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the_o semicircular_a arm_n c_o d_o upon_o the_o end_n of_o the_o first_o axis_n that_o be_v that_o the_o say_v arm_n may_v by_o their_o revolution_n make_v the_o line_n of_o the_o cross_n describe_v such_o a_o cone_fw-mi about_o the_o first_o axis_n as_o the_o motion_n of_o the_o sun_n do_v about_o the_o axis_fw-la of_o the_o earth_n make_v the_o centre_n of_o the_o earth_n the_o apex_n of_o that_o cone_n which_o will_v be_v do_v if_o the_o say_v semicircular_a arm_n be_v move_v and_o set_v to_o the_o declination_n of_o the_o sun_n for_o that_o day_n or_o that_o a_o additional_a motion_n be_v add_v to_o the_o first_o axis_n that_o the_o clock_n itself_o may_v perform_v it_o this_o may_v be_v do_v twenty_o way_n easy_o enough_o which_o i_o suppose_v will_v be_v sufficient_o
to_o return_v or_o bend_v upward_o again_o so_o that_o the_o plain_a of_o the_o upper_a superficies_n of_o the_o oil_n may_v cut_v that_o end_n of_o the_o siphon_n where_o the_o flame_n be_v between_o the_o top_n of_o the_o mouth_n of_o it_o next_o the_o socket_n and_o the_o return_n thereof_o upward_o then_o by_o a_o counterpoise_n so_o suspend_v this_o siphon_n that_o it_o may_v follow_v the_o oil_n as_o it_o waste_v and_o fit_a into_o the_o return_n of_o the_o siphon_n a_o socket_n and_o wick_n for_o the_o flame_n to_o be_v continue_v a_o contrivance_n somewhat_o of_o this_o kind_n you_o have_v in_o divers_a author_n and_o therefore_o i_o shall_v spend_v less_o time_n in_o the_o description_n thereof_o let_v a_o a_o a_o a_o in_o the_o six_o figure_n then_o represent_v a_o large_a cylindrical_a viol_n of_o glass_n through_o the_o mouth_n b_o of_o which_o the_o cavity_n thereof_o may_v be_v fill_v with_o oil_n and_o also_o the_o end_n d_o and_z float_n c_o of_o a_o convenient_a siphon_n may_v be_v put_v in_o this_o siphon_n d_o d_o d_o p_o g_o must_v be_v make_v long_o enough_o that_o the_o float_n c_o may_v reach_v the_o bottom_n of_o the_o vessel_n when_o the_o oil_n be_v spend_v and_o the_o other_o end_n thereof_o must_v be_v so_o curve_v that_o the_o knee_n of_o the_o siphon_n p_o may_v be_v below_o the_o superficies_n of_o the_o oil_n e_o f_o and_o yet_o that_o the_o socket_n h_n make_v for_o hold_v the_o wick_n for_o the_o flame_n i_o may_v be_v somewhat_o above_o it_o this_o siphon_n d_o d_o d_o p_o g_o with_o its_o socket_n and_o float_n shall_v be_v so_o counterpoise_v with_o a_o weight_n m_o hung_v over_o a_o pulley_n k_o by_o a_o string_n l_o that_o the_o float_n may_v not_o sink_v deep_a into_o the_o surface_n of_o the_o liquor_n but_o swim_v as_o it_o be_v at_o the_o top_n this_o do_v if_o the_o wick_n i_o be_v light_v the_o surface_n of_o the_o oil_n will_v be_v keep_v always_o at_o the_o same_o distance_n below_o the_o flame_n that_o it_o be_v first_o put_v at_o in_o the_o first_o three_o four_o and_o five_o way_n the_o flame_n of_o the_o lamp_n descend_v equal_a space_n with_o the_o superficies_n of_o the_o oil_n in_o the_o vessel_n and_o therefore_o though_o for_o some_o use_v it_o be_v very_o convenient_a as_o in_o annealing_n where_o thing_n be_v to_o be_v cool_v by_o degree_n yet_o for_o many_o other_o it_o be_v not_o especial_o in_o lamp_n furnace_n where_o the_o same_o heat_n be_v to_o be_v continue_v and_o in_o some_o case_n gradual_o increase_v for_o such_o case_n therefore_o the_o first_o and_o second_o way_n will_v be_v very_o convenient_a in_o some_o other_o case_n the_o six_o and_o seven_o way_n which_o do_v much_o the_o same_o thing_n the_o six_o way_n than_o be_v this_o through_o a_o arm_n or_o siphon_n like_o the_o branch_n of_o a_o lamp_n hang_v against_o a_o wall_n fix_v in_o any_o convenient_a place_n the_o oil_n from_o the_o receptacle_n be_v continual_o and_o equal_o supply_v to_o the_o flame_n of_o the_o lamp_n by_o the_o raise_n of_o the_o receptacle_n as_o fast_o as_o the_o oil_n waste_v so_o as_o to_o keep_v the_o superficies_n of_o the_o oil_n always_o in_o the_o same_o horizontal_n plain_n the_o receptacle_n be_v raise_v by_o a_o counterpoise_n hang_v upon_o a_o fusey_n which_o fusey_n be_v a_o part_n of_o a_o archimedean_a spiral_n let_v c_o c_o then_o in_o the_o seven_o figure_n represent_v the_o receptacle_n for_o the_o oil_n be_v a_o cylindrical_a or_o prismatical_a vessel_n of_o what_o bigness_n or_o length_n you_o please_v to_o this_o by_o two_o ear_n at_o l_o l_o fasten_v two_o line_n or_o rope_n k_o k_o the_o end_n of_o both_o which_o be_v fasten_v to_o the_o wheel_n or_o pulley_n g_z though_o one_o of_o they_o do_v run_v over_o the_o pulley_n f._n fit_a into_o this_o receptacle_n be_v make_v a_o cylindrical_a or_o prismatical_a plug_n a_o a_o which_o be_v fix_v in_o some_o convenient_a place_n so_o as_o not_o to_o rise_v or_o sink_v and_o through_o the_o middle_n thereof_o pass_v a_o siphon_n b_o b_o b_o the_o one_o end_n whereof_o extend_v like_o the_o branch_n of_o a_o candle_n or_o lamp_n sustain_v the_o socket_n d_o for_o the_o flame_n e_o which_o be_v feed_v with_o oil_n through_o the_o siphon_n b_o b_o b_o by_o the_o rise_a receptacle_n c_o c._n to_o the_o side_n of_o the_o pulley_n g_o be_v fasten_v a_o fusey_n h_n make_v with_o very_o great_a care_n of_o one_o revolution_n of_o a_o archimedean_a spiral_n not_o begin_v from_o the_o centre_n but_o from_o some_o convenient_a distance_n from_o it_o where_o the_o weight_n i_o hang_v may_v just_o counterpoise_v the_o receptacle_n c_o c_o when_o quite_o empty_a of_o oil_n the_o other_o hang_v counterpoise_n tangent_fw-la to_o the_o large_a part_n of_o this_o spiral_n must_v be_v so_o far_o distant_a from_o the_o centre_n of_o the_o wheel_n g_o that_o the_o same_o weight_n i_o may_v just_o counterpoise_v the_o say_a receptacle_n fill_v topful_a of_o oil_n and_o the_o fusey_n must_v be_v file_v true_a to_o a_o spiral_n draw_v with_o great_a care_n of_o one_o revolution_n between_o those_o two_o point_n i_o say_v here_o of_o one_o revolution_n because_o i_o have_v suppose_v the_o wheel_n or_o pulley_n g_o big_o enough_o by_o one_o revolution_n of_o it_o to_o draw_v up_o the_o receptacle_n the_o whole_a space_n it_o be_v to_o be_v raise_v for_o if_o the_o say_v pulley_n be_v so_o small_a as_o to_o require_v two_o three_o four_o or_o more_o revolution_n then_o must_v the_o piece_n of_o the_o spiral_n between_o those_o point_n be_v draw_v of_o two_o three_o four_o or_o more_o revolution_n proportionable_o which_o be_v very_o artificial_o and_o mechanical_o perform_v the_o receptacle_n c_o c_o will_n be_v raise_v by_o the_o same_o degree_n by_o which_o the_o oil_n be_v consume_v at_o e_o and_o the_o upper_a superficies_n thereof_o shall_v always_o be_v in_o the_o same_o horizontal_n line_n mm._n the_o geometrical_a and_o mechanical_a reason_n of_o which_o be_v so_o very_o plain_a i_o hope_v i_o shall_v not_o need_v to_o spend_v any_o more_o time_n in_o the_o explication_n thereof_o than_o only_o to_o say_v that_o by_o mean_n of_o the_o archimedean_a spiral-fusey_a the_o power_n of_o the_o weight_n i_o upon_o the_o pulley_n g_o decrease_v in_o the_o same_o proportion_n as_o the_o weight_n of_o the_o oil_n in_o the_o receptacle_n c_o c_o be_v diminish_v by_o its_o consumption_n the_o seven_o way_n than_o be_v by_o a_o cylindrical_a or_o prismatical_a plug_n fit_v into_o a_o cylindrical_a or_o prismatical_a receptacle_n and_o let_v down_o into_o it_o by_o a_o counterpoise_n hang_v upon_o a_o spiral_n fusey_n the_o oil_n be_v so_o raise_v in_o that_o receptacle_n as_o always_o to_o stand_v brimful_a or_o to_o the_o same_o horizontal_n height_n till_o the_o whole_a oil_n be_v consume_v the_o contrivance_n of_o this_o way_n will_v be_v very_o easy_o understand_v by_o any_o one_o that_o shall_v peruse_v the_o delineation_n in_o the_o eight_o figure_n and_o examine_v it_o by_o this_o follow_a description_n let_v a_o a_o in_o the_o eight_o figure_n then_o represent_v a_o cylindrical_a or_o prismatical_a receptacle_n stand_v fix_v upon_o a_o table_n or_o pedestal_n from_o the_o side_n of_o which_o issue_v a_o hollow_a arm_n or_o branch_n b_o b_o bear_v the_o socket_n for_o the_o wick_n c_o where_o the_o flame_n d_o be_v continue_v into_o the_o cavity_n of_o this_o receptacle_n be_v fit_v a_o cylindrical_a or_o prismatical_a plug_n e_o e_o big_a enough_o to_o fill_v the_o whole_a capacity_n thereof_o and_o yet_o not_o so_o close_o but_o that_o it_o may_v free_o slip_v up_o and_o down_o the_o cavity_n of_o the_o say_a receptacle_n without_o sink_v let_v this_o plug_n be_v make_v considerable_o heavy_a than_o the_o oil_n of_o the_o receptacle_n that_o be_v let_v the_o counterpoise_n l_o hang_v upon_o the_o little_a wheel_n m_o just_o reduce_v its_o gravity_n to_o be_v equal_a to_o that_o of_o the_o oil_n then_o let_v the_o point_n i_o where_o the_o perpendicular_a touch_v the_o spiral_n be_v so_o far_o remove_v from_o the_o centre_n of_o the_o wheel_n h_n that_o the_o counterpoise_n l_o may_v just_o take_v off_o its_o whole_a gravity_n and_o suffer_v it_o to_o have_v no_o degree_n of_o gravity_n or_o pressure_n downward_o then_o draw_v the_o spiral_n n_z o_o p_o according_a to_o the_o direction_n i_o give_v in_o the_o former_a way_n and_o the_o effect_n will_v be_v produce_v the_o geometrical_a and_o mechanical_a demonstration_n of_o which_o be_v very_o plain_a to_o any_o one_o that_o shall_v consider_v that_o as_o the_o plug_n e_o e_z by_o sink_v into_o the_o receptacle_n a_o a_o so_o far_o as_o to_o raise_v the_o oil_n to_o the_o horizontal_n superficies_n m_o
four_o as_o the_o root_n of_o 64._o that_o be_v of_o 19+17+15+13_n at_o the_o end_n of_o the_o ten_o or_o whole_a as_o the_o root_n of_o 100_o that_o be_v as_o equal_a to_o 100_o now_o since_o the_o velocity_n be_v in_o the_o same_o proportion_n to_o the_o root_n of_o the_o space_n as_o the_o root_n of_o the_o space_n be_v to_o the_o time_n it_o be_v easy_a to_o determine_v the_o particular_a time_n in_o which_o every_o one_o of_o these_o space_n be_v pass_v for_o divide_v the_o space_n by_o the_o velocity_n correspond_v the_o quotient_n give_v the_o particular_a time_n to_o explain_v this_o more_o intelligible_o let_v a_o in_o the_o four_o figure_n represent_v the_o end_n of_o a_o spring_n not_o bend_v or_o at_o least_o counterpoise_v in_o that_o posture_n by_o a_o power_n fix_v to_o it_o and_o movable_a with_o it_o draw_v the_o line_n a_o b_o c_o and_o let_v it_o represent_v the_o way_n in_o which_o the_o end_n of_o the_o spring_n by_o additional_a power_n be_v to_o be_v move_v draw_v to_o the_o end_n of_o it_o c_o at_o right_a angle_n the_o line_n c_o δ_n d_o d_o and_o let_v c_o d_o represent_v the_o power_n that_o be_v sufficient_a to_o bend_v or_o move_v the_o end_n of_o the_o spring_n a_o to_o c_o then_o draw_v the_o line_n d_o a_o and_o from_o any_o point_n of_o the_o line_n a_o c_o as_o b_o b._n draw_v line_n parallel_v to_o c_o d_o cut_v the_o line_n d_o a_o in_o e_o e_o the_o line_n b_o e_o b_o e_o will_v represent_v the_o respective_a power_n requisite_a to_o bend_v the_o end_n of_o the_o spring_n a_o to_o b_o which_o line_n b_o e_z b_o e_o c_o d_o will_n be_v in_o the_o same_o proportion_n with_o the_o length_n of_o the_o bent_n of_o the_o spring_n a_o b_o a_o b_o a_o c._n and_o because_o the_o spring_n have_v in_o every_o point_n of_o the_o line_n of_o bend_v a_o c_o a_o particular_a power_n therefore_o imagine_v infinite_a line_n draw_v from_o every_o point_n of_o a_o c_o parallel_n to_o c_o d_o till_o they_o touch_v the_o line_n a_o d_o they_o will_v all_o of_o they_o fill_v and_o compose_v the_o triangle_n a_o c_o d._n the_o triangle_n therefore_o a_o c_o d_o will_n represent_v the_o aggregate_v of_o the_o power_n of_o the_o spring_n bend_v from_o a_o to_o c_o and_o the_o lesser_a triangle_n a_o b_o e_o a_o b_o e_o will_n represent_v the_o aggregate_v of_o all_o the_o power_n of_o the_o spring_n bend_v from_o a_o to_o b_o b_o and_o the_o spring_n bend_v to_o any_o point_n of_o the_o line_n a_o c_o and_o let_v go_v from_o thence_o will_v exert_v in_o its_o return_n to_o a_o all_o those_o power_n which_o be_v equal_a to_o the_o respective_a ordinates_n b_o e_o b_o e_o in_o the_o triangle_n the_o sum_n of_o all_o which_o make_v up_o the_o triangle_n a_o b_o e_o a_o b_o e._n and_o the_o aggregate_v of_o the_o power_n with_o which_o it_o return_v from_o any_o point_n as_o from_o c_o to_o any_o point_n of_o the_o space_n c_o a_o as_o to_o b_o b_o be_v equal_a to_o the_o trapezium_fw-la c_o d_o e_o b_o c_o d_o e_o b_o or_o the_o excess_n of_o the_o great_a triangle_n above_o the_o less_o have_v therefore_o show_v a_o image_n to_o represent_v the_o flexure_n and_o the_o power_n so_o as_o plain_o to_o solve_v and_o answer_v all_o question_n and_o problem_n concern_v they_o in_o the_o next_o place_n i_o come_v to_o represent_v the_o velocity_n appropriate_v to_o the_o several_a power_n the_o velocity_n then_o be_v always_o in_o a_o subduplicate_v proportion_n of_o the_o power_n that_o be_v as_o the_o root_n of_o the_o power_n impress_v and_o the_o power_n impress_v be_v as_o the_o trapezium_fw-la or_o the_o excess_n of_o the_o triangle_n or_o square_n of_o the_o whole_a space_n to_o be_v pass_v above_o the_o square_n of_o the_o space_n yet_o unpassed_a if_o upon_o the_o centre_n a_o and_o space_n a_o c_o c_z being_z the_o point_n from_o which_o the_o spring_n be_v suppose_v let_v go_v a_o circle_n be_v describe_v as_o c_o g_o g_o f_o and_o ordinates_n draw_v from_o any_o point_n of_o c_o a_o the_o space_n to_o be_v past_a as_o from_o b_o b_o to_o the_o say_a circle_n as_o b_o g_z b_o g_o these_o line_n b_o g_z b_o g_o will_v represent_v the_o velocity_n of_o the_o spring_n return_v from_o c_o to_z b_o b_o etc._n etc._n the_o say_v ordinates_n being_n always_o in_o the_o same_o proportion_n with_o the_o root_n of_o the_o trapezium_n c_o d_o e_o b_o c_o d_o e_o b_o for_o putting_z a_o c_o =_o to_o a_o and_o a_o b_o =_o b_o b_o g_o will_n always_o be_v equal_a to_o the_o square_a of_o the_o ordinate_a be_v always_o equal_a to_o the_o rectangle_n of_o the_o intercept_a part_n of_o the_o diameter_n have_v thus_o find_v the_o velocity_n to_o wit_n b_o g_o b_o g_o a_o f_o to_o find_v the_o time_n correspond_v on_o the_o diameter_n a_o c_o draw_v a_o parabola_fw-la c_o h_o f_o who_o vertex_fw-la be_v c_o and_o which_o pass_v through_o the_o point_n f._n the_o ordinates_n of_o this_o parabola_fw-la b_o h_n b_o h_n a_o f_o be_v in_o the_o same_o proportion_n with_o the_o root_n of_o the_o space_n c_o b_o c_o b_o c_o a_o then_z making_z g_z b_o to_z h_z b_o as_o h_z b_o to_z ay_o b_o and_o through_o the_o point_n c_o i_o i_o f_o draw_v the_o curve_v c_z i_o i_o i_o f_o the_o respective_a ordinates_n of_o this_o curve_v shall_v represent_v the_o proportionate_a time_n that_o the_o spring_n spend_v in_o return_v the_o space_n c_o b_o c_o b_o c_o a._n if_o the_o power_n or_o stiffness_n of_o the_o spring_n be_v great_a than_o what_o i_o before_o suppose_v and_o therefore_o must_v be_v express_v by_o the_o triangle_n c_o de_fw-fr a._n then_o the_o velocity_n will_v be_v the_o ordinates_n in_o a_o ellipse_n as_o c_o γ_n γ_n n_n great_a than_o the_o circle_n as_o it_o will_v also_o if_o the_o power_n be_v the_o same_o and_o the_o bulk_n move_v by_o the_o spring_n be_v less_o then_o will_v the_o s-like_a line_n of_o time_n meet_v with_o the_o line_n a_o f_o at_o a_o point_n as_o x_o within_o the_o point_n f._n but_o if_o the_o power_n of_o the_o spring_n be_v weak_a than_o i_o suppose_v then_o will_v c_o δ_n e_o e_o a_o represent_v the_o power_n and_o c_o γ_n γ_n o_o the_o ellipsis_n of_o velocity_n who_o ordinates_n b_o γ_n b_o γ_n a_o o_o will_v give_v the_o particular_a velocity_n and_o the_o s-like_a line_n of_o time_n will_v extend_v beyond_o n._n the_o same_o will_v happen_v suppose_v the_o body_n move_v by_o the_o spring_n to_o be_v proportionate_o heavy_a and_o the_o power_n of_o the_o spring_n the_o same_o with_o the_o first_o and_o suppose_v the_o power_n of_o the_o spring_n the_o same_o as_o at_o first_o bend_v only_o to_o b_o 2_o and_o from_o thence_o let_v go_v b_o 2_o e_z a_o be_v the_o triangle_n of_o its_o power_n the_o ordinates_n of_o the_o circle_n b_o g_o l_o be_v the_o line_n of_o its_o velocity_n and_o the_o ordinates_n of_o the_o s-like_a line_n b_o i_o f_o be_v the_o live_v of_o time_n have_v thus_o show_v you_o how_o the_o velocity_n of_o a_o spring_n may_v be_v compute_v it_o will_v be_v easy_a to_o calculate_v to_o what_o distance_n it_o 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or_o space_n through_o which_o it_o pass_v a_o parabola_fw-la if_o the_o spring_n be_v bend_v to_o twice_o the_o former_a tension_n so_o as_o to_o deliver_v the_o body_n with_o double_a the_o velocity_n in_o a_o horizontal_n line_n that_o be_v with_o a_o velocity_n that_o move_v 32_o foot_n in_o a_o second_o then_o shall_v the_o body_n touch_v the_o floor_n in_o a_o point_n very_o near_o at_o 32_o foot_n from_o the_o aforesaid_a perpendicular_a point_n and_o the_o
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figure_n where_o the_o turn_v figure_n be_v cut_v in_o two_o part_n per_fw-la axin_n and_o whereof_o the_o axis_n be_v place_v horizontal_n and_o the_o plain_a section_n per_fw-la axin_o likewise_o horizontal_o so_o as_o it_o may_v be_v fill_v with_o any_o liquor_n up_o to_o that_o plain_a and_o that_o the_o liquor_n may_v not_o be_v apt_a to_o dash_v be_v shake_v or_o filter_n over_o it_o will_v be_v convenient_a to_o extend_v the_o brim_n of_o that_o receptacle_n somewhat_o above_o the_o half-round_a that_o there_o may_v be_v about_o half_a or_o three_o quarter_n of_o a_o inch_n of_o space_n above_o the_o superficies_n of_o the_o oil_n vacant_a or_o empty_a and_o that_o upon_o whatever_o plain_n the_o foot_n stand_v the_o plain_a per_fw-mi axin_o may_v stand_v horizontal_n it_o will_v be_v good_a to_o suspend_v the_o receptacle_n in_o the_o same_o manner_n as_o a_o seaman_n compass_n be_v suspend_v within_o a_o frame_n fix_v this_o receptacle_n or_o the_o frame_n that_o be_v to_o 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receptacle_n a_o neck_n and_o socket_n fit_a for_o the_o wick_n and_o flame_n of_o the_o lamp_n and_o the_o same_o operation_n will_v be_v perform_v by_o this_o as_o by_o the_o first_o contrivance_n to_o wit_n the_o oil_n will_v be_v keep_v always_o to_o the_o same_o height_n in_o the_o receptacle_n this_o will_v be_v easy_o understand_v by_o explain_v a_o designation_n thereof_o which_o be_v shadow_v forth_o in_o the_o four_o figure_n where_o a_o a_o a_o represent_v a_o pedestal_n which_o may_v be_v make_v with_o three_o claw_n or_o toe_n to_o make_v it_o stand_v the_o steady_a and_o even_a upon_o any_o plain_a or_o table_n b_o b_o represent_v one_o of_o the_o semicircular_a arm_n that_o be_v fix_v to_o the_o top_n of_o the_o pedestal_n this_o have_v two_o hole_n in_o it_o at_o the_o end_n or_o extremity_n as_o at_o c_o be_v one_o the_o other_o hole_n be_v in_o the_o other_o arm_n which_o go_v behind_o the_o globe_n and_o therefore_o can_v be_v see_v be_v suppose_v to_o be_v diametrical_o opposite_a to_o this_o at_o c._n these_o two_o hole_n be_v the_o centre_n hole_n in_o which_o two_o small_a pin_n or_o centre_n fasten_v into_o two_o opposite_a point_n of_o the_o hoop_n or_o frame_n be_v make_v fit_a to_o move_v by_o which_o mean_v the_o say_a hoop_n be_v preserve_v in_o a_o horizontal_a position_n d_o d_o be_v this_o hoop_n or_o frame_n which_o be_v make_v to_o encompass_v the_o vessel_n or_o receptacle_n of_o the_o oil_n and_o be_v shape_v exact_o like_o it_o this_o be_v make_v strong_a enough_o of_o brass_n iron_n silver_n or_o other_o material_a to_o bear_v the_o receptacle_n poise_n and_o oil_n without_o bend_v and_o have_v as_o i_o say_v before_o two_o pin_n or_o gudgeon_n at_o c_o and_o opposite_a to_o it_o diametrical_o or_o semicircular_o upon_o which_o the_o say_a hoop_n always_o hang_v horizontal_o it_o have_v also_o on_o each_o side_n in_o the_o middle_n between_o the_o aforesaid_a pivot_n two_o centre_n as_o at_o f_o and_o e_o to_o receive_v the_o end_n of_o the_o axis_n of_o the_o receptacle_n appear_v at_o f_o and_o e_o by_o which_o the_o say_a receptacle_n be_v always_o free_a to_o hang_v plumb_n or_o in_o its_o perpendicularity_n so_o as_o that_o the_o upper_a edge_n thereof_o at_o f_o f_o will_v always_o lie_v horizontal_o one_o of_o these_o pivot_n namely_o that_o on_o the_o right_a hand_n be_v the_o pipe_n to_o convey_v the_o oil_n to_o the_o socket_n of_o the_o lamp_n i_o in_o which_o be_v fit_v a_o wick_n of_o cotton_n to_o serve_v for_o the_o flame_n k_o g_o g_z represent_v the_o vessel_n or_o receptacle_n of_o oil_n which_o be_v here_o describe_v hemispherical_a that_o be_v the_o most_o capacious_a uniform_a figure_n but_o may_v be_v of_o any_o other_o qualify_v as_o those_o i_o mention_v in_o the_o first_o contrivance_n the_o brim_n of_o this_o be_v extend_v somewhat_o high_a than_o a_o semicircle_n namely_o to_o f_o f_o to_o keep_v the_o oil_n from_o flash_v or_o filter_v over_o this_o be_v always_o keep_v full_a with_o oil_n or_o other_o liquor_n to_o the_o horizontal_n prick_v line_n l_o l_o which_o pass_v through_o the_o centre_n or_o axis_n of_o its_o cavity_n by_o the_o counterpoise_n move_v on_o the_o centre_n c._n h_o h_n h_n represent_v that_o counterpoise_n which_o be_v make_v exact_o half_a the_o weight_n of_o the_o oil_n or_o liquor_n and_o the_o centre_n of_o gravity_n of_o it_o must_v be_v somewhere_o in_o the_o line_n m_o m_o and_o it_o ought_v to_o be_v fit_v as_o exact_o into_o the_o hollow_a of_o the_o receptacle_n as_o it_o be_v possible_a that_o there_o may_v be_v leave_v as_o little_a space_n as_o may_v be_v between_o its_o convex_a side_n and_o the_o concave_a of_o the_o receptacle_n
but_o yet_o so_o much_o must_v be_v leave_v that_o it_o may_v move_v very_o free_o upon_o its_o centre_n c_o a_o whole_a semicircle_n this_o do_v and_o the_o receptacle_n be_v fill_v with_o oil_n the_o same_o effect_n will_v follow_v as_o in_o the_o first_o contrivance_n and_o the_o demonstration_n of_o it_o be_v much_o the_o same_o i_o shall_v not_o now_o spend_v time_n to_o explain_v it_o but_o rather_o proceed_v to_o the_o description_n of_o a_o three_o way_n of_o keep_v the_o liquor_n counterpoise_v to_o the_o same_o level_n the_o three_o way_n than_o be_v take_v any_o round_a vessel_n who_o concavity_n and_o convexity_n be_v turn_v upon_o a_o axis_n and_o suspend_v that_o vessel_n upon_o two_o small_a pivot_n but_o yet_o big_a enough_o to_o bear_v the_o say_a vessel_n fill_v with_o oil_n etc._n etc._n fasten_v in_o the_o pole_n of_o that_o axis_n and_o leave_v or_o cut_v open_a a_o six_o part_v more_o or_o less_o as_o you_o please_v of_o the_o side_n thereof_o that_o thereby_o 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have_v to_o the_o superficies_n m_o l_o suppose_v there_o be_v no_o reflect_v superficies_n at_o e_o f._n i_o shall_v not_o need_v i_o hope_v more_o particular_o to_o demonstrate_v every_o part_n of_o this_o explanation_n the_o very_a observe_v the_o delineation_n of_o the_o scheme_n be_v enough_o to_o make_v it_o plain_a to_o any_o one_o never_o so_o little_o verse_v in_o geometry_n from_o which_o he_o will_v plain_o perceive_v that_o what_o i_o endeavour_v to_o demonstrate_v be_v real_o so_o and_o that_o i_o do_v understand_v what_o scope_n my_o demonstration_n aim_v at_o so_o far_o as_o to_o hit_v the_o mark_n which_o be_v to_o show_v that_o colour_n be_v generate_v where_o according_a to_o des_n cartes_n own_o principle_n there_o can_v be_v no_o rotation_n of_o the_o globuli_fw-la now_o though_o the_o learned_a doctor_n will_v not_o admit_v of_o this_o demonstration_n to_o be_v sufficient_a to_o do_v the_o work_n yet_o he_o say_v pag._n 252._o veruntamen_fw-la dissimulandum_fw-la non_fw-la est_fw-la non_fw-la pauca_fw-la i_o meapte_v opera_fw-la excogitasse_fw-la quibus_fw-la pro_fw-la persuasissimo_fw-la habeo_fw-la eorum_fw-la motus_fw-la &_o rotationes_fw-la modis_fw-la pure_a mechanicis_fw-la semper_fw-la fieri_fw-la non_fw-la posse_fw-la and_o in_o prosecution_n of_o the_o destruction_n of_o this_o rotation_n of_o the_o globuli_fw-la which_o he_o have_v hitherto_o seem_v to_o defend_v he_o add_v four_o several_a argument_n i_o shall_v not_o now_o stay_v to_o repeat_v they_o but_o whosoever_o will_v please_v to_o read_v what_o the_o learned_a doctor_n have_v suapte_v opera_fw-la excogitated_a against_o the_o cartesian_a hypothesis_n and_o set_v down_o in_o the_o 252_o 253_o 254_o and_o 255._o page_n and_o compare_v they_o with_o what_o i_o have_v say_v in_o the_o forementioned_a place_n to_o wit_n at_o the_o latter_a end_n of_o the_o 60._o and_o the_o beginning_n of_o the_o 61._o page_n of_o my_o micrographia_fw-la may_v plain_o find_v the_o argument_n 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