocination_n from_o cause_n to_o cause_n yet_o he_o will_v not_o be_v able_a to_o proceed_v eternal_o but_o weary_v will_v at_o last_o give_v over_o without_o know_v whether_o it_o be_v possible_a for_o he_o to_o proceed_v to_o a_o end_n or_o not_o but_o whether_o we_o suppose_v the_o world_n to_o be_v finite_a or_o infinite_a no_o absurdity_n will_v follow_v for_o the_o same_o thing_n which_o now_o appear_v may_v appear_v whether_o the_o creator_n have_v please_v it_o shall_v be_v finite_a or_o infinite_a beside_o though_o from_o this_o that_o nothing_o can_v move_v itself_o it_o may_v right_o be_v infer_v that_o there_o be_v some_o first_o eternal_a movent_fw-la yet_o it_o can_v never_o be_v infer_v though_o some_o use_n to_o make_v such_o inference_n that_o that_o movent_fw-la be_v eternal_o immovable_a but_o rather_o eternal_o move_v for_o as_o it_o be_v true_a that_o nothing_o be_v move_v by_o itself_o so_o it_o be_v true_a also_o that_o nothing_o be_v move_v but_o by_o that_o which_o be_v already_o move_v the_o question_n therefore_o about_o the_o magnitude_n and_o beginning_n of_o the_o world_n be_v not_o to_o be_v determine_v by_o philosopher_n but_o by_o those_o that_o be_v lawful_o authorise_v to_o order_v the_o worship_n of_o god_n for_o as_o almighty_a god_n when_o he_o have_v bring_v his_o people_n into_o judaea_n allow_v the_o priest_n the_o first_o fruit_n reserve_v to_o himself_o so_o when_o he_o have_v deliver_v up_o the_o world_n to_o the_o disputation_n of_o man_n it_o be_v his_o pleasure_n that_o
shall_v the_o finger_n be_v take_v away_o to_o make_v way_n for_o the_o descent_n of_o the_o quicksilver_n see_v it_o descend_v into_o the_o vessel_n under_o it_o till_o there_o be_v only_o so_o much_o remain_v within_o the_o cylinder_n as_o may_v fill_v about_o 26_o inch_n of_o the_o same_o and_o thus_o it_o will_v always_o happen_v whatsoever_o be_v the_o cylinder_n provide_v that_o the_o length_n be_v not_o less_o than_o 26_o inch_n from_o whence_o they_o conclude_v that_o the_o cavity_n of_o the_o cylinder_n above_o the_o quicksilver_n remain_v empty_a of_o all_o body_n but_o in_o this_o experiment_n i_o find_v no_o necessity_n at_o all_o of_o vacuum_n for_o when_o the_o quicksilver_n which_o be_v in_o the_o cylinder_n descend_v the_o vessel_n under_o it_o must_v needs_o be_v fill_v to_o a_o great_a height_n and_o consequent_o so_o much_o of_o the_o contiguous_a air_n must_v be_v thrust_v away_o as_o may_v make_v place_n for_o the_o quicksilver_n which_o be_v descend_v now_o if_o 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therefore_o in_o descend_v it_o must_v of_o necessity_n stay_v somewhere_o namely_o there_o where_o its_o endeavour_n downward_o and_o the_o resistance_n of_o the_o same_o to_o the_o penetration_n of_o the_o air_n come_v to_o a_o aequilibrium_fw-la and_o by_o this_o experiment_n it_o be_v manifest_a that_o this_o aequilibrium_fw-la will_v be_v at_o the_o height_n of_o 26_o inch_n or_o thereabouts_o the_o three_o experiment_n be_v that_o when_o a_o vessel_n have_v as_o much_o air_n in_o it_o as_o it_o can_v natural_o contain_v there_o may_v nevertheless_o be_v force_v into_o it_o as_o much_o water_n as_o will_v fill_v three_o quarter_n of_o the_o same_o vessel_n and_o the_o experiment_n be_v make_v in_o this_o manner_n into_o the_o glass_n bottle_n represent_v in_o the_o 2d_o figure_n by_o the_o sphere_n f_o g_o who_o centre_n be_v a_o let_v the_o pipe_n b_o a_o c_o be_v so_o fit_v that_o it_o may_v precise_o fill_v the_o mouth_n of_o the_o bottle_n and_o let_v the_o end_n b_o be_v so_o 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last_o the_o cover_v be_v fasten_v on_o again_o and_o the_o cock_n h_o c_o open_v the_o water_n will_v run_v swift_o out_o at_o e_o and_o sink_v by_o little_a and_o little_a from_o g_z f_o to_o the_o bottom_n of_o the_o pipe_n b._n from_o this_o phaenomenon_n they_o argue_v for_o the_o necessity_n of_o vacuum_n in_o this_o manner_n the_o bottle_n from_o the_o beginning_n be_v full_a of_o air_n which_o air_n can_v neither_o go_v out_o by_o penetrate_v so_o great_a a_o length_n of_o water_n as_o be_v inject_v by_o the_o pipe_n nor_o by_o any_o other_o way_n of_o necessity_n therefore_o all_o the_o water_n as_o high_a as_o f_o g_o as_o also_o all_o the_o air_n that_o be_v in_o the_o bottle_n before_o the_o water_n be_v force_v in_o must_v now_o be_v in_o the_o same_o place_n which_o at_o first_o be_v fill_v by_o the_o air_n alone_o which_o be_v impossible_a if_o all_o the_o space_n within_o the_o bottle_n be_v former_o fill_v with_o air_n precise_o that_o be_v without_o any_o vacuum_n beside_o though_o some_o man_n perhaps_o may_v think_v the_o air_n be_v a_o thin_a body_n may_v pass_v through_o the_o body_n of_o the_o water_n contain_v in_o the_o pipe_n yet_o from_o that_o other_o phaenomenon_n namely_o that_o all_o the_o water_n which_o be_v in_o the_o space_n b_o f_o g_o be_v cast_v out_o again_o by_o the_o spout_n at_o e_o for_o which_o it_o seem_v impossible_a that_o any_o other_o reason_n can_v be_v give_v beside_o the_o force_n by_o which_o the_o air_n free_v itself_o from_o compression_n it_o follow_v that_o either_o there_o be_v in_o the_o bottle_n some_o space_n empty_a or_o that_o many_o body_n may_v be_v together_o in_o the_o same_o place_n but_o this_o last_o be_v absurd_a and_o therefore_o the_o former_a be_v true_a namely_o that_o there_o be_v vacuum_n this_o argument_n be_v infirm_a in_o two_o place_n for_o first_o that_o be_v assume_v which_o be_v not_o to_o be_v grant_v and_o in_o the_o second_o place_n a_o experiment_n be_v bring_v which_o i_o think_v be_v repugnant_a to_o vacuum_n that_o which_o be_v assume_v be_v that_o the_o air_n can_v have_v no_o passage_n out_o through_o the_o pipe_n nevertheless_o we_o see_v daily_o that_o air_n easy_o ascend_v from_o the_o bottom_n to_o the_o superficies_n of_o a_o river_n as_o be_v manifest_a by_o the_o bubble_n that_o rise_v nor_o do_v it_o need_v any_o other_o cause_n to_o give_v it_o this_o motion_n than_o the_o natural_a endeavour_n downward_o of_o the_o water_n why_o therefore_o may_v not_o the_o endeavour_n upward_o of_o the_o same_o water_n acquire_v by_o the_o injection_n which_o endeavour_v upward_o be_v great_a than_o the_o natural_a endeavour_n of_o the_o water_n downward_o cause_v the_o air_n in_o the_o bottle_n to_o penetrate_v in_o like_a manner_n the_o water_n that_o press_v it_o downward_o especial_o see_v the_o water_n as_o it_o rise_v in_o the_o bottle_n do_v so_o press_v the_o air_n that_o be_v above_o it_o as_o that_o it_o generate_v in_o every_o part_n thereof_o a_o endeavour_n towards_o the_o external_a superficies_n of_o the_o pipe_n and_o consequent_o make_v all_o the_o part_n of_o the_o enclose_a air_n to_o tend_v direct_o towards_o the_o passage_n at_o b_o i_o say_v this_o be_v no_o less_o manifest_a then_o that_o he_o air_n which_o rise_v up_o from_o the_o bottom_n of_o a_o river_n shall_v penetrate_v the_o water_n how_o deep_a soever_o it_o be_v werefore_o i_o do_v not_o yet_o see_v any_o cause_n why_o the_o force_n by_o which_o the_o water_n be_v inject_v shall_v not_o at_o the_o same_o time_n eject_v the_o air_n and_o as_o for_o their_o argue_v the_o necessity_n of_o vacuum_n from_o the_o rejection_n of_o the_o water_n in_o the_o first_o place_n suppose_v there_o be_v vacuum_n i_o demand_v by_o what_o principle_n of_o motion_n that_o ejection_n be_v make_v certain_o see_v this_o motion_n be_v from_o within_o outward_o it_o must_v needs_o be_v cause_v by_o some_o agent_n within_o the_o bottle_n that_o be_v to_o say_v by_o the_o air_n itself_o now_o the_o motion_n of_o that_o air_n be_v cause_v by_o the_o rise_n of_o the_o water_n begin_v at_o the_o bottom_n and_o tend_v upward_o whereas_o the_o motion_n by_o which_o it_o eject_v the_o water_n ought_v to_o begin_v above_o and_o tend_v downward_o from_o whence_o therefore_o have_v the_o enclose_a air_n this_o endeavour_n towards_o the_o bottom_n to_o this_o question_n i_o know_v not_o what_o answer_n can_v be_v give_v unless_o it_o be_v say_v that_o the_o air_n descend_v of_o its_o own_o accord_n to_o expel_v the_o water_n which_o because_o it_o be_v absurd_a and_o that_o the_o air_n after_o the_o water_n be_v force_v in_o have_v as_o much_o room_n as_o its_o magnitude_n require_v there_o
will_v remain_v no_o cause_n at_o all_o why_o the_o water_n shall_v be_v force_v out_o wherefore_o the_o assertion_n of_o vacuum_n be_v repugnant_a to_o the_o very_a experiment_n which_o be_v here_o bring_v to_o establish_v it_o many_o other_o phaenomena_n be_v usual_o bring_v for_o vacuum_n as_o those_o of_o weather-glass_n aeolipile_n wind-gun_n etc._n etc._n which_o will_v all_o be_v very_o hard_a to_o be_v salve_v unless_o water_n be_v penetrable_a by_o air_n without_o the_o intermixture_n of_o empty_a space_n but_o now_o see_v air_n may_v with_o no_o great_a endeavour_n pass_v through_o not_o only_a water_n but_o any_o other_o fluid_a body_n though_o never_o so_o stubborn_a as_o quicksilver_n these_o phaenomena_n prove_v nothing_o nevertheless_o it_o may_v in_o reason_n be_v expect_v that_o he_o that_o will_v take_v away_o vacuum_n shall_v without_o vacuum_n show_v we_o such_o cause_n of_o these_o phaenomena_n as_o shall_v be_v at_o least_o of_o equal_a if_o not_o great_a probability_n this_o therefore_o shall_v be_v do_v in_o the_o follow_a discourse_n when_o i_o come_v to_o speak_v of_o these_o phaenomena_n in_o their_o proper_a place_n but_o first_o the_o most_o general_a hypothesis_n of_o natural_a philosophy_n be_v to_o be_v premise_v and_o see_v that_o supposition_n be_v put_v for_o the_o true_a cause_n of_o apparent_a effect_n every_o supposition_n except_o such_o as_o be_v absurd_a must_v of_o necessity_n consist_v of_o some_o suppose_a possible_a motion_n for_o rest_n can_v never_o be_v the_o essicient_a cause_n of_o any_o thing_n &_o motion_n suppose_v body_n movable_a of_o which_o there_o be_v three_o kind_n fluid_a consistent_a and_o mix_v of_o both_o fluid_fw-la be_v those_o who_o part_n may_v by_o very_o weak_a endeavonr_n be_v separate_v from_o one_o another_o and_o consistent_a those_o for_o the_o separation_n of_o who_o part_n great_a force_n be_v to_o be_v apply_v there_o be_v therefore_o degree_n of_o consistency_n which_o degree_n by_o comparison_n with_o more_o or_o less_o consistent_a have_v the_o name_n of_o hardness_n or_o softness_n wherefore_o a_o fluid_a body_n be_v always_o divisible_a into_o body_n equal_o fluid_a as_o quantity_n into_o quantity_n and_o soft_a body_n of_o whatsoever_o degree_n of_o softness_n into_o soft_a body_n of_o the_o same_o degree_n and_o though_o many_o man_n seem_v to_o conceive_v no_o other_o difference_n of_o fluidity_n but_o such_o as_o arise_v from_o the_o different_a magnitude_n of_o the_o part_n in_o which_o sense_n dust_n though_o of_o diamond_n may_v be_v call_v fluid_a yet_o i_o understand_v by_o fluidity_n that_o which_o be_v make_v such_o by_o nature_n equal_o in_o every_o part_n of_o the_o fluid_a body_n not_o as_o dust_n be_v fluid_a for_o so_o a_o house_n which_o be_v fall_v in_o piece_n may_v be_v call_v fluid_fw-la but_o in_o such_o manner_n as_o water_n seem_v fluid_a and_o to_o divide_v itself_o into_o part_n perpetual_o fluid_a and_o this_o be_v well_o understand_v i_o come_v to_o my_o supposition_n 5_o first_o therefore_o i_o suppose_v that_o the_o immense_a space_n which_o we_o call_v the_o world_n be_v the_o aggregate_v of_o all_o body_n which_o be_v either_o consistent_a &_o visible_a as_o the_o earth_n and_o the_o star_n or_o invisible_a as_o the_o small_a atom_n which_o be_v disseminated_a through_o the_o whole_a space_n between_o the_o earth_n and_o the_o star_n and_o last_o that_o most_o fluid_a aether_n which_o so_o fill_v all_o the_o rest_n of_o the_o universe_n as_o that_o it_o leave_v in_o it_o no_o empty_a place_n at_o all_o second_o i_o suppose_v with_o copernicus_n that_o the_o great_a body_n of_o the_o world_n which_o be_v both_o consistent_a and_o permanent_a have_v such_o order_n among_o themselves_o as_o that_o the_o sun_n have_v the_o first_o place_n mercury_n the_o second_o venus_n the_o three_o the_o earth_n with_o the_o moon_n go_v about_o it_o the_o four_o mars_n the_o five_o jupiter_n with_o his_o attendant_n the_o six_o saturn_n the_o seven_o and_o after_o these_o the_o fix_a star_n have_v their_o several_a distance_n from_o the_o sun_n three_o i_o suppose_v that_o in_o the_o sun_n &_o the_o rest_n of_o the_o planet_n there_o be_v and_o always_o have_v be_v a_o simple_a circular_a motion_n four_o i_o suppose_v that_o in_o the_o body_n of_o the_o air_n there_o be_v certain_a other_o body_n intermingle_v which_o be_v not_o fluid_a but_o withal_o that_o they_o be_v so_o small_a that_o they_o be_v not_o preceptible_a by_o sense_n and_o that_o these_o also_o have_v their_o proper_a simple_a motion_n and_o be_v some_o of_o they_o more_o some_o less_o hard_a or_o consistent_a five_o i_o suppose_v with_o kepler_n that_o as_o the_o distance_n between_o the_o sun_n and_o the_o earth_n be_v to_o the_o distance_n between_o the_o moon_n and_o the_o earth_n so_o the_o distance_n between_o the_o moon_n and_o the_o earth_n be_v to_o the_o semidiameter_n of_o the_o earth_n as_o for_o the_o magnitude_n of_o the_o circle_n and_o the_o time_n in_o which_o they_o be_v describe_v by_o the_o body_n which_o be_v in_o they_o i_o will_v suppose_v they_o to_o be_v such_o as_o shall_v seem_v most_o agreeable_a to_o the_o phaenomena_n in_o question_n 6_o the_o cause_n of_o the_o different_a season_n of_o the_o year_n and_o of_o the_o several_a variation_n of_o day_n and_o night_n in_o all_o the_o part_n of_o the_o superficies_n of_o the_o earth_n have_v be_v demonstrate_v first_o by_o copernicus_n and_o since_o by_o kepler_n galilaeus_fw-la and_o other_o from_o the_o supposition_n of_o the_o earth_n diurnal_a revolution_n about_o its_o own_o axis_n together_o with_o its_o annual_a motion_n about_o the_o sun_n in_o the_o ecliptic_a according_a to_o the_o order_n of_o the_o sign_n and_o three_o by_o the_o annual_a revolution_n of_o the_o same_o earth_n about_o its_o own_o centre_n contrary_a to_o the_o order_n of_o the_o sign_n i_o suppose_v with_o copernicus_n that_o the_o diurnal_a revolution_n be_v from_o the_o motion_n of_o the_o earth_n by_o which_o the_o aequinoctial_a circle_n be_v describe_v about_o it_o and_o as_o for_o the_o other_o two_o annual_a motion_n they_o be_v the_o efficient_a cause_n of_o the_o earth_n be_v carry_v about_o in_o the_o ecliptic_a in_o such_o manner_n as_o that_o its_o axis_n be_v always_o keep_v parallel_n to_o itself_o which_o parallelisme_n be_v for_o this_o reason_n introduce_v lest_o by_o the_o earth_n annual_a revolution_n its_o pole_n shall_v seem_v to_o be_v necessary_o carry_v about_o the_o sun_n contrary_a to_o experience_n i_o have_v in_o the_o 10_o artic._n of_o the_o â—â—th_v chap._n demonstrate_v from_o the_o supposition_n of_o simple_a circular_a motion_n in_o the_o sun_n that_o the_o earth_n be_v so_o carry_v about_o the_o sun_n as_o that_o its_o axis_n be_v thereby_o keep_v always_o parallel_v to_o itself_o wherefore_o from_o these_o two_o suppose_a motion_n in_o the_o sun_n the_o one_o simple_a circular_a motion_n the_o other_o circular_a motion_n about_o it_o own_v centre_n it_o may_v be_v demonstrate_v that_o the_o year_n have_v both_o the_o same_o variation_n of_o day_n and_o night_n as_o have_v be_v demonstrate_v by_o copernicus_n for_o if_o the_o circle_n abcd_v in_o the_o 3d_o figure_n be_v the_o ecliptic_a who_o centre_n be_v e_o and_o diameter_n aec_fw-la and_o the_o earth_n be_v place_v in_o a_o &_o the_o sun_n be_v move_v in_o the_o little_a circle_n fghi_fw-la namely_o according_a to_o the_o order_n f_o g_o h_o &_o i_o it_o have_v be_v demonstrate_v that_o a_o body_n place_v in_o a_o will_v be_v move_v in_o the_o same_o order_n through_o the_o point_n of_o the_o ecliptic_a a_o b_o c_o &_o d_o and_o will_v always_o keep_v its_o axis_n parallel_n to_o its_o self_n but_o if_o as_o i_o have_v suppose_v the_o earth_n also_o be_v move_v with_o simple_a circular_a motion_n in_o a_o plain_a that_o pass_v through_o a_o cut_v the_o plain_a of_o the_o ecliptic_a so_o as_o that_o the_o common_a section_n of_o both_o the_o plain_n be_v in_o ac_fw-la thus_o also_o the_o axis_n of_o the_o earth_n will_v be_v keep_v always_o parallel_v to_o itself_o for_o let_v the_o centre_n of_o the_o earth_n be_v move_v about_o in_o the_o circumference_n of_o the_o epicycle_n who_o diameter_n be_v lak_a which_o be_v a_o part_n of_o the_o straight_a line_n lac_fw-la therefore_o lak_a the_o diameter_n of_o the_o epicycle_n pass_v through_o the_o centre_n of_o the_o earth_n will_v be_v in_o the_o plain_a of_o the_o ecliptic_a wherefore_o see_v that_o by_o reason_n of_o the_o earth_n simple_a motion_n both_o in_o the_o ecliptic_a and_o in_o its_o epicycle_n the_o straight_a line_n lak_a be_v keep_v always_o parallel_v to_o itself_o every_o other_o straight_o line_n also_o take_v in_o the_o body_n of_o the_o earth_n and_o consequent_o its_o axis_n will_v in_o like_a manner_n be_v keep_v always_o parallel_v
conversion_n of_o the_o earth_n by_o which_o conversion_n all_o thing_n that_o adhere_v to_o its_o superficies_n be_v necessary_o carry_v about_o with_o it_o may_v be_v refer_v the_o three_o phaenomena_n concern_v the_o tide_n of_o the_o ocean_n whereof_o the_o first_o be_v the_o alternate_a elevation_n and_o depression_n of_o the_o water_n at_o the_o shore_n twice_o in_o the_o space_n of_o 24_o hour_n and_o near_o upon_o 52_o minute_n for_o so_o it_o have_v constant_o continue_v in_o all_o age_n the_o second_o that_o at_o the_o new_a and_o full_a moon_n the_o elevation_n of_o the_o water_n be_v great_a then_o at_o other_o time_n between_o and_o the_o three_o that_o when_o the_o sun_n be_v in_o the_o equinoctial_a they_o be_v yet_o great_a than_o at_o any_o other_o time_n for_o the_o salve_v of_o which_o phaenomena_n we_o have_v already_o the_o four_o abovementioned_a motion_n to_o which_o i_o assume_v also_o this_o that_o the_o part_n of_o the_o earth_n which_o be_v call_v america_n be_v high_a than_o the_o water_n and_o extend_v almost_o the_o space_n of_o a_o whole_a semicircle_n from_o north_n to_o south_n give_v a_o stop_n to_o the_o motion_n of_o the_o water_n this_o be_v grant_v in_o the_o same_o four_o figure_n where_o l_o b_o k_o c_o be_v suppose_v to_o be_v in_o the_o plain_a of_o the_o moon_n monthly_a motion_n let_v the_o little_a circle_n l_o d_o k_o e_o be_v describe_v about_o the_o same_o centre_n a_o in_o the_o plain_a of_o the_o equinoctial_a this_o circle_n therefore_o will_v decline_v from_o the_o circle_n l_o b_o k_o c_o in_o a_o angle_n of_o almost_o 28_o degree_n and_o ½_o for_o the_o great_a declination_n of_o the_o ecliptic_a be_v 23½_n to_o which_o add_v 5_o for_o the_o great_a declination_n of_o the_o moon_n from_o the_o ecliptic_a the_o sum_n will_v be_v 28_o degree_n and_o ½_o see_v now_o the_o water_n which_o be_v under_o the_o circle_n of_o the_o moon_n course_n be_v by_o reason_n of_o the_o earth_n simple_a motion_n in_o the_o plain_a of_o the_o same_o circle_n move_v together_o with_o the_o earth_n that_o be_v to_o say_v together_o with_o their_o own_o bottom_n neither_o out-going_a nor_o outgo_v if_o we_o add_v the_o diurnal_a motion_n by_o which_o the_o other_o water_n which_o be_v under_o the_o equinoctial_a be_v move_v in_o the_o same_o order_n and_o consider_v withal_o that_o the_o circle_n of_o the_o moon_n and_o of_o the_o equinoctial_a intersect_n one_o another_o it_o will_v be_v manifest_a that_o both_o those_o water_n which_o be_v under_o the_o circle_n of_o the_o moon_n and_o under_o the_o equinoctial_a will_v run_v together_o under_o the_o equinoctial_a and_o consequent_o that_o their_o motion_n will_v not_o only_o be_v swift_a than_o the_o ground_n that_o carry_v they_o but_o also_o that_o the_o water_n themselves_o will_v have_v great_a elevation_n whensoever_o the_o earth_n be_v in_o the_o equinoctial_a wherefore_o whatsoever_o the_o cause_n of_o the_o tide_n may_v be_v this_o may_v be_v the_o cause_n of_o their_o augmentation_n at_o that_o time_n again_o see_v i_o have_v suppose_v the_o moon_n to_o be_v carry_v about_o by_o the_o simple_a motion_n of_o the_o earth_n in_o the_o little_a circle_n lbkc_n and_o demonstrate_v at_o the_o 4_o article_n of_o the_o 21_o chapter_n that_o whatsoever_o be_v move_v by_o a_o movent_fw-la that_o have_v simple_a motion_n will_v be_v move_v always_o with_o the_o same_o velocity_n it_o follow_v that_o the_o centre_n of_o the_o earth_n will_v be_v carry_v in_o the_o circumference_n lbkc_n with_o the_o same_o velocity_n with_o which_o the_o moon_n be_v carry_v in_o the_o circumference_n mnop_n wherefore_o the_o time_n in_o which_o the_o moon_n be_v carry_v about_o in_o mnop_n be_v to_o the_o time_n in_o which_o the_o earth_n be_v carry_v about_o in_o lbkc_n as_o one_o circumference_n to_o the_o other_o that_o be_v as_o ao_o to_o ak_v but_o ao_o be_v observe_v to_o be_v to_o the_o semidiameter_n of_o the_o earth_n as_o 59_o to_o 1_o and_o therefore_o the_o earth_n if_o ak_v be_v put_v for_o its_o semidiameter_n will_v make_v 59_o revolution_n in_o lbkc_n in_o the_o time_n that_o the_o moon_n make_v one_o monthly_a circuit_n in_o mnop_n but_o the_o moon_n make_v her_o monthly_a circuit_n in_o little_a more_o than_o 29_o day_n wherefore_o the_o earth_n shall_v make_v its_o circuit_n in_o the_o circumference_n lbkc_n in_o 12_o hour_n and_o a_o little_a more_o namely_o about_o 26_o minute_n more_o that_o be_v to_o say_v it_o shall_v make_v two_o circuit_n in_o 24_o hour_n and_o almost_o 52_o minute_n which_o be_v observe_v to_o be_v the_o time_n between_o the_o high_a water_n of_o one_o day_n and_o the_o high_a water_n of_o the_o day_n follow_v now_o the_o course_n of_o the_o water_n be_v hinder_v by_o the_o southern_a part_n of_o america_n their_o motion_n will_v be_v interrupt_v there_o and_o consequent_o they_o will_v be_v elevate_v in_o those_o place_n and_o sink_v down_o again_o by_o their_o own_o weight_n twice_o in_o the_o space_n of_o 24_o hour_n and_o 52_o minute_n and_o thus_o i_o have_v give_v a_o possible_a cause_n of_o the_o diurnal_a reciprocation_n of_o the_o ocean_n now_o from_o this_o swell_n of_o the_o ocean_n in_o those_o part_n of_o the_o earth_n proceed_v the_o flow_n and_o ebb_n in_o the_o atlantic_a spanish_a british_a and_o german_a sea_n which_o though_o they_o have_v their_o set_a time_n yet_o upon_o several_a shore_n they_o happen_v at_o several_a hour_n of_o the_o day_n and_o they_o receive_v some_o augmentation_n from_o the_o north_n by_o reason_n that_o the_o shore_n of_o china_n and_o tartary_n hinder_v the_o general_a course_n of_o the_o water_n make_v they_o swell_v there_o and_o discharge_v themselves_o in_o part_n through_o the_o straight_a of_o anian_a into_o the_o northern_a ocean_n and_o so_o into_o the_o german_a sea_n as_o for_o the_o spring_n tide_n which_o happen_v at_o the_o time_n of_o the_o new_a &_o full_a moon_n they_o be_v cause_v by_o that_o simple_a motion_n which_o at_o the_o beginning_n i_o suppose_v to_o be_v always_o in_o the_o moon_n for_o as_o when_o i_o show_v the_o cause_n of_o the_o excentricity_n of_o the_o earth_n i_o derive_v the_o elevation_n of_o the_o water_n from_o the_o simple_a motion_n of_o the_o sun_n so_o the_o same_o may_v here_o be_v derive_v from_o the_o simple_a motion_n of_o the_o moon_n for_o though_o from_o the_o generation_n of_o cloud_n there_o appear_v in_o the_o sun_n a_o more_o manifest_a power_n of_o elevate_a the_o water_n then_o in_o the_o moon_n yet_o the_o power_n of_o increase_a moisture_n in_o vegetable_n and_o live_a creature_n appear_v more_o manifest_o in_o the_o moon_n then_o in_o the_o sun_n which_o may_v perhaps_o proceed_v from_o this_o that_o the_o sun_n raise_v up_o great_a and_o the_o moon_n lesser_a drop_n of_o water_n nevertheless_o it_o be_v more_o likely_a and_o more_o agreeable_a to_o common_a observation_n that_o rain_n be_v raise_v not_o only_o by_o the_o sun_n but_o also_o by_o the_o moon_n for_o almost_o all_o man_n expect_v change_v of_o weather_n at_o the_o time_n of_o the_o conjunction_n of_o the_o sun_n and_o moon_n with_o one_o another_o and_o with_o the_o earth_n more_o than_o in_o the_o time_n of_o their_o quarter_n in_o the_o last_o place_n the_o cause_n why_o the_o spring_n tide_n be_v great_a at_o the_o time_n of_o the_o aequinox_n have_v be_v already_o sufficient_o declare_v in_o this_o article_n where_o i_o have_v demonstrate_v that_o the_o two_o motion_n of_o the_o earth_n namely_o its_o simple_a motion_n in_o the_o little_a circle_n lbkc_n and_o its_o diurnal_a motion_n in_o ldke_n cause_n necessary_o a_o great_a elevation_n of_o water_n when_o the_o sun_n be_v about_o the_o aequinox_n then_o when_o he_o be_v in_o other_o place_n i_o have_v therefore_o give_v possible_a cause_n of_o the_o phaenomenon_n of_o the_o flow_v and_o ebb_a of_o the_o ocean_n 11_o as_o for_o the_o explication_n of_o the_o yearly_a praecession_n of_o the_o aequinoctial_a point_n we_o must_v remember_v that_o as_o i_o have_v already_o show_v the_o annual_a motion_n of_o the_o earth_n be_v not_o in_o the_o circumference_n of_o a_o circle_n but_o of_o a_o ellipsis_n or_o a_o line_n not_o considerable_o different_a from_o that_o of_o a_o ellipsis_n in_o the_o first_o place_n therefore_o this_o elliptical_a line_n be_v to_o be_v describe_v let_v the_o ecliptic_a ♎_o ♑_o ♈_o ♋_o in_o the_o 5_o figure_n be_v divide_v into_o four_o equal_a part_n by_o the_o two_o straight_a line_n ab_fw-la and_o ♑_o ♋_o cut_v one_o another_o at_o right_a angle_n in_o the_o centre_n c_o and_o take_v the_o arch_n bd_v of_o 2_o degree_n and_o 16_o minute_n let_v the_o straight_a line_n de_fw-fr be_v draw_v parallel_n to_o ab_fw-la and_o cut_n ♑_o ♋_o in_o f_z
long_o as_o there_o be_v sufficient_a heat_n in_o it_o but_o this_o cease_n it_o will_v shine_v no_o long_o also_o we_o find_v by_o experience_n that_o in_o the_o glow-worm_n there_o be_v a_o certain_a thick_a humour_n like_o the_o crystalline_a humour_n of_o the_o eye_n which_o if_o it_o be_v take_v out_o and_o hold_v long_o enough_o in_o one_o finger_n and_o then_o be_v carry_v into_o the_o dark_a it_o will_v shine_v by_o reason_n of_o the_o warmth_n it_o receive_v from_o the_o finger_n but_o as_o soon_o as_o it_o be_v cold_a it_o will_v cease_v shine_v from_o whence_o therefore_o can_v these_o creature_n have_v their_o light_n but_o from_o lie_v all_o day_n in_o the_o sunshine_n in_o the_o hot_a time_n of_o summer_n in_o the_o same_o manner_n rot_a wood_n except_o it_o grow_v rot_v in_o the_o sunshine_n or_o be_v afterward_o long_o enough_o expose_v to_o the_o sun_n will_v not_o shine_v that_o this_o do_v not_o happen_v in_o every_o worm_n nor_o in_o all_o kind_n of_o rot_a wood_n nor_o in_o all_o calcine_v stone_n the_o cause_n may_v be_v that_o the_o part_n of_o which_o those_o body_n be_v make_v be_v different_a both_o in_o motion_n and_o figure_n from_o the_o part_n of_o body_n of_o other_o kind_n 7_o also_o the_o sea-water_n shine_v when_o it_o be_v either_o dash_v with_o the_o stroke_n of_o oar_n or_o when_o a_o ship_n in_o its_o course_n break_v strong_o through_o it_o but_o more_o or_o less_o according_a as_o the_o wind_n blow_v from_o different_a point_n the_o cause_n whereof_o may_v be_v this_o that_o the_o particle_n of_o salt_n though_o they_o never_o shine_v in_o the_o salt-pit_n where_o they_o be_v but_o slow_o draw_v up_o by_o the_o sun_n be_v here_o beat_v up_o into_o the_o air_n in_o great_a quantity_n and_o with_o more_o force_n be_v withal_o make_v to_o turn_v round_o and_o consequent_o to_o shine_v though_o weak_o i_o have_v therefore_o give_v a_o possible_a cause_n of_o this_o phaenomenon_n 8_o if_o such_o matter_n as_o be_v compound_v of_o hard_a little_a body_n be_v set_v on_o fire_n it_o must_v needs_o be_v that_o as_o they_o fly_v out_o in_o great_a or_o less_o quantity_n the_o flame_n which_o be_v make_v by_o they_o will_v be_v great_a or_o less_o and_o if_o the_o aethereal_a or_o fluid_a part_n of_o that_o matter_n fly_v out_o together_o with_o they_o their_o motion_n will_v be_v the_o swift_a as_o it_o be_v in_o wood_n and_o other_o thing_n which_o flame_n with_o a_o manifest_a mixture_n of_o wind_n when_o therefore_o these_o hard_a particle_n by_o their_o fly_v out_o move_v the_o eye_n strong_o they_o shine_v bright_a and_o a_o great_a quantity_n of_o they_o fly_v out_o together_o they_o make_v a_o great_a shine_a body_n for_o flame_n be_v nothing_o but_o a_o aggregate_v of_o shine_a particle_n the_o great_a the_n aggregate_v be_v the_o great_a and_o more_o manifest_a will_v be_v the_o flame_n i_o have_v therefore_o show_v a_o possible_a cause_n of_o flame_n and_o from_o hence_o the_o cause_n appear_v evident_o 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yet_o there_o will_v be_v in_o the_o part_n a_o endeavour_n to_o simple_a motion_n by_o which_o the_o whole_a body_n will_v either_o be_v melt_v or_o which_o be_v a_o degree_n of_o melt_v soften_v for_o all_o motion_n have_v some_o effect_n upon_o all_o matter_n whatsoever_o as_o have_v be_v show_v at_o the_o 3d_o article_n of_o the_o 16_o chapter_n now_o if_o it_o be_v soften_v to_o such_o a_o degree_n as_o that_o the_o stubborness_n of_o the_o part_n be_v exceed_v by_o their_o gravity_n than_o we_o say_v it_o be_v melt_v otherwise_o soften_v and_o make_v pliant_a and_o ductile_a again_o the_o matter_n have_v in_o it_o some_o particle_n hard_a other_o aethereal_a or_o watery_a if_o by_o the_o application_n of_o fire_n these_o late_a be_v call_v out_o the_o former_a will_n thereby_o come_v to_o a_o more_o full_a contact_n with_o one_o another_o and_o consequent_o will_v not_o be_v so_o easy_o separate_v that_o be_v to_o say_v the_o whole_a body_n will_v be_v make_v hard_a and_o this_o may_v be_v the_o cause_n why_o the_o same_o fire_n make_v some_o thing_n soft_a other_o hard._n 9_o it_o be_v know_v by_o experience_n that_o if_o hay_o be_v lay_v wet_a together_o in_o a_o heap_n it_o will_v after_o a_o time_n begin_v to_o smoke_n and_o then_o burn_v as_o it_o be_v of_o itself_o the_o cause_n whereof_o seem_v to_o be_v this_o that_o in_o the_o air_n which_o be_v enclose_v within_o the_o hay_n there_o be_v those_o little_a body_n which_o as_o i_o have_v suppose_v be_v move_v free_o with_o simple_a motion_n but_o this_o motion_n be_v by_o degree_n hinder_v more_o and_o more_o by_o the_o descend_a moisture_n which_o at_o the_o last_o fill_v and_o stop_v all_o the_o passage_n the_o thin_a part_n of_o the_o air_n ascend_v by_o penetrate_v the_o water_n and_o those_o hard_a little_a bodâ—â—_n be_v so_o thrust_v together_o that_o they_o touch_v and_o press_v one_o another_o acquire_v strong_a motion_n till_o at_o last_o by_o the_o increase_a strength_n of_o this_o motion_n the_o watery_a part_n be_v first_o drive_v outward_o from_o whence_o appear_v vapour_n and_o by_o the_o continue_a increase_n of_o this_o motion_n the_o small_a particle_n of_o the_o dry_a hay_n be_v force_v out_o and_o recover_v their_o natural_a simple_a motion_n they_o grow_v hot_a and_o shine_v that_o be_v to_o say_v they_o be_v set_v on_o fire_n the_o same_o also_o may_v be_v the_o cause_n of_o lightning_n which_o happen_v in_o the_o hot_a time_n of_o the_o year_n when_o the_o water_n be_v raise_v up_o in_o great_a quantity_n and_o carry_v high_a for_o after_o the_o first_o cloud_n be_v raise_v other_o after_o other_o follow_v they_o and_o be_v congeal_v above_o they_o happen_v while_o some_o of_o they_o ascend_v and_o other_o descend_v to_o fall_v upon_o another_o in_o such_o manner_n as_o that_o in_o some_o place_n all_o their_o part_n be_v join_v together_o in_o other_o they_o leave_v hollow_a space_n between_o they_o and_o into_o these_o space_n the_o aethereal_a part_n be_v force_v out_o by_o the_o compressure_n of_o the_o cloud_n many_o of_o the_o hard_a little_a body_n be_v so_o pen_v together_o as_o that_o they_o have_v not_o the_o liberty_n of_o such_o motion_n as_o be_v natural_a to_o the_o air_n wherefore_o their_o endeavour_n grow_v more_o vehement_a till_o at_o last_o they_o force_v their_o way_n through_o the_o cloud_n sometime_o in_o one_o place_n sometime_o in_o another_o and_o break_v through_o with_o great_a noise_n they_o move_v the_o air_n violent_o &_o strike_v our_o eye_n generate_v light_a that_o be_v to_o say_v they_o shine_v and_o this_o shine_v be_v that_o we_o call_v lightning_n 10_o the_o most_o common_a phaenomenon_n proceed_v from_o fire_n and_o yet_o the_o most_o admirable_a of_o all_o other_o be_v the_o force_n of_o gunpowder_n fire_v which_o be_v compound_v of_o niter_n brimstone_n and_o coles_n beat_v small_a have_v from_o the_o coal_n its_o first_o take_v fire_n from_o the_o brimstone_n its_o nourishment_n and_o flame_n that_o be_v to_o say_v light_a and_o motion_n and_o from_o the_o niter_fw-la the_o vehemence_n of_o both_o now_o if_o a_o piece_n of_o niter_n before_o it_o be_v beat_v be_v lay_v upon_o a_o burn_a coal_n first_o it_o melt_v and_o like_o water_n quench_v that_o part_n of_o the_o coal_n it_o touch_v then_o vapour_n or_o air_n fly_v out_o where_o the_o coal_n and_o niter_n join_v blow_v the_o coal_n with_o great_a swiftness_n and_o vehemence_n on_o all_o side_n and_o from_o hence_o it_o come_v to_o pass_v that_o by_o two_o contrary_a motion_n the_o one_o of_o the_o particle_n which_o go_v out_o of_o the_o burn_a coal_n the_o other_o of_o those_o of_o the_o aethereal_a and_o watery_a substance_n
of_o the_o niter_n be_v generate_v that_o vehement_a motion_n and_o inflammation_n and_o last_o when_o there_o be_v no_o more_o action_n from_o the_o niter_fw-la that_o be_v to_o say_v when_o the_o volatile_a part_n of_o the_o niter_n be_v fly_v out_o there_o be_v find_v about_o the_o side_n a_o certain_a white_a substance_n which_o be_v throw_v again_o into_o the_o fire_n will_v grow_v red_a hot_a again_o but_o will_v not_o be_v dissipate_v at_o least_o unless_o the_o fire_n be_v augment_v if_o now_o a_o possible_a cause_n of_o this_o be_v find_v out_o the_o same_o will_v also_o be_v a_o possible_a cause_n why_o a_o grain_n of_o gunpowder_n set_v on_o fire_n do_v expand_v itself_o with_o such_o vehement_a motion_n and_o shine_v and_o it_o may_v be_v cause_v in_o this_o manner_n let_v the_o particle_n of_o which_o niter_n consist_v be_v suppose_v to_o be_v some_o of_o they_o hard_o other_o watery_a and_o the_o rest_n aethereal_a also_o let_v the_o hard_a particle_n be_v suppose_v to_o be_v spherical_o hollow_a like_o small_a bubble_n so_o that_o many_o of_o they_o grow_v together_o may_v constitute_v a_o body_n who_o little_a cavern_n be_v fill_v with_o a_o substance_n which_o be_v either_o watery_a or_o aethereal_a or_o both_o as_o soon_o therefore_o as_o the_o hard_a particle_n be_v dissipate_v the_o watery_a and_o aethereal_a particle_n will_v necessary_o fly_v out_o and_o as_o they_o fly_v of_o necessity_n blow_v strong_o the_o burn_a coal_n and_o brimstone_n which_o be_v mingle_v together_o whereupon_o there_o will_v follow_v a_o great_a expansion_n of_o light_n with_o vehement_a flame_n and_o a_o violent_a dissipation_n of_o the_o particle_n of_o the_o niter_n the_o brimstone_n and_o the_o coal_n wherefore_o i_o have_v give_v a_o possible_a cause_n of_o the_o force_n of_o fire_a gunpowder_n it_o be_v manifest_a from_o hence_o that_o for_o the_o render_n of_o the_o cause_n why_o a_o bullet_n of_o lead_n or_o iron_n shoot_v from_o a_o piece_n of_o ordnance_n fly_v with_o so_o great_a velocity_n there_o be_v no_o necessity_n to_o introduce_v such_o rarefaction_n as_o by_o the_o common_a definition_n of_o it_o make_v the_o same_o matter_n to_o have_v sometime_o more_o sometime_o less_o quantity_n which_o be_v unconceivable_a for_o every_o thing_n be_v say_v to_o be_v great_a or_o less_o as_o it_o have_v more_o or_o less_o quantity_n the_o violence_n with_o which_o a_o bullet_n be_v thrust_v out_o of_o a_o gun_n proceed_v from_o the_o swiftness_n of_o the_o small_a particle_n of_o the_o fire_a powder_n at_o least_o it_o may_v proceed_v from_o that_o cause_n without_o the_o supposition_n of_o any_o empty_a space_n 11_o beside_o by_o the_o attrition_n or_o rub_v of_o one_o body_n against_o another_o as_o of_o wood_n against_o wood_n we_o find_v that_o not_o only_o a_o certain_a degree_n of_o heat_n but_o fire_v itself_o be_v sometime_o generate_v for_o such_o motion_n be_v the_o reciprocation_n of_o pressure_n sometime_o one_o way_n sometime_o the_o other_o and_o by_o this_o reciprocation_n whatsoever_o be_v fluid_a in_o both_o the_o piece_n of_o wood_n be_v force_v hither_o and_o thither_o and_o consequent_o to_o a_o endeavour_n of_o get_v out_o and_o at_o last_o by_o break_v out_o make_v fire_n 12_o now_o light_n be_v distinguish_v into_o first_o second_o third_z and_o so_o on_o infinite_o and_o we_o call_v that_o first_o light_n which_o be_v in_o the_o first_o lucid_a body_n as_o the_o sun_n fire_n etc._n etc._n second_o that_o which_o be_v in_o such_o body_n as_o be_v not_o transparent_a be_v illuminate_v by_o the_o sun_n as_o the_o moon_n a_o wall_n etc._n etc._n and_o three_o that_o which_o be_v in_o body_n not_o transparent_a but_o illuminate_v by_o second_o light_n etc._n etc._n 13_o colour_n be_v light_a but_o trouble_a light_n namely_o such_o as_o be_v generate_v by_o perturb_a motion_n as_o shall_v be_v make_v manifest_a by_o the_o red_a yellow_a blue_a and_o purple_a which_o be_v generate_v by_o the_o 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as_o it_o be_v in_o the_o triangle_n cgk_n which_o be_v near_a to_o the_o first_o light_n the_o transverse_a beam_n make_v greenesse_n and_o when_o the_o same_o second_o light_n be_v weak_a as_o in_o the_o triangle_n ckl_n they_o make_v a_o purple_a colour_n 14_o from_o hence_o may_v be_v deduce_v a_o cause_n why_o the_o moon_n and_o star_n appear_v big_a and_o red_a near_o the_o horizon_n then_o in_o the_o mid-heaven_n for_o between_o the_o eye_n and_o the_o apparent_a horizon_n there_o be_v more_o impure_a air_n such_o as_o be_v mingle_v with_o watery_a and_o earthy_a little_a body_n then_o be_v between_o the_o same_o eye_n and_o the_o more_o elevate_a part_n of_o heaven_n but_o vision_n be_v make_v by_o beam_n which_o constitute_v a_o cone_n who_o base_a if_o we_o look_v upon_o the_o moon_n be_v the_o moon_n face_n and_o who_o vertex_fw-la be_v in_o the_o eye_n and_o therefore_o many_o beam_n from_o the_o moon_n must_v needs_o fall_v upon_o little_a body_n that_o be_v without_o 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to_o powder_n look_v white_a also_o why_o water_n and_o snow_n be_v white_a they_o be_v nothing_o but_o a_o heap_n of_o very_o small_a diaphanous_a body_n namely_o of_o little_a bubble_n from_o who_o several_a convex_a superficies_n there_o be_v by_o reflection_n make_v several_a confuse_a phantasm_n of_o the_o whole_a lucid_a body_n that_o be_v to_o say_v whiteness_n for_o the_o same_o reason_n salt_n and_o nitre_n be_v white_a as_o consist_v of_o small_a bubble_n which_o contain_v within_o they_o water_n and_o aire_n as_o be_v manifest_a in_o nitre_n from_o this_o that_o be_v throw_v into_o the_o fire_n it_o violent_o blow_v the_o same_o which_o salt_n also_o do_v but_o with_o less_o violence_n but_o if_o a_o white_a body_n be_v expose_v not_o to_o the_o light_n of_o the_o day_n but_o to_o that_o of_o the_o fire_n or_o of_o a_o candle_n it_o will_v not_o at_o the_o first_o sight_n be_v easy_o judge_v whether_o it_o be_v white_a or_o yellow_a the_o cause_n whereof_o may_v be_v this_o that_o the_o light_n of_o those_o thing_n which_o burn_v and_o flame_n be_v almost_o of_o a_o middle_a colour_n between_o whiteness_n and_o yellowness_n 16_o as_o whiteness_n be_v light_a so_o blackness_n be_v the_o privation_n of_o light_n or_o darkness_n and_o from_o hence_o it_o be_v first_o that_o all_o holes_n from_o which_o no_o light_n can_v be_v reflect_v to_o the_o eye_n appear_v black_n second_o that_o when_o a_o body_n have_v little_a eminent_a particle_n erect_v straight_o up_o from_o the_o superficies_n so_o that_o the_o beam_n of_o light_n which_o fall_n upon_o they_o be_v reflect_v not_o to_o the_o eye_n but_o to_o the_o body_n itself_o that_o superficies_n appear_v black_a in_o the_o same_o manner_n as_o the_o sea_n appear_v black_a when_o ruffle_v by_o the_o wind._n three_o that_o any_o combustible_a matter_n be_v by_o the_o fire_n make_v to_o look_v black_a before_o it_o shine_v for_o the_o endeavour_n of_o the_o fire_n be_v to_o dissipate_v the_o small_a part_n of_o such_o body_n as_o be_v throw_v into_o it_o it_o must_v first_o raise_v and_o erect_v those_o part_n before_o it_o can_v work_v their_o dissipation_n if_o therefore_o the_o fire_n be_v put_v out_o before_o the_o part_n be_v total_o dissipate_v the_o coal_n will_v appear_v black_a for_o the_o part_n be_v only_o erect_v the_o beam_n of_o light_n fall_v upon_o they_o will_v not_o be_v reflect_v to_o the_o eye_n but_o to_o the_o coal_n itself_o four_o that_o burn_a glass_n do_v more_o easy_o burn_v black_a thing_n then_o white_a for_o in_o a_o white_a superficies_n the_o eminent_a part_n be_v convex_a like_o little_a bubble_n and_o therefore_o the_o beam_n of_o light_n which_o fall_n upon_o they_o be_v reflect_v every_o way_n from_o the_o reflect_a body_n but_o in_o a_o black_a superficies_n where_o the_o eminent_a particle_n be_v more_o erect_v the_o beam_n of_o light_n fall_v upon_o they_o be_v all_o necessary_o reflect_v towards_o the_o body_n itself_o and_o therefore_o body_n that_o be_v black_a be_v more_o easy_o set_v on_o fire_n by_o the_o sunbeam_n than_o those_o that_o be_v white_a five_o that_o all_o colour_n that_o be_v make_v of_o the_o mixture_n of_o white_a and_o black_a proceed_v from_o the_o different_a position_n of_o the_o particle_n that_o rise_v above_o the_o superficies_n and_o their_o different_a form_n of_o asperity_n for_o according_a to_o these_o difference_n more_o or_o few_o beam_n of_o light_n be_v reflect_v from_o several_a body_n to_o the_o eye_n but_o in_o regard_n those_o difference_n be_v innumerable_a and_o the_o body_n themselves_o so_o small_a that_o we_o can_v perceive_v they_o the_o explication_n and_o precise_a determination_n of_o the_o cause_n of_o all_o colour_n be_v a_o thing_n of_o so_o great_a difficulty_n that_o i_o dare_v not_o undertake_v it_o chap._n xxviii_o of_o cold_a wind_n hard_a ice_n restitution_n of_o body_n bend_v diaphanous_a lightning_n and_o thunder_n and_o of_o the_o head_n of_o river_n 1_o why_o breath_n from_o the_o same_o mouth_n sometime_o heat_n and_o sometime_o cool_v 2_o wind_n and_o the_o inconstancy_n of_o wind_n whence_o 3_o why_o there_o be_v a_o constant_a though_o not_o a_o great_a wind_n from_o east_n to_o west_n near_o the_o equator_fw-la 4_o what_o be_v the_o effect_n of_o air_n pen_v in_o between_o the_o cloud_n 5_o no_o change_n from_o soft_a to_o hard_a but_o by_o motion_n 6_o what_o be_v the_o cause_n of_o cold_a near_o the_o pole_n 7_o the_o cause_n of_o ice_n and_o why_o the_o cold_a be_v more_o remiss_a in_o rainy_a then_o in_o clear_a weather_n why_o water_n do_v not_o freeze_v in_o deep_a well_n as_o it_o do_v near_o the_o superficies_n of_o the_o earth_n why_o ice_n be_v not_o so_o heavy_a as_o water_n and_o why_o wine_n be_v not_o so_o easy_o freeze_v
as_o water_n 8_o another_o cause_n of_o hardness_n from_o the_o full_a contact_n of_o atom_n also_o how_o hard_a thing_n be_v break_v 9_o a_o three_o cause_n of_o hardness_n from_o heat_n 10_o a_o four_o cause_n of_o hardness_n from_o the_o motion_n of_o atom_n enclose_v in_o a_o narrow_a space_n 11_o how_o hard_a thing_n be_v soften_v 12_o whence_o proceed_v the_o spontaneous_a restitution_n of_o thing_n bent._n 13_o diaphanous_a and_o opacous_a what_o they_o be_v and_o whence_o 14_o the_o cause_n of_o lightning_n and_o thunder_n 15_o whence_o it_o proceed_v that_o cloud_n can_v fall_v again_o after_o they_o be_v once_o elevate_v and_o freeze_a 16_o how_o it_o can_v be_v that_o the_o moon_n be_v eclipse_v when_o she_o be_v not_o diametral_o opposite_a to_o the_o sun_n 17_o by_o what_o mean_v many_o sun_n may_v appear_v at_o once_o 18_o of_o the_o head_n of_o river_n 1_o as_o when_o the_o motion_n of_o the_o ambient_fw-la aethereal_a substance_n make_v the_o spirit_n and_o fluid_a part_n of_o our_o body_n tend_v outward_o we_o acknowledge_v heat_n so_o by_o the_o endeavour_n inward_o of_o the_o same_o spirit_n and_o humour_n we_o feel_v cold._a so_o that_o to_o cool_v be_v to_o make_v the_o exterior_a part_n of_o the_o body_n endeavour_v inward_o by_o a_o motion_n contrary_n to_o that_o of_o calefaction_n by_o which_o the_o internal_a part_n be_v call_v outward_o he_o therefore_o that_o will_v know_v the_o cause_n of_o cold_a must_v find_v by_o what_o motion_n or_o motion_n the_o exterior_a part_n of_o any_o body_n endeavour_v to_o retire_v inward_o to_o begin_v with_o those_o phaenomena_n which_o be_v the_o most_o familiar_a there_o be_v almost_o no_o man_n but_o know_v that_o breath_n blow_v strong_o and_o which_o come_v from_o the_o mouth_n with_o violence_n that_o be_v to_o say_v the_o passage_n be_v straight_o will_v cool_v the_o hand_n and_o that_o the_o same_o breath_n blow_v gentle_o that_o be_v to_o say_v through_o a_o great_a aperture_n will_v warm_v the_o same_o the_o cause_n of_o which_o phaenomenon_n may_v be_v this_o the_o breath_n go_v out_o have_v two_o motion_n the_o one_o of_o the_o whole_a and_o direct_a by_o which_o the_o foremost_a part_n of_o the_o hand_n be_v drive_v inward_o the_o other_o simple_a motion_n of_o the_o small_a particle_n of_o the_o same_o breath_n which_o as_o i_o have_v show_v in_o the_o 3d_o article_n of_o the_o last_o chapter_n cause_v heat_n according_a therefore_o as_o either_o of_o these_o motion_n be_v predominant_a so_o there_o be_v the_o sense_n sometime_o of_o cold_a sometime_o of_o heat_n wherefore_o when_o the_o breath_n be_v soft_o breathe_v out_o at_o a_o large_a passage_n that_o simple_a motion_n which_o cause_v heat_n prevail_v and_o consequent_o heat_n be_v feel_v and_o when_o by_o compress_v the_o lip_n the_o breath_n be_v more_o strong_o blow_v out_o then_o be_v the_o direct_a motion_n prevalent_a which_o make_v we_o feel_v cold._a for_o the_o direct_a motion_n of_o the_o breath_n or_o air_n be_v wind_n and_o all_o wind_n cool_v or_o diminish_v former_a heat_n 2_o and_o see_v not_o only_o great_a wind_n but_o almost_o any_o ventilation_n and_o stir_v of_o the_o air_n do_v refrigerate_v the_o reason_n of_o many_o experiment_n concern_v cold_a can_v well_o be_v give_v without_o find_v first_o what_o be_v the_o cause_n of_o wind._n now_o wind_n be_v nothing_o else_o but_o the_o direct_a motion_n of_o the_o air_n thrust_v forward_o which_o nevertheless_o when_o many_o wind_n concur_v may_v be_v circular_a or_o otherwise_o indirect_a as_o it_o be_v in_o whirlwind_n wherefore_o in_o the_o first_o place_n we_o be_v to_o inquire_v into_o the_o cause_n of_o wind_n wind_n be_v aire_n move_v in_o a_o considerable_a quantity_n and_o that_o either_o in_o the_o manner_n of_o wave_n which_o be_v both_o forward_o &_o also_o up_o &_o down_o or_o else_o forward_o only_a suppose_v therefore_o the_o air_n both_o clear_a and_o calm_a for_o any_o time_n how_o little_a soever_o yet_o the_o great_a body_n of_o the_o world_n be_v so_o dispose_v and_o order_v as_o have_v be_v say_v it_o will_v be_v necessary_a that_o a_o wind_n present_o arise_v some_o where_o for_o see_v that_o motion_n of_o the_o part_n of_o the_o air_n which_o be_v make_v by_o the_o simple_a motion_n of_o the_o sun_n in_o his_o own_o epicycle_n cause_v a_o exhalation_n of_o the_o particle_n of_o water_n from_o the_o sea_n and_o all_o other_o moist_a body_n and_o those_o particle_n make_v cloud_n it_o must_v needs_o follow_v that_o while_o the_o particle_n of_o water_n pass_v upward_o the_o particle_n of_o air_n for_o the_o keep_n of_o all_o space_n full_a be_v justle_v out_o on_o every_o side_n and_o urge_v the_o next_o particle_n and_o these_o the_o next_o till_o have_v make_v their_o circuit_n there_o come_v continual_o so_o much_o air_n to_o the_o hinder_a part_n of_o the_o earth_n as_o there_o go_v water_n from_o before_o it_o wherefore_o the_o ascend_a vapour_n move_v the_o air_n towards_o the_o side_n every_o way_n and_o all_o direct_a motion_n of_o the_o air_n be_v wind_n they_o make_v a_o wind._n and_o if_o this_o wind_n meet_v often_o with_o other_o vapour_n which_o arise_v in_o other_o place_n it_o be_v manifest_a that_o the_o force_n thereof_o will_v be_v augment_v &_o the_o way_n or_o course_n of_o it_o change_v beside_o according_a as_o the_o earth_n by_o its_o diurnal_a motion_n turn_v sometime_o the_o dry_a sometime_o the_o moist_a part_n towards_o the_o sun_n so_o sometime_o a_o great_a sometime_o a_o less_o quantity_n of_o vapour_n will_v be_v raise_v that_o be_v to_o say_v sometime_o there_o will_v be_v a_o less_o sometime_o a_o great_a wind._n wherefore_o i_o have_v render_v a_o possible_a cause_n of_o such_o wind_n as_o be_v generate_v by_o vapour_n and_o also_o of_o their_o inconstancy_n from_o hence_o it_o follow_v that_o these_o wind_n can_v be_v make_v in_o any_o place_n which_o be_v high_o than_o that_o to_o which_o vapour_n may_v ascend_v nor_o be_v that_o incredible_a which_o be_v report_v of_o the_o high_a mountain_n as_o the_o pique_n of_o tenariffe_n and_o the_o andes_n of_o peru_n namely_o that_o they_o be_v not_o at_o all_o trouble_a with_o these_o inconstant_a wind_n and_o if_o it_o be_v certain_a that_o neither_o rain_n nor_o snow_n be_v ever_o see_v in_o the_o high_a top_n of_o those_o mountain_n it_o can_v not_o be_v doubt_v but_o that_o they_o be_v high_a than_o any_o place_n to_o which_o vapour_n use_v to_o ascend_v 3_o nevertheless_o there_o may_v be_v wind_n there_o though_o not_o that_o which_o be_v make_v by_o the_o ascent_n of_o vapour_n yet_o a_o less_o &_o more_o constant_a wind_n like_o the_o continue_a blast_n of_o a_o pair_n of_o bellows_o blow_v from_o the_o east_n and_o this_o may_v have_v a_o double_a cause_n the_o one_o the_o diurnal_a mo_z tion_n of_o the_o earth_n the_o other_o its_o simple_a motion_n in_o its_o own_o epicycle_n for_o these_o mountain_n be_v by_o reason_n of_o their_o height_n more_o eminent_a than_o all_o the_o rest_n of_o the_o part_n of_o the_o earth_n do_v by_o both_o these_o motion_n drive_v the_o air_n from_o the_o west_n eastward_n to_o which_o though_o the_o diurnal_a motion_n contribute_v but_o little_a yet_o see_v i_o have_v suppose_v that_o the_o simple_a motion_n of_o the_o earth_n in_o its_o own_o epicycle_n make_v two_o revolution_n in_o the_o same_o time_n in_o which_o the_o diurnal_a motion_n make_v but_o one_o and_o that_o the_o semidiameter_n of_o the_o epicycle_n be_v double_a to_o the_o semidiameter_n of_o the_o diurnal_a conversion_n the_o motion_n of_o every_o point_n of_o the_o earth_n in_o its_o own_o epicycle_n will_v have_v its_o velocity_n quadruple_a to_o that_o of_o the_o diurnal_a motion_n so_o that_o by_o both_o these_o motion_n together_o the_o top_n of_o those_o hill_n will_v sensible_o be_v move_v against_o the_o air_n and_o consequent_o a_o wind_n will_v be_v feel_v for_o whether_o the_o air_n strike_v the_o sentient_a or_o the_o sentient_a the_o air_n the_o perception_n of_o motion_n will_v be_v the_o same_o but_o this_o wind_n see_v it_o be_v not_o cause_v by_o the_o ascent_n of_o vapour_n must_v necessary_o be_v very_o constant._n 4_o when_o one_o cloud_n be_v already_o ascend_v into_o the_o air_n if_o another_o cloud_n ascend_v towards_o it_o that_o part_n of_o the_o air_n which_o be_v intercept_v between_o they_o both_o must_v of_o necessity_n be_v press_v out_o every_o way_n also_o when_o both_o of_o they_o while_o the_o one_o ascend_v and_o the_o other_o either_o stay_v or_o descend_v come_v to_o be_v join_v in_o such_o manner_n as_o that_o the_o aethereal_a substance_n be_v shut_v within_o they_o on_o every_o side_n it_o will_v by_o this_o compression_n also_o go_v out_o by_o penetrate_v the_o water_n
but_o in_o the_o mean_a time_n the_o hard_a particle_n which_o be_v mingle_v with_o the_o air_n and_o be_v agitate_a as_o i_o have_v suppose_v with_o simple_a motion_n will_v not_o pass_v through_o the_o water_n of_o the_o cloud_n but_o be_v more_o straight_o compress_v within_o their_o cavity_n and_o this_o i_o have_v demonstrate_v at_o the_o four_o and_o 5_o article_n of_o the_o 22th_o chapter_n beside_o see_v the_o globe_n of_o the_o earth_n float_v in_o the_o air_n which_o be_v agitate_a by_o the_o sun_n motion_n the_o part_n of_o the_o air_n resist_v by_o the_o earth_n will_v spread_v themselves_o every_o way_n upon_o the_o earth_n superficies_n as_o i_o have_v show_v at_o the_o 8_o article_n of_o the_o 21th_o chapter_n 5_o we_o perceive_v a_o body_n to_o be_v hard_a from_o this_o that_o when_o touch_v it_o we_o will_v thrust_v forward_o that_o part_n of_o the_o same_o which_o we_o touch_v we_o can_v do_v it_o otherwise_o then_o by_o thrust_v forward_o the_o whole_a body_n we_o may_v indeed_o easy_o and_o sensible_o thrust_v forward_o any_o particle_n of_o the_o air_n or_o water_n which_o we_o touch_v whilst_o yet_o the_o rest_n of_o its_o part_n remain_v to_o sense_n unmoved_a but_o we_o can_v do_v so_o to_o any_o part_n of_o a_o stone_n wherefore_o i_o define_v a_o hard_a body_n to_o be_v that_o whereof_o no_o part_n can_v be_v sensible_o move_v unless_o the_o whole_a be_v move_v whatsoever_o therefore_o be_v soft_a or_o fluid_a the_o same_o can_v never_o be_v make_v hard_o but_o by_o such_o motion_n as_o make_v many_o of_o the_o part_n together_o stop_v the_o motion_n of_o some_o one_o part_n by_o resist_v the_o same_o 6_o these_o thing_n premise_v i_o shall_v show_v a_o possible_a cause_n why_o there_o be_v great_a cold_a near_o the_o pole_n of_o the_o earth_n then_o further_o from_o they_o the_o motion_n of_o the_o sun_n between_o the_o tropic_n drive_v the_o air_n towards_o that_o part_n of_o the_o earth_n superficies_n which_o be_v perpendicular_o under_o it_o make_v it_o spread_v itself_o every_o way_n and_o the_o velocity_n of_o this_o expansion_n of_o the_o air_n grow_v great_a and_o great_a as_o the_o superficies_n of_o the_o earth_n come_v to_o be_v more_o and_o more_o straighten_v that_o be_v to_o say_v as_o the_o circle_n which_o be_v parallel_v to_o the_o aequator_fw-la come_v to_o be_v less_o and_o less_o wherefore_o this_o expansive_a motion_n of_o the_o air_n drive_v before_o it_o the_o part_n of_o the_o air_n which_o be_v in_o its_o way_n continual_o towards_o the_o pole_n more_o and_o more_o strong_o as_o its_o force_n come_v to_o be_v more_o and_o more_o unite_a that_o be_v to_o say_v as_o the_o circle_n which_o be_v parallel_v to_o the_o aequator_fw-la be_v less_o and_o less_o that_o be_v so_o much_o the_o more_o by_o how_o much_o they_o be_v near_o to_o the_o pole_n of_o the_o earth_n in_o those_o place_n therefore_o which_o be_v near_a to_o the_o pole_n there_o be_v great_a cold_a then_o in_o those_o which_o be_v more_o remote_a from_o they_o now_o this_o expansion_n of_o the_o air_n upon_o the_o superficies_n of_o the_o earth_n from_o east_n to_o west_n do_v by_o reason_n of_o the_o sun_n perpetual_a accession_n to_o the_o place_n which_o be_v successive_o under_o it_o make_v it_o cold_a at_o the_o time_n of_o the_o sun_n rise_v and_o set_v but_o as_o the_o sun_n come_v to_o be_v continual_o more_o and_o more_o perpendicular_a to_o those_o cool_v place_n so_o by_o the_o heat_n which_o be_v generate_v by_o the_o superven_a simple_a motion_n of_o the_o sun_n that_o cold_a be_v again_o remit_v and_o can_v never_o be_v great_a because_o the_o action_n by_o the_o which_o it_o be_v generate_v be_v not_o permanent_a wherefore_o i_o have_v render_v a_o possible_a cause_n of_o cold_a in_o those_o place_n that_o be_v near_o the_o pole_n or_o where_o the_o obliquity_n of_o the_o sun_n be_v great_a 7_o how_o water_n may_v be_v congeal_v by_o cold_a may_v be_v explain_v in_o this_o manner_n let_v a_o in_o the_o first_o figure_n represent_v the_o sun_n and_o b_o the_o earth_n a_o will_v therefore_o be_v much_o great_a than_o b._n let_v of_o be_v in_o the_o plain_a of_o the_o equinoctial_a to_o which_o let_v gh_a ik_fw-mi and_o lc_n be_v parallel_n last_o let_v c_o and_o d_o be_v the_o pole_n of_o the_o earth_n the_o air_n therefore_o by_o its_o action_n in_o those_o parallel_n will_v rake_v the_o superficies_n of_o the_o earth_n and_o that_o with_o motion_n so_o much_o the_o strong_a by_o how_o much_o the_o parallel_a circle_n towards_o the_o pole_n grow_v less_o and_o less_o from_o whence_o must_v arise_v a_o wind_n which_o will_v force_v together_o the_o uppermost_a part_n of_o the_o water_n and_o withal_o raise_v they_o a_o little_a weaken_v their_o endeavour_n towards_o the_o centre_n of_o the_o earth_n and_o from_o their_o endeavour_n towards_o the_o centre_n of_o the_o earth_n join_v with_o the_o endeavour_n of_o the_o say_a wind_n the_o uppermost_a part_n of_o the_o water_n will_v be_v press_v together_o and_o coagulate_v that_o be_v to_o say_v the_o top_n of_o the_o water_n will_v be_v skin_v over_o and_o harden_v and_o so_o again_o the_o water_n next_o the_o top_n will_v be_v harden_v in_o the_o same_o manner_n till_o at_o length_n the_o ice_n be_v thick_a and_o this_o ice_n be_v now_o compact_v of_o little_a hard_a body_n must_v also_o contain_v many_o particle_n of_o air_n receive_v into_o it_o as_o river_n and_o sea_n so_o also_o in_o the_o same_o manner_n may_v the_o cloud_n be_v freeze_v for_o when_o by_o the_o ascend_a and_o descend_v of_o several_a cloud_n at_o the_o same_o time_n the_o air_n intercept_v between_o they_o be_v by_o compression_n force_v out_o it_o rake_n &_o by_o little_a &_o little_o harden_v they_o and_o though_o those_o small_a drop_n which_o usual_o make_v cloud_n be_v not_o yet_o unite_v into_o great_a body_n yet_o the_o same_o wind_n will_v be_v make_v &_o by_o it_o as_o water_n be_v congeal_v into_o ice_n so_o will_v vapour_n in_o the_o same_o manner_n be_v congeal_v into_o snow_n from_o the_o same_o cause_n it_o be_v that_o ice_n may_v be_v make_v by_o art_n and_o that_o not_o far_o from_o the_o fire_n for_o it_o be_v do_v by_o the_o mingle_n of_o snow_n and_o salt_n together_o and_o by_o bury_v in_o it_o a_o small_a vessel_n full_a of_o water_n now_o while_o the_o snow_n and_o salt_n which_o have_v in_o they_o a_o great_a deal_n of_o air_n be_v melt_v the_o air_n which_o be_v press_v out_o every_o way_n in_o wind_n rake_n the_o side_n of_o the_o vessel_n and_o as_o the_o wind_n by_o its_o motion_n rake_n the_o vessel_n so_o the_o vessel_n by_o the_o same_o motion_n and_o action_n congeles_fw-la the_o water_n within_o it_o we_o find_v by_o experience_n that_o cold_a be_v always_o more_o remiss_a in_o place_n where_o it_o rain_v or_o where_o the_o weather_n be_v cloudy_a thing_n be_v alike_o in_o all_o other_o respect_n then_o where_o the_o air_n be_v clear_a and_o this_o agree_v very_o well_o with_o what_o i_o have_v say_v before_o for_o in_o clear_a weather_n the_o course_n of_o the_o wind_n which_o as_o i_o say_v even_o now_o rake_n the_o superficies_n of_o the_o earth_n as_o it_o be_v free_a from_o all_o interruption_n so_o also_o it_o be_v very_o strong_a but_o when_o small_a drop_n of_o water_n be_v either_o rise_n or_o fall_v that_o wind_n be_v repel_v break_v and_o dissipate_v by_o they_o and_o the_o less_o the_o wind_n be_v the_o less_o be_v the_o cold._n we_o find_v also_o by_o experience_n that_o in_o deep_a well_n the_o water_n freeze_v not_o so_o much_o as_o it_o do_v upon_o the_o superficies_n of_o the_o earth_n for_o the_o wind_n by_o which_o ice_n be_v make_v enter_v into_o the_o earth_n by_o reason_n of_o the_o laxity_n of_o its_o part_n more_o or_o less_o lose_v some_o of_o its_o force_n though_o not_o much_o so_o that_o if_o the_o well_o be_v not_o deep_a it_o will_v freeze_v whereas_o if_o it_o be_v so_o deep_a as_o that_o the_o wind_n which_o cause_v cold_a can_v reach_v it_o it_o will_v not_o freeze_v we_o find_v moreover_o by_o experience_n that_o ice_n be_v light_a than_o water_n the_o cause_n whereof_o be_v manifest_a from_o that_o which_o i_o have_v already_o show_v namely_o that_o air_n be_v receive_v in_o and_o mingle_v with_o the_o particle_n of_o the_o water_n while_o it_o be_v in_o congeling_n 8_o we_o have_v see_v one_o way_n of_o make_v thing_n hard_a namely_o by_o congelation_n another_o way_n be_v thus_o have_v already_o suppose_v that_o innumerable_a atom_n some_o hard_a than_o other_o and_o that_o have_v several_a simple_a motion_n of_o their_o own_o be_v intermingle_v with_o the_o aethereal_a substance_n
not_o a_o sufficient_a cause_n of_o their_o future_a motion_n there_o be_v no_o other_o cause_n of_o motion_n but_o motion_n the_o cause_n therefore_o of_o such_o restitution_n be_v in_o the_o part_n of_o the_o steel_n itself_o wherefore_o while_o it_o remain_v bend_v there_o be_v in_o the_o part_n of_o which_o it_o consist_v some_o motion_n though_o invisible_a that_o be_v to_o say_v some_o endeavour_n at_o least_o that_o way_n by_o which_o the_o restitution_n be_v to_o be_v make_v and_o therefore_o this_o endeavour_n of_o all_o the_o part_n together_o be_v the_o first_o beginning_n of_o restitution_n so_o that_o the_o impediment_n be_v remove_v that_o be_v to_o say_v the_o force_n by_o which_o it_o be_v hold_v bend_v it_o will_v be_v restore_v again_o now_o the_o motion_n of_o the_o part_n by_o which_o this_o be_v do_v be_v that_o which_o i_o call_v simple_a motion_n or_o motion_n return_v into_o itself_o when_o therefore_o in_o the_o bend_n of_o a_o plate_n the_o end_n be_v draw_v together_o there_o be_v on_o one_o side_n a_o mutual_a compression_n of_o the_o part_n which_o compression_n be_v one_o endeavour_v opposite_a to_o another_o endeavour_n and_o on_o the_o other_o side_n a_o divulsion_n of_o the_o part_n the_o endeavour_n therefore_o of_o the_o part_n on_o one_o side_n tend_v to_o the_o restitution_n of_o the_o plate_n from_o the_o middle_n towards_o the_o end_n and_o on_o the_o other_o side_n from_o the_o end_n towards_o the_o middle_n wherefore_o the_o impediment_n be_v take_v away_o this_o endeavour_n which_o be_v the_o begin_n of_o restitution_n will_v restore_v the_o plate_n to_o its_o former_a posture_n and_o thus_o i_o have_v give_v a_o possible_a cause_n why_o some_o body_n when_o they_o be_v bend_v restore_v themselves_o again_o which_o be_v to_o be_v do_v as_o for_o stone_n see_v they_o be_v make_v by_o the_o accretion_n of_o many_o very_a hard_a particle_n within_o the_o earth_n which_o particle_n have_v no_o great_a coherence_n that_o be_v to_o say_v touch_v one_o another_o in_o small_a latitude_n and_o consequent_o admit_v many_o particle_n of_o air_n it_o must_v needs_o be_v that_o in_o bend_v of_o they_o their_o internal_a part_n will_v not_o easy_o be_v compress_v by_o reason_n of_o their_o hardness_n and_o because_o their_o coherence_n be_v not_o firm_a as_o soon_o as_o the_o external_a hard_a particle_n be_v disjoin_v the_o aethereal_a part_n will_v necessary_o break_v out_o and_o so_o the_o body_n will_v sudden_o be_v break_v 13_o those_o body_n be_v call_v diaphanous_a upon_o which_o while_o the_o beam_n of_o a_o lucid_a body_n do_v work_n the_o action_n of_o every_o one_o of_o those_o beam_n be_v propagate_v in_o they_o in_o such_o manner_n as_o that_o they_o still_o retain_v the_o same_o order_n among_o themselves_o or_o the_o inversion_n of_o that_o order_n and_o therefore_o body_n which_o be_v perfect_o diaphanous_a be_v also_o perfect_o homogeneous_a on_o the_o contrary_a a_o opacous_a body_n be_v that_o which_o by_o reason_n of_o its_o heterogeneous_a nature_n do_v by_o innumerable_a reflection_n and_o refraction_n in_o particle_n of_o different_a figure_n and_o unequal_a hardness_n weaken_v the_o beam_n that_o fall_v upon_o it_o before_o they_o reach_v the_o eye_n and_o of_o diaphanous_a body_n some_o be_v make_v such_o by_o nature_n from_o the_o beginning_n as_o the_o substance_n of_o the_o air_n and_o of_o the_o water_n and_o perhaps_o also_o some_o part_n of_o stone_n unless_o these_o also_o be_v water_n that_o have_v be_v long_o congeal_v other_o be_v make_v so_o by_o the_o power_n of_o heat_n which_o congregate_n homogeneon_n body_n but_o such_o as_o be_v make_v diaphanous_a in_o this_o manner_n consist_v of_o part_n which_o be_v former_o diaphanous_a 14_o in_o what_o manner_n cloud_n be_v make_v by_o the_o motion_n of_o the_o sun_n elevate_a the_o particle_n of_o water_n from_o the_o sea_n and_o other_o moist_a place_n have_v be_v explain_v in_o the_o 26_o chapter_n also_o how_o cloud_n come_v to_o be_v freeze_v have_v be_v show_v above_o at_o the_o seven_o article_n now_o from_o this_o that_o air_n may_v be_v enclose_v as_o it_o be_v in_o cavern_n and_o pen_v together_o more_o and_o more_o by_o the_o meeting_n of_o ascend_v and_o descend_v cloud_n may_v be_v deduce_v a_o possible_a cause_n of_o thunder_n and_o lightning_n for_o see_v the_o air_n consist_v of_o two_o part_n the_o one_o aethereal_a which_o have_v no_o proper_a motion_n of_o its_o own_o as_o be_v a_o thing_n divisible_a into_o the_o least_o part_n the_o other_o hard_o namely_o consist_v of_o many_o hard_a atom_n which_o have_v every_o one_o of_o they_o a_o very_a swift_a simple_a motion_n of_o its_o own_o while_o the_o cloud_n by_o their_o meeting_n do_v more_o and_o more_o straighten_v such_o cavity_n as_o they_o intercept_v the_o aethereal_a part_n will_v penetrate_v and_o pass_v through_o their_o watery_a substance_n but_o the_o hard_a part_n will_v in_o the_o mean_a time_n be_v the_o more_o thrust_v together_o and_o press_v one_o another_o and_o consequent_o by_o reason_n of_o their_o vehement_a motion_n they_o will_v have_v a_o endeavour_n to_o rebound_v from_o each_o other_o whensoever_o therefore_o the_o compression_n be_v great_a enough_o and_o the_o concave_a part_n of_o the_o cloud_n be_v for_o the_o cause_n i_o have_v already_o give_v congeal_v into_o ice_n the_o cloud_n will_v necessary_o be_v break_v &_o this_o break_n of_o the_o cloud_n produce_v the_o first_o clap_n of_o thunder_n afterward_o the_o air_n which_o be_v pen_v in_o have_v now_o break_v through_o make_v a_o concussion_n of_o the_o air_n without_o and_o from_o hence_o proceed_v the_o roar_a and_o murmur_n which_o follow_v and_o both_o the_o first_o clap_n and_o the_o murmur_n that_o follow_v it_o make_v that_o noise_n which_o be_v call_v thunder_n also_o from_o the_o same_o air_n break_v through_o the_o cloud_n and_o with_o concussion_n fall_v upon_o the_o eye_n proceed_v that_o action_n upon_o our_o eye_n which_o cause_v in_o we_o a_o perception_n of_o that_o light_n which_o we_o call_v lightning_n wherefore_o i_o have_v give_v a_o possible_a cause_n of_o thunder_n and_o lightning_n 15_o but_o if_o the_o vapour_n which_o be_v raise_v into_o cloud_n do_v run_v together_o again_o into_o water_n or_o be_v congeal_v into_o ice_n from_o whence_o be_v it_o see_v both_o ice_n and_o water_n be_v heavy_a that_o they_o be_v sustain_v in_o the_o air_n or_o rather_o what_o may_v the_o cause_n be_v that_o be_v once_o elevate_v they_o fall_v down_o again_o for_o there_o be_v no_o doubt_n but_o the_o same_o force_n which_o can_v carry_v up_o that_o water_n can_v also_o sustain_v it_o there_o why_o therefore_o be_v once_o carry_v up_o do_v it_o fall_v again_o i_o say_v it_o proceed_v from_o the_o same_o simple_a motion_n of_o the_o sun_n both_o that_o vapour_n be_v force_v to_o ascend_v and_o that_o water_n gather_v into_o cloud_n be_v force_v to_o descend_v for_o in_o the_o 21th_o chapter_n and_o 11_o article_n i_o have_v show_v how_o vapour_n be_v elevate_v and_o in_o the_o same_o chapter_n and_o 5_o article_n i_o have_v also_o show_v how_o by_o the_o same_o motion_n homogeneous_a body_n be_v congregat_v &_o heterogeneous_a dissipate_v that_o be_v to_o say_v how_o such_o thing_n as_o have_v a_o like_a nature_n to_o that_o of_o the_o earth_n be_v drive_v towards_o the_o earth_n that_o be_v to_o say_v what_o be_v the_o cause_n of_o the_o descent_n of_o heavy_a body_n now_o if_o the_o action_n of_o the_o sun_n be_v hinder_v in_o the_o raise_n of_o vapour_n and_o be_v not_o at_o all_o hinder_v in_o the_o cast_n of_o they_o down_o the_o water_n will_v descend_v but_o a_o cloud_n can_v hinder_v the_o action_n of_o the_o sun_n in_o make_v thing_n of_o a_o earthly_a nature_n descend_v to_o the_o earth_n though_o it_o may_v hinder_v it_o in_o make_v vapour_n ascend_v for_o the_o low_a part_n of_o a_o thick_a cloud_n be_v so_o cover_v by_o its_o upper_a part_n as_o that_o it_o can_v receive_v that_o action_n of_o the_o sun_n by_o which_o vapour_n be_v carry_v up_o because_o vapour_n be_v raise_v by_o the_o perpetual_a fermentation_n of_o the_o air_n or_o by_o the_o separate_n of_o its_o small_a part_n from_o one_o another_o which_o be_v much_o weak_a when_o he_o thick_a cloud_n be_v interpose_v then_o when_o the_o sky_n be_v clear_a and_o therefore_o whensoever_o a_o cloud_n be_v make_v thick_a enough_o the_o water_n which_o will_v not_o descend_v before_o will_v then_o descend_v unless_o it_o be_v keep_v up_o by_o the_o agitation_n of_o the_o wind_n wherefore_o i_o have_v render_v a_o possible_a cause_n both_o why_o the_o cloud_n may_v be_v sustain_v in_o the_o air_n and_o also_o why_o they_o may_v fall_v down_o again_o to_o the_o earth_n which_o be_v propound_v to_o
hearer_n the_o sound_n will_v come_v strong_a than_o it_o will_v do_v through_o the_o open_a air_n and_o the_o cause_n not_o only_o the_o possible_a but_o the_o certain_a and_o manifest_a cause_n be_v this_o that_o the_o air_n which_o be_v move_v by_o the_o first_o breath_n and_o carry_v forward_o in_o the_o trunk_n be_v not_o diffuse_v as_o it_o will_v be_v in_o the_o open_a air_n and_o be_v consequent_o bring_v to_o the_o ear_n almost_o with_o the_o same_o velocity_n with_o which_o it_o be_v first_o breathe_v out_o whereas_o in_o the_o open_a air_n the_o first_o motion_n diffuse_v itself_o every_o way_n into_o circle_n such_o as_o be_v make_v by_o the_o throw_n of_o a_o stone_n into_o a_o stand_a water_n where_o the_o velocity_n grow_v less_o and_o less_o as_o the_o undulation_n proceed_v further_a and_o further_o from_o the_o begin_n of_o its_o motion_n the_o second_o be_v this_o that_o if_o the_o trunk_n be_v short_a and_o the_o end_n which_o be_v apply_v to_o the_o mouth_n be_v wide_a than_o that_o which_o be_v apply_v to_o the_o ear_n thus_o also_o the_o sound_n will_v be_v strong_a than_o if_o it_o be_v make_v in_o the_o open_a air_n and_o the_o cause_n be_v the_o same_o namely_o that_o by_o how_o much_o the_o wide_a end_n of_o the_o trunk_n be_v less_o distant_a from_o the_o begin_n of_o the_o sound_n by_o so_o much_o the_o less_o be_v the_o diffusion_n the_o three_o that_o it_o be_v easy_a for_o one_o that_o be_v within_o a_o chamber_n to_o hear_v what_o be_v speak_v without_o then_o for_o he_o that_o stand_v without_o to_o hear_v what_o be_v speak_v within_o for_o the_o window_n and_o other_o inlet_n of_o the_o move_v air_n be_v as_o the_o wide_a end_n of_o the_o trunk_n and_o for_o this_o reason_n some_o creature_n seem_v to_o hear_v the_o better_a because_o nature_n have_v bestow_v upon_o they_o wide_o and_o capacious_a ear_n the_o four_o be_v this_o that_o though_o he_o which_o stand_v upon_o the_o sea_n shore_n can_v hear_v the_o collision_n of_o the_o two_o near_a wave_n yet_o neverthess_n he_o hear_v the_o roar_n of_o the_o whole_a sea_n and_o the_o cause_n seem_v to_o be_v this_o that_o though_o the_o several_a collision_n move_v the_o organ_n yet_o they_o be_v not_o several_o great_a enough_o to_o cause_v sense_n whereas_o nothing_o hinder_v but_o that_o all_o of_o they_o together_o may_v make_v sound_a 3_o that_o body_n when_o they_o be_v strike_v do_v yield_v some_o a_o more_o grave_a other_o a_o more_o acute_a sound_n the_o cause_n may_v consist_v in_o the_o difference_n of_o the_o time_n in_o which_o the_o part_n strike_v and_o force_v out_o of_o their_o place_n return_v to_o the_o same_o place_n again_o for_o in_o some_o body_n the_o restitution_n of_o the_o move_v part_n be_v quick_a in_o other_o slow_a and_o this_o also_o may_v be_v the_o cause_n why_o the_o part_n of_o the_o organ_n which_o be_v move_v by_o the_o medium_fw-la return_v to_o their_o rest_n again_o sometime_o soon_o sometime_o late_a now_o by_o how_o much_o the_o vibration_n or_o the_o reciprocal_a motion_n of_o the_o part_n be_v more_o frequent_a by_o so_o much_o do_v the_o whole_a sound_n make_v at_o the_o same_o time_n by_o one_o stroke_n consist_v of_o more_o and_o consequent_o of_o small_a part_n for_o what_o be_v acute_a in_o sound_n the_o same_o be_v subtle_a in_o matter_n and_o both_o of_o they_o namely_o acute_a sound_n and_o subtle_a matter_n consist_v of_o very_o small_a part_n that_o of_o time_n and_o this_o of_o the_o matter_n itself_o the_o three_o distinction_n of_o sound_n can_v be_v conceive_v clear_o enough_o by_o the_o name_n i_o have_v use_v of_o clear_a and_o hoarse_a nor_o by_o any_o other_o that_o i_o know_v and_o therefore_o it_o be_v needful_a to_o explain_v they_o by_o example_n when_o i_o say_v hoarse_a i_o understand_v whisper_a and_o hiss_v and_o whatsoever_o be_v like_a to_o these_o by_o what_o appellation_n soever_o it_o be_v express_v and_o sound_v of_o this_o kind_n seem_v to_o be_v make_v by_o the_o force_n of_o some_o strong_a wind_n rake_v rather_o then_o strike_v such_o hard_a body_n as_o it_o fall_v upon_o on_o the_o contrary_a when_o i_o use_v the_o word_n clear_a i_o do_v not_o understand_v such_o a_o sound_n as_o may_v be_v easy_o and_o distinct_o hear_v for_o so_o whisper_v will_v be_v clear_a but_o such_o as_o be_v make_v by_o somewhat_o that_o be_v break_v and_o such_o as_o be_v clamour_v tinkle_a the_o sound_n of_o a_o trumpet_n etc._n etc._n and_o to_o express_v it_o significant_o in_o one_o word_n noise_z and_o see_v no_o sound_n be_v make_v but_o by_o the_o concourse_n of_o two_o body_n at_o the_o least_o by_o which_o concourse_n it_o be_v necessary_a that_o there_o be_v as_o well_o reaction_n as_o action_n that_o be_v to_o say_v one_o motion_n opposite_a to_o another_o it_o follow_v that_o according_a as_o the_o proportion_n between_o those_o two_o opposite_a motion_n be_v diversify_v so_o the_o sound_n which_o be_v make_v will_v be_v different_a from_o one_o another_o and_o whensoever_o the_o proportion_n between_o they_o be_v so_o great_a as_o that_o the_o motion_n of_o one_o of_o the_o body_n be_v insensible_a if_o compare_v with_o the_o motion_n of_o the_o other_o than_o the_o sound_n will_v not_o be_v of_o the_o same_o kind_n as_o when_o the_o wind_n fall_v very_o oblique_o upon_o a_o hard_a body_n or_o when_o a_o hard_a body_n be_v carry_v swift_o through_o the_o air_n for_o then_o there_o be_v make_v that_o sound_n which_o i_o call_v a_o hoarse_a sound_n in_o greek_a 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d 〈◊〉_d therefore_o the_o breath_n blow_v with_o violence_n from_o the_o mouth_n make_v a_o hiss_v because_o in_o go_v out_o it_o rake_n the_o superficies_n of_o the_o lip_n who_o reaction_n against_o the_o force_n of_o the_o breath_n be_v not_o sensible_a and_o this_o be_v the_o cause_n why_o the_o wind_n have_v that_o hoarse_a sound_n also_o if_o two_o body_n how_o hard_o soever_o be_v rub_v together_o with_o no_o great_a pressure_n they_o make_v a_o hoarse_a sound_n and_o this_o hoarse_a sound_n when_o it_o be_v make_v as_o i_o have_v say_v by_o the_o air_n rake_v the_o superficies_n of_o a_o hard_a body_n seem_v to_o be_v nothing_o but_o the_o divide_n of_o the_o air_n into_o innumerable_a and_o very_a small_a file_n for_o the_o asperity_n of_o the_o superficies_n do_v by_o the_o eminency_n of_o its_o innumerable_a part_n divide_v or_o cut_v in_o piece_n the_o air_n that_o slide_v upon_o it_o 4_o noise_n or_o that_o which_o i_o call_v clear_a sound_n be_v make_v two_o way_n one_o by_o two_o hoarse_a sound_n make_v by_o opposite_a motion_n the_o other_o by_o collision_n or_o by_o the_o sudden_a pull_v asunder_o of_o two_o body_n whereby_o their_o small_a particle_n be_v put_v into_o commotion_n or_o be_v already_o in_o commotion_n sudden_o restore_v themselves_o again_o which_o motion_n make_v impression_n upon_o the_o medium_fw-la be_v propagate_v to_o the_o organ_n of_o hear_v and_o see_v there_o be_v in_o this_o collision_n or_o divulsion_n a_o endeavour_n in_o the_o particle_n of_o one_o body_n opposite_a to_o the_o endeavour_n of_o the_o particle_n of_o the_o other_o body_n there_o will_v also_o be_v make_v in_o the_o organ_n of_o hear_v a_o like_a opposition_n of_o endeavour_n that_o be_v to_o say_v of_o motion_n and_o consequent_o the_o sound_n arise_v from_o thence_o will_v be_v make_v by_o two_o opposite_a motion_n that_o be_v to_o say_v by_o two_o opposite_a hoarse_a sound_n in_o one_o and_o the_o same_o part_n of_o the_o organ_n for_o as_o i_o have_v already_o say_v a_o hoarse_a sound_n suppose_v the_o sensible_a motion_n of_o but_o one_o of_o the_o body_n and_o this_o opposition_n of_o motion_n in_o the_o organ_n be_v the_o cause_n why_o two_o body_n make_v a_o noise_n when_o they_o be_v either_o sudden_o strike_v against_o one_o another_o or_o sudden_o break_v asunder_o 5_o this_o be_v grant_v and_o see_v withal_o that_o thunder_n be_v make_v by_o the_o vehement_a eruption_n of_o the_o air_n out_o of_o the_o cavity_n of_o congeal_v cloud_n the_o cause_n of_o the_o great_a noise_n or_o clap_n may_v be_v the_o sudden_a break_n asunder_o of_o the_o ice_n for_o in_o this_o action_n it_o be_v necessary_a that_o there_o be_v not_o only_o a_o great_a concussion_n of_o the_o small_a particle_n of_o the_o break_a part_n but_o also_o that_o this_o concussion_n by_o be_v communicate_v to_o the_o air_n be_v carry_v to_o the_o organ_n of_o hear_v &_o make_v impression_n upon_o it_o and_o then_o from_o the_o first_o reaction_n of_o the_o organ_n proceed_v that_o first_o and_o great_a sound_n which_o be_v make_v by_o the_o collision_n of_o the_o part_n whilst_o they_o restore_v themselves_o and_o see_v there_o be_v
in_o all_o concussion_n a_o reciprocation_n of_o motion_n forward_o and_o backward_o in_o the_o part_n strike_v for_o opposite_a motion_n can_v extinguish_v one_o another_o in_o a_o instant_n as_o i_o have_v show_v in_o the_o 11_o art_n of_o the_o 8_o chap._n it_o follow_v necessary_o that_o the_o sound_n will_v both_o continue_v and_o grow_v weak_a and_o weak_a till_o at_o last_o the_o action_n of_o the_o reciprocate_a air_n grow_v so_o weak_a as_o to_o be_v unperceptible_a wherefore_o a_o possible_a cause_n be_v give_v both_o of_o the_o first_o fierce_a noise_n of_o the_o thunder_n and_o also_o of_o the_o murmur_n that_o follow_v it_o the_o cause_n of_o the_o great_a sound_n from_o a_o discharge_v piece_n of_o ordnance_n be_v like_o that_o of_o a_o clap_n of_o thunder_n for_o the_o gunpowder_n be_v fire_v do_v in_o its_o endeavour_n to_o go_v out_o attempt_v every_o way_n the_o side_n of_o the_o metal_n in_o such_o manner_n as_o that_o it_o enlarge_v the_o circumference_n all_o along_o and_o withal_o shorten_v the_o axis_fw-la so_o that_o while_o the_o piece_n of_o ordnance_n be_v in_o discharge_v it_o be_v make_v both_o wide_a and_o short_a than_o it_o be_v before_o and_o therefore_o also_o present_o after_o it_o be_v discharge_v its_o wideness_n will_v be_v diminish_v and_o its_o length_n increase_v again_o by_o the_o restitution_n of_o all_o the_o particle_n of_o the_o matter_n of_o which_o it_o consist_v to_o their_o former_a position_n and_o this_o be_v do_v with_o such_o motion_n of_o the_o part_n as_o be_v not_o only_o very_o vehement_a but_o also_o opposite_a to_o one_o another_o which_o motion_n be_v communicate_v to_o the_o air_n make_v impression_n upon_o the_o organ_n and_o by_o the_o reaction_n of_o the_o organ_n create_v a_o sound_n which_o last_v for_o some_o time_n as_o i_o have_v already_o show_v in_o this_o article_n i_o note_v by_o the_o way_n as_o not_o belong_v to_o this_o place_n that_o the_o possible_a cause_n why_o a_o gun_n recoil_v when_o it_o be_v shoot_v off_o may_v be_v this_o that_o be_v first_o swell_v by_o the_o force_n of_o the_o fire_n and_o afterward_o restore_v itself_o from_o this_o restitution_n there_o proceed_v a_o endeavour_n from_o all_o the_o side_n towards_o the_o cavity_n and_o consequent_o this_o endeavour_n be_v in_o those_o part_n which_o be_v next_o the_o breech_n which_o be_v not_o hollow_a but_o solid_a the_o effect_n of_o the_o restitution_n be_v by_o it_o hinder_v and_o divert_v into_o the_o length_n and_o by_o this_o mean_v both_o the_o breech_n and_o the_o whole_a gun_n be_v thrust_v backward_o and_o the_o more_o forcible_o by_o how_o much_o the_o force_n be_v great_a by_o which_o the_o part_n next_o the_o breech_n be_v restore_v to_o its_o former_a posture_n that_o be_v to_o say_v by_o how_o much_o the_o thin_a be_v that_o part_n the_o cause_n therefore_o why_o gun_n recoil_v some_o more_o some_o less_o be_v the_o difference_n of_o their_o thickness_n towards_o the_o breech_n &_o the_o great_a that_o thickness_n be_v the_o less_o they_o recoil_v and_o contrary_o 6_o also_o the_o cause_n why_o the_o sound_n of_o a_o pipe_n which_o be_v make_v by_o blow_v into_o it_o be_v nevertheless_o clear_a be_v the_o same_o with_o that_o of_o the_o sound_n which_o be_v make_v by_o collision_n for_o if_o the_o breath_n when_o it_o be_v blow_v into_o a_o pipe_n do_v only_o rake_v its_o concave_a superficies_n or_o fall_v upon_o it_o with_o a_o very_a sharp_a angle_n of_o incidence_n the_o sound_n will_v not_o be_v clear_a but_o hoarse_a but_o if_o the_o angle_n be_v great_a enough_o the_o percussion_n which_o be_v make_v against_o one_o of_o the_o hollow_a side_n will_v be_v reverberate_v to_o the_o opposite_a side_n and_o so_o successive_a repercussion_n will_v be_v make_v from_o side_n to_o side_n till_o at_o last_o the_o whole_a concave_a superficies_n of_o the_o pipe_n be_v put_v into_o motion_n which_o motion_n will_v be_v reciprocate_v as_o it_o be_v in_o collision_n and_o this_o reciprocation_n be_v propagate_v to_o the_o organ_n from_o the_o reaction_n of_o the_o organ_n will_v arise_v a_o clear_a sound_n such_o as_o be_v make_v by_o collision_n or_o by_o break_v asunder_o of_o hard_a body_n in_o the_o same_o manner_n it_o be_v with_o the_o sound_n of_o a_o man_n voice_n for_o when_o the_o breath_n pass_v out_o without_o interruption_n and_o do_v but_o light_o touch_v the_o cavity_n through_o which_o it_o be_v send_v the_o sound_v it_o make_v be_v a_o hoarse_a sound_n but_o if_o in_o go_v out_o it_o strike_v strong_o upon_o the_o larinx_n than_o a_o clear_a sound_n be_v make_v as_o in_o a_o pipe_n and_o the_o same_o breath_n as_o it_o come_v in_o divers_a manner_n to_o the_o palate_n the_o tongue_n the_o lip_n the_o tooth_n and_o other_o organ_n of_o speech_n so_o the_o sound_v into_o which_o it_o be_v articulate_v become_v different_a from_o one_o another_o 7_o i_o call_v that_o primary_n sound_v which_o be_v generate_v by_o motion_n from_o the_o sound_a body_n to_o the_o organ_n in_o a_o straight_a line_n without_o reflection_n and_o i_o call_v that_o reflect_v sound_n which_o be_v generate_v by_o one_o or_o more_o reflection_n be_v the_o same_o with_o that_o we_o call_v echo_n and_o be_v iterate_v as_o often_o as_o there_o be_v reflection_n make_v from_o the_o object_n to_o the_o eare._n and_o these_o reflection_n be_v make_v by_o hill_n wall_n and_o other_o resist_a body_n so_o place_v as_o that_o they_o make_v more_o or_o few_o reflection_n of_o the_o motion_n according_a as_o they_o be_v themselves_o more_o or_o few_o in_o number_n and_o they_o make_v they_o more_o or_o less_o frequent_o according_a as_o they_o be_v more_o or_o less_o distant_a from_o one_o another_o now_o the_o cause_n of_o both_o these_o thing_n be_v to_o be_v seek_v for_o in_o the_o situation_n of_o the_o reflect_a body_n as_o be_v usual_o do_v in_o sight_n for_o the_o law_n of_o reflection_n be_v the_o same_o in_o both_o namely_o that_o the_o angle_n of_o incidence_n and_o reflection_n be_v equal_a to_o one_o another_o if_o therefore_o in_o a_o hollow_a elliptique_a body_n who_o inside_n be_v well_o polish_a or_o in_o two_o right_a parabolical_a solid_n which_o be_v join_v together_o by_o one_o common_a base_a there_o be_v place_v a_o sound_a body_n in_o one_o of_o the_o burn_a point_n &_o the_o ear_n in_o the_o other_o there_o will_v be_v hear_v a_o sound_n by_o many_o degree_n great_a than_o in_o the_o open_a air_n and_o both_o this_o and_o the_o burn_a of_o such_o combustible_a thing_n as_o be_v put_v in_o the_o same_o place_n be_v set_v on_o fire_n by_o the_o sunbeam_n be_v effect_n of_o one_o and_o the_o same_o cause_n but_o as_o when_o the_o visible_a object_n be_v place_v in_o one_o of_o the_o burn_a point_n it_o be_v not_o distinct_o see_v in_o the_o other_o because_o every_o part_n of_o the_o object_n be_v see_v in_o every_o line_n which_o be_v reflect_v from_o the_o concave_a superficies_n to_o the_o eye_n make_v a_o confusion_n in_o the_o sight_n so_o neither_o be_v sound_v hear_v articulate_o and_o distinct_o when_o it_o come_v to_o the_o ear_n in_o all_o those_o reflect_a line_n and_o this_o may_v be_v the_o reason_n why_o in_o church_n which_o have_v arch_v rooff_n though_o they_o be_v neither_o elliptical_a nor_o parabolical_a yet_o because_o their_o figure_n be_v not_o much_o different_a from_o these_o the_o voice_n from_o the_o pulpit_n will_v not_o be_v hear_v so_o articulate_o as_o it_o will_v be_v if_o there_o be_v no_o vault_v at_o all_o 8_o concern_v the_o uniformity_n and_o duration_n of_o sound_n both_o which_o have_v one_o common_a cause_n we_o may_v observe_v that_o such_o body_n as_o be_v strike_v yield_v a_o unequal_a or_o harsh_a sound_n be_v very_o heterogeous_a that_o be_v to_o say_v they_o consist_v of_o part_n which_o be_v very_o unlike_a both_o in_o figure_n and_o hardness_n such_o as_o be_v wood_n stones_n and_o other_o not_o a_o few_o when_o these_o be_v strike_v there_o follow_v a_o concussion_n of_o their_o internal_a particle_n and_o a_o restitution_n of_o they_o again_o but_o they_o be_v neither_o move_v alike_o nor_o have_v they_o the_o same_o action_n upon_o one_o another_o some_o of_o they_o recoil_v from_o the_o stroke_n while_o other_o which_o have_v already_o finish_v their_o recoyling_n be_v now_o return_v by_o which_o mean_n they_o hinder_v and_o stop_v on_o another_o and_o from_o hence_o it_o be_v that_o their_o motion_n be_v not_o only_o unequal_a and_o harsh_a but_o also_o that_o their_o reciprocation_n come_v to_o be_v quick_o extinguish_v whensoever_o therefore_o this_o motion_n be_v propagate_v to_o the_o ear_n the_o sound_v it_o make_v be_v unequal_a and_o of_o small_a duration_n on_o the_o contrary_a if_o a_o body_n
it_o alone_o and_o pass_v on_o to_o the_o search_n of_o the_o cause_n of_o gravity_n 2_o now_o we_o call_v those_o body_n heavy_a which_o unless_o they_o be_v hinder_v by_o some_o force_n be_v carry_v towards_o the_o centre_n of_o the_o earth_n and_o that_o by_o their_o own_o accord_n for_o aught_o we_o can_v by_o sense_n perceive_v to_o the_o contrary_n some_o philosopher_n therefore_o have_v be_v of_o opinion_n that_o the_o descent_n of_o heavy_a body_n proceed_v from_o some_o internal_a appetite_n by_o which_o when_o they_o be_v cast_v upward_o they_o descend_v again_o as_o move_v by_o themselves_o to_o such_o place_n as_o be_v agreeable_a to_o their_o nature_n other_o think_v they_o be_v attract_v by_o the_o earth_n to_o the_o former_a i_o can_v assent_v because_o i_o think_v i_o have_v already_o clear_o enough_o demonstrate_v that_o there_o can_v be_v no_o beginning_n of_o motion_n but_o from_o a_o external_a &_o move_a body_n and_o consequent_o that_o whatsoever_o have_v motion_n or_o endeavour_n towards_o any_o place_n will_v always_o move_v or_o endeavour_v towards_o that_o same_o place_n unless_o it_o be_v hinder_v by_o the_o reaction_n of_o some_o external_a body_n heavy_a body_n therefore_o be_v once_o cast_v upward_o can_v be_v cast_v down_o again_o but_o by_o external_a motion_n beside_o see_v inanimate_a body_n have_v no_o appetite_n at_o all_o it_o be_v ridiculous_a to_o think_v that_o by_o their_o own_o innate_a appetite_n they_o shall_v to_o preserve_v themselves_o not_o understand_v what_o preserve_v they_o forsake_v the_o place_n they_o be_v in_o and_o transfer_v themselves_o to_o another_o place_n whereas_o man_n who_o have_v both_o appetite_n and_o understanding_n can_v for_o the_o preservation_n of_o his_o own_o life_n raise_v himself_o by_o leap_v above_o three_o or_o four_o foot_n from_o the_o ground_n last_o to_o attribute_v to_o create_a body_n the_o power_n to_o move_v themselves_o what_o be_v it_o else_o then_o to_o say_v that_o there_o be_v creature_n which_o have_v no_o dependence_n upon_o the_o creator_n to_o the_o late_a who_o attribute_v the_o descent_n of_o heavy_a body_n to_o the_o attraction_n of_o the_o earth_n i_o assent_n but_o by_o what_o motion_n this_o be_v do_v have_v not_o as_o yet_o be_v explain_v by_o any_o man_n i_o shall_v therefore_o in_o this_o place_n say_v somewhat_o of_o the_o manner_n and_o of_o the_o way_n by_o which_o the_o earth_n by_o its_o action_n attract_v heavy_a body_n 3_o that_o by_o the_o supposition_n of_o simple_a motion_n in_o the_o sun_n homogeneous_a body_n be_v congregat_v and_o heterogeneous_a dissipate_v have_v already_o be_v demonstrate_v in_o the_o 5_o article_n of_o the_o 21_o chapter_n i_o have_v also_o suppose_v that_o there_o be_v intermingle_v with_o the_o pure_a air_n certain_a little_a body_n or_o as_o other_o call_v they_o atom_n which_o by_o reason_n of_o their_o extreme_a smallness_n be_v invisible_a and_o differ_v from_o one_o another_o in_o consistence_n figure_n motion_n &_o magnitude_n from_o whence_o it_o come_v to_o pass_v that_o some_o of_o they_o be_v congregat_v to_o the_o earth_n other_o to_o other_o planet_n and_o other_o be_v carry_v up_o and_o down_o in_o the_o space_n between_o and_o see_v those_o which_o be_v carry_v to_o the_o earth_n differ_v from_o one_o another_o in_o figure_n motion_n and_o magnitude_n they_o will_v fall_v upon_o the_o earth_n some_o with_o great_a other_o with_o less_o impetus_fw-la and_o see_v also_o that_o we_o compute_v the_o several_a degree_n of_o gravity_n no_o otherwise_o then_o by_o this_o their_o fall_n upon_o the_o earth_n with_o great_a or_o less_o impetus_fw-la it_o follow_v that_o we_o conclude_v those_o to_o be_v the_o more_o heavy_a that_o have_v the_o great_a impetus_fw-la and_o those_o to_o be_v less_o heavy_a that_o have_v the_o less_o impetus_fw-la our_o enquiry_n therefore_o must_v be_v by_o what_o mean_v it_o may_v come_v to_o pass_v that_o of_o body_n which_o descend_v from_o above_o to_o the_o earth_n some_o be_v carry_v with_o great_a other_o with_o less_o impetus_fw-la that_o be_v to_o say_v some_o be_v more_o heavy_a than_o other_o we_o must_v also_o inquire_v by_o what_o mean_v such_o body_n as_o settle_v upon_o the_o earth_n may_v by_o the_o earth_n itself_o be_v force_v to_o ascend_v 4_o let_v the_o circle_n make_v upon_o the_o centre_n c_o in_o the_o 2d_o figure_n be_v a_o great_a circle_n in_o the_o superficies_n of_o the_o earth_n pass_v through_o the_o point_n a_o and_o b._n also_o let_v any_o heavy_a body_n as_o the_o stone_n a_o d_o be_v place_v any_o where_o in_o the_o plain_a of_o the_o aequator_fw-la and_o let_v it_o be_v conceive_v to_o be_v cast_v up_o from_o a_o d_o perpendicular_o or_o to_o be_v carry_v in_o any_o other_o line_n to_o e_o and_o suppose_v to_o rest_v there_o therefore_o how_o much_o space_n soever_o the_o stone_n take_v up_o in_o a_o d_o so_o much_o space_n it_o take_v up_o now_o in_o e._n and_o because_o all_o place_n be_v suppose_v to_o be_v full_a the_o space_n a_o d_o will_v be_v fill_v by_o the_o air_n which_o flow_v into_o it_o first_o from_o the_o near_a place_n of_o the_o earth_n and_o afterward_o successive_o from_o more_o remote_a place_n upon_o the_o centre_n c_o let_v a_o circle_n be_v understand_v to_o be_v draw_v through_o e_z and_o let_v the_o plain_a space_n which_o be_v between_o the_o superficies_n of_o the_o earth_n and_o that_o circle_n be_v divide_v into_o plain_a orb_n equal_a and_o concentrique_fw-la of_o which_o let_v that_o be_v the_o first_o which_o be_v contain_v by_o the_o two_o perimeter_n that_o pass_v through_o a_o &_o d._n whilst_o therefore_o the_o air_n which_o be_v in_o the_o first_o orb_n fill_v the_o place_n a_o d_o the_o orb_n itself_o be_v make_v so_o much_o less_o and_o consequent_o its_o latitude_n be_v less_o than_o the_o straight_a line_n a_o d._n wherefore_o there_o will_v necessary_o descend_v so_o much_o air_n from_o the_o orb_n next_o abvoe_n in_o like_a manner_n for_o the_o same_o cause_n there_o will_v also_o be_v a_o descent_n of_o air_n from_o the_o orb_n next_o above_o that_o and_o so_o by_o succession_n from_o the_o orb_n in_o which_o the_o stone_n be_v at_o rest_n in_o e._n either_o therefore_o the_o stone_n itself_o or_o so_o much_o air_n will_v descend_v and_o see_v air_n be_v by_o the_o diurnal_a revolution_n of_o the_o earth_n more_o easy_o thrust_v away_o than_o the_o stone_n the_o air_n which_o be_v in_o the_o orb_n that_o contain_v the_o stone_n will_v be_v force_v further_a upward_o than_o the_o stone_n but_o this_o without_o the_o admission_n of_o vacuum_n can_v be_v unless_o so_o much_o air_n descend_v to_o e_z from_o the_o place_n next_o above_o which_o be_v do_v the_o stone_n will_v be_v thrust_v downward_o by_o this_o mean_n therefore_o the_o stone_n now_o receive_v the_o beginning_n of_o its_o descent_n that_o be_v to_o say_v of_o its_o gravity_n furthermore_o whatsoever_o be_v once_o move_v will_v be_v move_v continual_o as_o have_v be_v show_v in_o the_o 19_o article_n of_o the_o 8_o chapter_n in_o the_o same_o way_n and_o with_o the_o same_o celerity_n except_o it_o be_v retard_v or_o accelerate_a by_o some_o external_a movent_fw-la now_o the_o air_n which_o be_v the_o only_a body_n that_o be_v interpose_v between_o the_o earth_n a_o and_o the_o stone_n above_o it_o e_z will_v have_v the_o same_o action_n in_o every_o point_n of_o the_o straight_a line_n e_o a_o which_o it_o have_v in_o e._n but_o it_o depress_v the_o stone_n in_o e_z and_o therefore_o also_o it_o will_v depress_v it_o equal_o in_o every_o point_n of_o the_o straight_a line_n e_o a._n wherefore_o the_o stone_n will_v descend_v from_o e_o to_o a_o with_o accelerate_a motion_n the_o possible_a cause_n therefore_o of_o the_o descent_n of_o heavy_a body_n under_o the_o aequator_fw-la be_v the_o diurnal_a motion_n of_o the_o earth_n and_o the_o same_o demonstration_n will_v serve_v if_o the_o stone_n be_v place_v in_o the_o plain_a of_o any_o other_o circle_n parallel_n to_o the_o aequator_fw-la but_o because_o this_o motion_n have_v by_o reason_n of_o its_o great_a slowness_n less_o force_n to_o thrust_v off_o the_o air_n in_o the_o parallel_a circle_n then_o in_o the_o aequator_fw-la and_o no_o force_n at_o all_o at_o the_o pole_n it_o may_v well_o be_v think_v for_o it_o be_v a_o certain_a consequent_a that_o heavy_a body_n descend_v with_o less_o and_o less_o velocity_n as_o they_o be_v more_o &_o more_o remote_a from_o the_o aequator_fw-la &_o that_o at_o the_o pole_n themselves_o they_o will_v either_o not_o descend_v at_o all_o or_o not_o descend_v by_o the_o axis_n which_o whether_o it_o be_v true_a or_o false_a experience_n must_v determine_v but_o it_o be_v hard_o to_o make_v the_o experiment_n both_o because_o the_o
time_n of_o their_o descent_n can_v be_v easy_o measure_v with_o sufficient_a exactness_n and_o also_o because_o the_o place_n near_o the_o pole_n be_v inaccessible_a nevertheless_o this_o we_o know_v that_o by_o how_o much_o the_o near_o we_o come_v to_o the_o pole_n by_o so_o much_o the_o great_a be_v the_o flake_n of_o the_o snow_n that_o fall_v and_o by_o how_o much_o the_o more_o swift_o such_o body_n descend_v as_o be_v fluid_a and_o dissipable_a by_o so_o much_o the_o small_a be_v the_o particle_n into_o which_o they_o be_v dissipate_v 5_o suppose_v therefore_o this_o to_o be_v the_o cause_n of_o the_o descent_n of_o heavy_a body_n it_o will_v follow_v that_o their_o motion_n will_v be_v accelerate_a in_o such_o manner_n as_o that_o the_o space_n which_o be_v transmit_v by_o they_o in_o the_o several_a time_n will_v have_v to_o one_o another_o the_o same_o proportion_n which_o the_o odd_a number_n have_v in_o succession_n from_o unity_n for_o if_o the_o straight_a line_n ea_fw-la be_v divide_v into_o any_o number_n of_o equal_a part_n the_o heavy_a body_n descend_v will_v by_o reason_n of_o the_o perpetual_a action_n of_o the_o diurnal_a motion_n receive_v from_o the_o air_n in_o every_o one_o of_o those_o time_n in_o every_o several_a point_n of_o the_o straight_a line_n ea_fw-la a_o several_a new_a and_o equal_a impulsion_n and_o therefore_o also_o in_o every_o one_o of_o those_o time_n it_o will_v acquire_v a_o several_a and_o equal_a degree_n of_o celerity_n and_o from_o hence_o it_o follow_v by_o that_o which_o galilaeus_fw-la have_v in_o his_o dialogue_n of_o motion_n demonstrate_v that_o heavy_a body_n descend_v in_o the_o several_a time_n with_o such_o difference_n of_o transmit_v space_n as_o be_v equal_a to_o the_o difference_n of_o the_o square_a number_n that_o succeed_v one_o another_o from_o unity_n which_o square_a number_n be_v 1_o 4_o 9_o 16_o etc._n etc._n their_o difference_n be_v 3_o 5_o 7_o that_o be_v to_o say_v the_o odd_a number_n which_o succeed_v another_o from_o unity_n against_o this_o cause_n of_o gravity_n which_o i_o have_v give_v it_o will_v perhaps_o be_v object_v that_o if_o a_o heavy_a body_n be_v place_v in_o the_o bottom_n of_o some_o hollow_a cylinder_n of_o iron_n or_o adamant_n and_o the_o bottom_n be_v turn_v upward_o the_o body_n will_v descend_v though_o the_o air_n above_o can_v depress_v it_o much_o less_o accelerate_v its_o motion_n but_o it_o be_v to_o be_v consider_v that_o there_o can_v be_v no_o cylinder_n or_o cavern_n but_o such_o as_o be_v support_v by_o the_o earth_n and_o be_v so_o support_v be_v together_o with_o the_o earth_n carry_v about_o by_o its_o diurnal_a motion_n for_o by_o this_o mean_v the_o bottom_n of_o the_o cylinder_n will_v be_v as_o the_o superficies_n of_o the_o earth_n and_o by_o thrust_v off_o the_o next_o and_o low_a air_n will_v make_v the_o uppermost_a air_n depress_v the_o heavy_a body_n which_o be_v at_o the_o top_n of_o the_o cylinder_n in_o such_o manner_n as_o be_v above_o explicate_v 6_o the_o gravity_n of_o water_n be_v so_o great_a as_o by_o experience_n we_o find_v it_o be_v the_o reason_n be_v demand_v by_o many_o why_o those_o that_o dive_v how_o deep_a soever_o they_o go_v under_o water_n do_v not_o at_o all_o feel_v the_o weight_n of_o the_o water_n which_o lie_v upon_o they_o and_o the_o cause_n seem_v to_o be_v this_o that_o all_o body_n by_o how_o much_o the_o heavy_a they_o be_v by_o so_o much_o the_o great_a be_v the_o endeavour_n by_o which_o they_o tend_v downward_o but_o the_o body_n of_o a_o man_n be_v heavy_a than_o so_o much_o water_n as_o be_v equal_a to_o it_o in_o magnitude_n and_o therefore_o the_o endeavour_n downward_o of_o a_o man_n body_n be_v great_a than_o that_o of_o water_n and_o see_v all_o endeavour_n be_v motion_n the_o body_n also_o of_o a_o man_n will_v be_v carry_v towards_o the_o bottom_n with_o great_a velocity_n than_o so_o much_o water_n wherefore_o there_o be_v great_a reaction_n from_o the_o bottom_n and_o the_o endeavour_v upward_o be_v equal_a to_o the_o endeavour_n downward_o whether_o the_o water_n be_v press_v by_o water_n or_o by_o another_o body_n which_o be_v heavy_a than_o water_n and_o therefore_o by_o these_o two_o opposite_a equal_a endeavour_n the_o endeavour_n both_o way_n in_o the_o water_n be_v take_v away_o and_o consequent_o those_o that_o dive_v be_v not_o at_o all_o press_v by_o it_o coral_n from_o hence_o also_o it_o be_v manifest_a that_o water_n in_o water_n have_v no_o weight_n at_o all_o because_o all_o the_o part_n of_o water_n both_o the_o part_n above_o and_o the_o part_n that_o be_v direct_o under_o tend_v towards_o the_o bottom_n with_o equal_a endeavour_n and_o in_o the_o same_o straight_a line_n 7_o if_o a_o body_n float_v upon_o the_o water_n the_o weight_n of_o that_o body_n be_v equal_a to_o the_o weight_n of_o so_o much_o water_n as_o will_v fill_v the_o place_n which_o the_o immersed_a part_n of_o the_o body_n take_v up_o within_o the_o water_n let_v of_o in_o the_o 3d_o figure_n be_v a_o body_n float_v in_o the_o water_n abcd_v and_o let_v the_o part_n e_o be_v above_o and_o the_o other_o part_n f_o under_o the_o water_n i_o say_v the_o weight_n of_o the_o whole_a body_n of_o be_v equal_a to_o the_o weight_n of_o so_o much_o water_n as_o the_o space_n f_o will_v receive_v for_o see_v the_o weight_n of_o the_o body_n of_o force_v the_o water_n out_o of_o the_o space_n f_o and_o place_v it_o upon_o the_o superficies_n ab_fw-la where_o it_o press_v downward_o it_o follow_v that_o from_o the_o resistance_n of_o the_o bottom_n there_o will_v also_o be_v a_o endeavour_n upward_o and_o see_v again_o that_o by_o this_o endeavour_n of_o the_o water_n upward_o the_o body_n of_o be_v lift_v up_o it_o follow_v that_o if_o the_o endeavour_n of_o the_o body_n downward_o be_v not_o equal_a to_o the_o endeavour_n of_o the_o water_n upward_o either_o the_o whole_a body_n of_o will_n by_o reason_n of_o that_o inequality_n of_o their_o endeavour_n or_o moment_n be_v raise_v out_o of_o the_o water_n or_o else_o it_o will_v descend_v to_o the_o bottom_n but_o it_o be_v suppose_v to_o stand_v so_o as_o neither_o to_o ascend_v nor_o descend_v wherefore_o there_o be_v a_o aequilibrium_fw-la between_o the_o two_o endeavour_n that_o be_v to_o say_v the_o weight_n of_o the_o body_n of_o be_v equal_a to_o the_o weight_n of_o so_o much_o water_n as_o the_o space_n f_o will_v receive_v which_o be_v to_o be_v prove_v 8_o from_o hence_o it_o follow_v that_o any_o body_n of_o how_o great_a magnitude_n soever_o provide_v it_o consist_v of_o matter_n less_o heavy_a than_o water_n may_v nevertheless_o float_v upon_o any_o quantity_n of_o water_n how_o little_a soever_o let_v abcd_n in_o the_o four_o figure_n be_v a_o vessel_n and_o in_o it_o let_v efgh_o be_v a_o body_n consist_v of_o matter_n which_o be_v less_o heavy_a than_o water_n and_o let_v the_o space_n agcf_n be_v fill_v with_o water_n i_o say_v the_o body_n efgh_o will_v not_o sink_v to_o the_o bottom_n dc_o for_o see_v the_o matter_n of_o the_o body_n efgh_n be_v less_o heavy_a than_o water_n if_o the_o whole_a space_n without_o abcd_n be_v full_a of_o water_n yet_o some_o part_n of_o the_o body_n efgh_o as_o efik_n will_v be_v above_o the_o water_n and_o the_o weight_n of_o so_o much_o water_n as_o will_v fill_v the_o space_n ighk_n will_v be_v equal_a to_o the_o weight_n of_o the_o whole_a body_n efgh_o and_o consequent_o gh_a will_v not_o touch_v the_o bottom_n dc_o as_o for_o the_o side_n of_o the_o vessel_n it_o be_v no_o matter_n whether_o they_o be_v hard_a or_o fluid_a for_o they_o serve_v only_o to_o terminate_v the_o water_n which_o may_v be_v do_v as_o well_o by_o water_n as_o by_o any_o other_o matter_n how_o hard_o soever_o and_o the_o water_n without_o the_o vessel_n be_v terminate_v somewhere_o so_o as_o that_o it_o can_v spread_v no_o further_o the_o part_n therefore_o efig_n will_v be_v extant_a above_o the_o water_n agcf_n which_o be_v contain_v in_o the_o vessel_n wherefore_o the_o body_n efgh_o will_v also_o float_v upon_o the_o water_n agcf_n how_o little_a soever_o that_o water_n be_v which_o be_v to_o be_v demonstrate_v 9_o in_o the_o four_o article_n of_o the_o 26_o chapter_n there_o be_v bring_v for_o the_o prove_v of_o vacuum_n the_o experiment_n of_o water_n enclose_v in_o a_o vessel_n which_o water_n the_o orifice_n above_o be_v open_v be_v eject_v upward_o by_o the_o impulsion_n of_o the_o air_n it_o be_v therefore_o demand_v see_v water_n be_v heavy_a than_o air_n how_o that_o can_v be_v do_v let_v the_o second_o figure_n of_o the_o same_o 26_o chap._n be_v consider_v where_o the_o water_n be_v with_o great_a force_n inject_v by_o
iron_n by_o its_o action_n upon_o the_o loadstone_n do_v imprint_v in_o it_o a_o endeavour_n towards_o the_o other_o pole_n namely_o towards_o the_o south_n pole_n it_o happen_v therefore_o in_o these_o reciprocation_n or_o motion_n forward_o and_o backward_o of_o the_o particle_n of_o the_o stone_n and_o of_o the_o iron_n betwixt_o the_o north_n &_o the_o south_n that_o while_o in_o one_o of_o they_o the_o motion_n be_v from_o north_n to_o south_n and_o the_o return_n from_o south_n to_o north_n in_o the_o other_o the_o motion_n will_v be_v from_o south_n to_o north_n &_o the_o return_n from_o north_n to_o south_n which_o motion_n be_v opposite_a to_o one_o another_o and_o communicate_v to_o the_o air_n the_o north_n pole_n of_o the_o iron_n while_o the_o attraction_n be_v work_v will_v be_v depress_v towards_o the_o south_n pole_n of_o the_o loadstone_n or_o contrary_o the_o north_n pole_n of_o the_o loadstone_n will_v be_v depress_v towards_o the_o south_n pole_n of_o the_o iron_n and_o the_o axe_n both_o of_o the_o loadstone_n and_o of_o the_o iron_n will_v be_v situate_a in_o the_o same_o straight_a line_n the_o truth_n whereof_o be_v teach_v we_o by_o experience_n as_o for_o the_o propagation_n of_o this_o magnetical_a virtue_n not_o only_o through_o the_o air_n but_o through_o any_o other_o body_n how_o hard_o so_o ever_o it_o be_v not_o to_o be_v wonder_v at_o see_v no_o motion_n can_v be_v so_o weak_a but_o that_o it_o may_v be_v propagate_v infinite_o through_o a_o space_n fill_v with_o body_n of_o any_o hardness_n whatsoever_o for_o in_o a_o full_a medium_fw-la there_o can_v be_v no_o motion_n which_o do_v not_o make_v the_o next_o part_n yield_v and_o that_o the_o next_o and_o so_o successive_o without_o end_n so_o that_o there_o be_v no_o effect_n whatsoever_o but_o to_o the_o production_n thereof_o something_o be_v necessary_o contribute_v by_o the_o several_a motion_n of_o all_o the_o several_a thing_n that_o be_v in_o the_o world_n and_o thus_o much_o concern_v the_o nature_n of_o body_n in_o general_a with_o which_o i_o conclude_v this_o my_o first_o section_n of_o the_o element_n of_o philosophy_n in_o the_o first_o second_o and_o three_o part_n where_o the_o principle_n of_o ratiocination_n consist_v in_o our_o own_o understanding_n that_o be_v to_o say_v in_o the_o legitimate_a use_n of_o such_o word_n as_o we_o ourselves_o constitute_v all_o the_o theorem_n if_o i_o be_v not_o deceive_v be_v right_o demonstrate_v the_o four_o part_n depend_v upon_o hypothesis_n which_o unless_o we_o know_v they_o to_o be_v true_a it_o be_v impossible_a for_o we_o to_o demonstrate_v that_o those_o cause_n which_o i_o have_v there_o explicate_v be_v the_o true_a cause_n of_o the_o thing_n who_o production_n i_o have_v derive_v from_o they_o nevertheless_o see_v i_o have_v assume_v no_o hypothesis_n which_o be_v not_o both_o possible_a and_o easy_a to_o be_v comprehend_v and_o see_v also_o that_o i_o have_v reason_v aright_o from_o those_o assumption_n i_o have_v withal_o sufficient_o demonstrate_v that_o they_o may_v be_v the_o true_a cause_n w_z ch_z be_v the_o end_n of_o physical_a contemplation_n if_o any_o other_o man_n from_o other_o hypothesis_n shall_v demonstrate_v the_o same_o or_o great_a thing_n there_o will_v be_v great_a praise_n and_o thanks_o due_a to_o he_o then_o i_o demand_v for_o myself_o provide_v his_o hypothesis_n be_v such_o as_o be_v conceivable_a for_o as_o for_o those_o that_o say_v any_o thing_n may_v be_v move_v or_o produce_v by_o itself_o by_o species_n by_o its_o own_o power_n by_o substantial_a form_n by_o incorporeal_a substance_n by_o instinct_n by_o anteperistasis_fw-la by_o antipathy_n sympathy_n occult_a quality_n and_o other_o empty_a word_n of_o schoolman_n their_o say_n so_o be_v to_o no_o purpose_n and_o now_o i_o proceed_v to_o the_o phaenomena_n of_o man_n body_n where_o i_o shall_v speak_v of_o the_o optic_n and_o of_o the_o disposition_n affection_n and_o manner_n of_o man_n if_o it_o shall_v please_v god_n to_o give_v i_o life_n and_o show_v their_o cause_n ad_fw-la cap._n fourteen_o fig._n 1._o fig._n 2._o fig._n 3._o fig._n 4._o fig._n 5._o fig_n 6._o fig_n 7._o fig_n 8._o fig_n 9_o fig_n 10._o ad_fw-la cap._n xvi_o fig_n 1_o fig_n 2_o fig_n 3_o fig_n 4_o fig_n 5_o fig_n 6_o fig_n 7_o fig_n 8_o fig_n 9_o fig_n 10_o fig_n 11_o ad_fw-la cap._n xvii_o fig._n 1._o fig._n 2._o fig._n 3._o fig._n 4._o fig._n 5._o fig._n 6._o fig._n 7._o fig._n 8._o cap_n xviii_o fig._n 1._o fig._n 2._o ad_fw-la cap._n xix_o fig_n 1_o fig_n 2_o fig_n 3_o fig_n 4_o fig_n 5_o fig_n 6_o fig_n 7_o fig_n 8_o fig_n 9_o fig_n 10_o cap_n xx._n fig_n 1_o fig_n 2_o fig_n 3_o fig_n 4_o fig_n 5_o ad_fw-la cap_n xxi_o fig_n 1_o fig_n 2_o fig_n 3_o fig_n 4_o fig_n 5_o ad_fw-la cap_n xxii_o fig_n 1_o fig_n 2_o fig_n 3_o ad_fw-la cap_n xxiii_o fig_n 1_o fig_n 2_o fig_n 3_o fig_n 4_o fig_n 5_o fig_n 6_o fig_n 7_o fig_n 8_o fig_n 9_o ad_fw-la cap._n xxiiii_o fig_n 1_o fig_n 2_o fig_n 3_o fig_n 4_o fig_n 5_o fig_n 6_o ad_fw-la cap_n xxvi_o fig_n 1_o fig_n 2_o fig_n 3_o fig_n 4._o fig_n 5._o ad_fw-la cap_n xxvii_o fig_n 1._o fig_n 2_o ad_fw-la cap_n xxviii_o et_fw-la xxx_o fig_n 1._o fig_n 2._o fig_n 3_o fig_n 4_o fig_n 5._o fig_n 6._o