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
a_o syringe_n into_o the_o space_n fgb_n in_o that_o injection_n the_o air_n but_o pure_a air_n go_v with_o the_o same_o force_n out_o of_o the_o vessel_n through_o the_o injected_a water_n but_o as_o for_o those_o small_a body_n which_o former_o i_o suppose_v to_o be_v intermingle_v with_o air_n &_o to_o be_v move_v with_o simple_a motion_n they_o can_v not_o together_o with_o the_o our_o air_n penetrate_v the_o water_n but_o remain_v behind_o be_v necessary_o thrust_v together_o into_o a_o narrow_a place_n namely_o into_o the_o space_n which_o be_v above_o the_o water_n fg._n the_o motion_n therefore_o of_o those_o small_a body_n will_v be_v less_o and_o less_o free_a by_o how_o much_o the_o quantity_n of_o the_o injected_a water_n be_v great_a and_o great_a so_o that_o by_o their_o motion_n fall_v upon_o one_o another_o the_o same_o small_a body_n will_v mutual_o compress_v each_o other_o and_o have_v a_o perpetual_a endeavour_n of_o regayn_v their_o liberty_n and_o of_o depress_v the_o water_n that_o hinder_v they_o wherefore_o as_o soon_o as_o the_o orifice_n above_o be_v open_v the_o water_n which_o be_v next_o it_o will_v have_v a_o endeavour_n to_o ascend_v and_o will_v therefore_o necessary_o go_v out_o but_o it_o can_v go_v out_o unless_o at_o the_o same_o time_n there_o enter_v in_o as_o much_o air_n and_o therefore_o both_o the_o water_n will_v go_v out_o and_o the_o air_n enter_v in_o till_o those_o small_a body_n which_o be_v leave_v within_o the_o vessel_n have_v recover_v their_o former_a liberty_n of_o motion_n that_o be_v to_o say_v till_o the_o vessel_n be_v again_o fill_v with_o air_n and_o no_o water_n be_v leave_v of_o sufficient_a height_n to_o stop_v the_o passage_n at_o b._n wherefore_o i_o have_v show_v a_o possible_a cause_n of_o this_o phaenomenon_n namely_o the_o same_o with_o that_o of_o thunder_n for_o as_o in_o the_o generation_n of_o thunder_n the_o small_a body_n enclose_v within_o the_o cloud_n by_o be_v too_o close_o pen_v together_o do_v by_o their_o motion_n break_v the_o cloud_n and_o restore_v themselves_o to_o their_o natural_a liberty_n so_o here_o also_o the_o small_a body_n enclose_v within_o the_o space_n which_o be_v above_o the_o straight_a line_n fg_v do_v by_o their_o own_o motion_n expel_v the_o water_n as_o soon_o as_o the_o passage_n be_v open_v above_o and_o if_o the_o passage_n be_v keep_v stop_v and_o these_o small_a body_n be_v more_o vehement_o compress_v by_o the_o perpetual_a force_n in_o of_o more_o water_n they_o will_v at_o last_o break_v the_o vessel_n itself_o with_o great_a noise_n 10_o if_o aire_n be_v blow_v into_o a_o hollow_a cylinder_n or_o into_o a_o bladder_n it_o will_v increase_v the_o weight_n of_o either_o of_o they_o a_o little_a as_o many_o have_v find_v by_o experience_n who_o with_o great_a accurateness_n have_v try_v the_o same_o and_o it_o be_v no_o wonder_n see_v as_o i_o have_v suppose_v there_o be_v intermingle_v with_o the_o common_a air_n a_o great_a number_n of_o small_a hard_a body_n which_o be_v heavy_a than_o the_o pure_a air_n for_o the_o aethereal_a substance_n be_v on_o all_o side_n equal_o agitate_a by_o the_o motion_n of_o the_o sun_n have_v a_o equal_a endeavour_n towards_o all_o the_o part_n of_o the_o universe_n and_o therefore_o it_o have_v no_o gravity_n at_o all_o 11_o we_o find_v also_o by_o experience_n that_o by_o the_o force_n of_o air_n enclose_v in_o a_o hollow_a canon_n a_o bullet_n of_o lead_n may_v with_o considerable_a violence_n be_v shoot_v out_o of_o a_o gun_n of_o late_a invention_n call_v the_o windgun_n in_o the_o end_n of_o this_o canon_n there_o be_v two_o hole_n with_o their_o valve_n on_o the_o inside_n to_o shut_v they_o close_o one_o of_o they_o serve_v for_o the_o admission_n of_o air_n and_o the_o other_o for_o the_o let_n of_o it_o out_o also_o to_o that_o end_n which_o serve_v for_o the_o receive_n in_o of_o air_n there_o be_v join_v another_o canon_n of_o the_o same_o metal_n and_o bigness_n in_o which_o there_o be_v fit_v a_o rammer_n which_o be_v perforate_v and_o have_v also_o a_o valve_n open_v towards_o the_o former_a canon_n by_o the_o help_n of_o this_o valve_n the_o rammer_n be_v easy_o draw_v back_o and_o let_v in_o air_n from_o without_o and_o be_v often_o draw_v back_o and_o return_v again_o with_o violent_a stroke_n it_o force_v some_o part_n of_o that_o air_n into_o the_o former_a canon_n so_o long_o till_o at_o last_o the_o resistance_n of_o the_o enclose_a air_n be_v great_a than_o the_o force_n of_o the_o stroke_n and_o by_o this_o mean_n man_n think_v there_o be_v now_o a_o great_a quantity_n of_o air_n in_o the_o canon_n then_o there_o be_v former_o though_o it_o be_v full_a before_o also_o the_o air_n thus_o force_v in_o how_o much_o soever_o it_o be_v be_v hinder_v from_o get_v out_o again_o by_o the_o foresay_a valve_n which_o the_o very_a endeavour_n of_o the_o air_n to_o get_v out_o do_v necessary_o shut_v last_o that_o valve_n be_v open_v which_o be_v make_v for_o the_o let_v out_o of_o the_o air_n it_o present_o break_v out_o with_o violence_n &_o drive_v the_o bullet_n before_o it_o with_o great_a force_n and_o velocity_n as_o for_o the_o cause_n of_o this_o i_o can_v easy_o attribute_v it_o as_o most_o man_n do_v to_o condensation_n and_o think_v that_o the_o air_n which_o have_v at_o the_o first_o but_o its_o ordinary_a degree_n of_o rarity_n be_v afterward_o by_o the_o force_n in_o of_o more_o air_n condense_v and_o last_o of_o all_o rarefy_v again_o by_o be_v let_v out_o and_o restore_v to_o its_o natural_a liberty_n but_o i_o can_v imagine_v how_o the_o same_o place_n can_v be_v always_o full_a and_o nevertheless_o contain_v sometime_o a_o great_a sometime_o a_o less_o quantity_n of_o matter_n that_o be_v to_o say_v that_o it_o can_v be_v full_a than_o full_a nor_o can_v i_o conceive_v how_o fullness_n can_v of_o itself_o be_v a_o efficient_a cause_n of_o motion_n for_o both_o â—hese_n be_v impossible_a wherefore_o we_o must_v seek_v out_o some_o other_o possible_a cause_n of_o this_o phaenomenon_n whilst_o therefore_o the_o valve_n with_o ch_n serve_v for_o the_o let_n in_o of_o air_n be_v open_v by_o the_o first_o stroke_n of_o the_o rammer_n the_o air_n within_o do_v with_o equal_a force_n resist_v the_o enter_n of_o the_o air_n from_o without_o so_o that_o the_o endeavour_n between_o the_o internal_a and_o external_a air_n be_v opposite_a that_o be_v there_o be_v two_o opposite_a motion_n while_o the_o one_o go_v in_o and_o the_o other_o come_v out_o but_o no_o augmentation_n at_o all_o of_o air_n within_o the_o canon_n for_o there_o be_v drive_v out_o by_o the_o stroke_n as_o much_o pure_a air_n which_o pass_v between_o the_o rammer_n and_o the_o side_n of_o the_o canon_n as_o there_o be_v force_v in_o of_o air_n impure_a by_o the_o same_o stroke_n and_o thus_o by_o many_o forcible_a stroke_n the_o quantity_n of_o small_a hard_a body_n will_v be_v increase_v within_o the_o canon_n and_o their_o motion_n also_o will_v grow_v strong_a and_o strong_a as_o long_a as_o the_o matter_n of_o the_o canon_n be_v able_a to_o endure_v their_o force_n by_o which_o if_o it_o be_v not_o break_v it_o will_v at_o least_o be_v urge_v every_o way_n by_o their_o endeavour_n to_o free_v themselves_o and_o as_o soon_o as_o the_o valve_n which_o serve_v to_o let_v they_o out_o be_v open_v they_o will_v fly_v out_o with_o violent_a motion_n and_o carry_v with_o they_o the_o bullet_n which_o be_v in_o their_o way_n wherefore_o i_o have_v give_v a_o possible_a cause_n of_o this_o phaenomenon_n 12_o water_n contrary_a to_o the_o custom_n of_o heavy_a body_n ascend_v in_o the_o weatherglass_n but_o it_o do_v it_o when_o the_o air_n be_v cold_a for_o when_o it_o be_v warm_v it_o descend_v again_o and_o this_o organ_n be_v call_v a_o thermometer_n or_o thermoscope_n because_o the_o degree_n of_o heat_n and_o cold_a be_v measure_v and_o mark_v by_o it_o it_o be_v make_v in_o this_o manner_n let_v a_o b_o c_o d_o in_o the_o 5_o figure_n be_v a_o vessel_n full_a of_o water_n and_o e_o f_o g_o a_o hollow_a cylinder_n of_o glass_n close_v at_o e_o and_o open_a at_o g._n let_v it_o be_v heat_v and_o set_v upright_o within_o the_o water_n to_o f_o and_o let_v the_o open_a end_n reach_v to_o g._n this_o be_v do_v as_o the_o air_n by_o little_a and_o little_o grow_v cold_a the_o water_n will_v ascend_v slow_o within_o the_o cylinder_n from_o f_o towards_o e_z till_o at_o last_o the_o external_a and_o internal_a air_n come_v to_o be_v both_o of_o the_o same_o temper_n it_o will_v neither_o ascend_v high_a nor_o descend_v low_o till_o the_o temper_n of_o the_o air_n be_v change_v suppose_v it_o therefore_o
to_o be_v settle_v any_o where_o as_o at_o h._n if_o now_o the_o heat_n of_o the_o air_n be_v augment_v the_o water_n will_v descend_v below_o h_n and_o if_o the_o heat_n be_v diminish_v it_o will_v ascend_v above_o it_o which_o though_o it_o be_v certain_o know_v to_o be_v true_a by_o experience_n the_o cause_n nevertheless_o have_v not_o as_o yet_o be_v discover_v in_o the_o 6_o and_o 7_o article_n of_o the_o 27_o chapter_n where_o i_o consider_v the_o cause_n of_o cold_a i_o have_v show_v that_o fluid_a body_n be_v make_v cold_a by_o the_o pressure_n of_o the_o air_n that_o be_v to_o say_v by_o a_o constant_a wind_n that_o press_v they_o for_o the_o same_o cause_n it_o be_v that_o the_o superficies_n of_o the_o water_n be_v press_v at_o f_o and_o have_v no_o place_n to_o which_o it_o may_v retire_v from_o this_o pressure_n beside_o the_o cavity_n of_o the_o cylinder_n between_o h_n and_o e_o it_o be_v therefore_o necessary_o force_v thither_o by_o the_o cold_a and_o consequent_o it_o ascend_v more_o or_o less_o according_a as_o the_o cold_a be_v more_o or_o less_o increase_v and_o again_o as_o the_o heat_n be_v more_o intense_a or_o the_o cold_a more_o remiss_a the_o same_o water_n will_v be_v depress_v more_o or_o less_o by_o its_o own_o gravity_n that_o be_v to_o say_v by_o the_o cause_n of_o gravity_n above_o explicate_v 13_o also_o live_v creature_n though_o they_o be_v heavy_a can_v by_o leap_v swim_v &_o fly_v raise_v themselves_o to_o a_o certain_a degree_n of_o height_n but_o they_o can_v do_v this_o except_o they_o be_v support_v by_o some_o resist_a body_n as_o the_o earth_n the_o water_n and_o the_o air_n for_o these_o motion_n have_v their_o beginning_n from_o the_o contraction_n by_o the_o help_n of_o the_o muscle_n of_o the_o body_n animate_v for_o to_o this_o contraction_n there_o succee_v a_o distension_n of_o their_o whole_a body_n by_o which_o distension_n the_o earth_n the_o water_n or_o the_o air_n which_o support_v they_o be_v press_v and_o from_o hence_o by_o the_o reaction_n of_o those_o press_a body_n live_v creature_n acquire_v a_o endeavour_n upward_o but_o such_o as_o by_o reason_n of_o the_o gravity_n of_o their_o body_n be_v present_o lose_v again_o by_o this_o endeavour_n therefore_o it_o be_v that_o live_v creature_n raise_v themselves_o up_o a_o little_a way_n by_o leap_v but_o to_o no_o great_a purpose_n but_o by_o swim_v &_o fly_v they_o raise_v themselves_o to_o a_o great_a height_n because_o before_o the_o effect_n of_o their_o endeavour_n be_v quite_o extinguish_v by_o the_o gravity_n of_o their_o body_n they_o can_v renew_v the_o same_o endeavour_n again_o that_o by_o the_o power_n of_o the_o soul_n without_o any_o antecedent_n contraction_n of_o the_o muscle_n or_o the_o help_n of_o something_o to_o support_v he_o any_o man_n can_v be_v able_a to_o raise_v his_o body_n upward_o be_v a_o childish_a conceit_n for_o if_o it_o be_v true_a a_o man_n may_v raise_v himself_o to_o what_o height_n he_o please_v 14_o the_o diaphanous_a medium_fw-la which_o surround_v the_o eye_n on_o all_o fides_fw-la be_v invisible_a nor_o be_v air_n to_o be_v see_v in_o air_n nor_o water_n in_o water_n nor_o any_o thing_n but_o that_o which_o be_v more_o opacous_a but_o in_o the_o confine_n of_o two_o diaphanous_a body_n one_o of_o they_o may_v be_v distinguish_v from_o the_o other_o it_o be_v not_o therefore_o a_o thing_n so_o very_o ridiculous_a for_o ordinary_a people_n to_o think_v all_o that_o space_n empty_a in_o which_o we_o say_v be_v air_n it_o be_v the_o work_n of_o reason_n to_o make_v we_o conceive_v that_o the_o air_n be_v any_o thing_n for_o by_o which_o of_o our_o sense_n be_v it_o that_o we_o take_v notice_n of_o the_o air_n see_v we_o neither_o see_v nor_o hear_v nor_o taste_n nor_o smell_v nor_o feel_v it_o to_o be_v any_o thing_n when_o we_o feel_v heat_n we_o do_v not_o impute_v it_o to_o the_o air_n but_o to_o the_o fire_n nor_o do_v we_o say_v the_o air_n be_v cold_a but_o we_o ourselves_o be_v cold_a and_o when_o we_o feel_v the_o wind_n we_o rather_o think_v something_o be_v come_v then_o that_o any_o thing_n be_v already_o come_v also_o we_o do_v not_o at_o all_o feel_v the_o weight_n of_o water_n in_o water_n much_o less_o of_o air_n in_o air_n that_o we_o come_v to_o know_v that_o to_o be_v a_o body_n which_o we_o call_v air_n it_o be_v by_o reason_v but_o it_o be_v from_o one_o reason_n only_o namely_o because_o it_o be_v impossible_a for_o remote_a body_n to_o work_v upon_o our_o organ_n of_o sense_n but_o by_o the_o help_n of_o body_n intermediate_v without_o which_o we_o can_v have_v no_o sense_n of_o they_o till_o they_o come_v to_o be_v contiguous_a wherefore_o from_o the_o sense_n alone_o without_o reason_v from_o effect_n we_o can_v have_v sufficient_a evidence_n of_o the_o nature_n of_o body_n for_o there_o be_v underground_o in_o some_o mine_n of_o coal_n a_o certain_a matter_n of_o a_o middle_a nature_n between_o water_n and_o aire_n which_o nevertheless_o can_v by_o sense_n be_v distinguish_v from_o air_n for_o it_o be_v as_o diaphanous_a as_o the_o pure_a air_n and_o as_o far_o as_o sense_n can_v judge_v equal_o penetrable_a but_o if_o we_o look_v upon_o the_o effect_n it_o be_v like_a that_o of_o water_n for_o when_o that_o matter_n break_v out_o of_o the_o earth_n into_o one_o of_o those_o pit_n it_o fill_v the_o same_o either_o total_o or_o to_o some_o degree_n and_o if_o a_o man_n or_o fire_n be_v then_o let_v down_o into_o it_o it_o extinguish_v they_o in_o almost_o as_o little_a time_n as_o water_n will_v do_v but_o for_o the_o better_a understanding_n of_o this_o phaenomenon_n i_o shall_v describe_v the_o 6_o figure_n in_o which_o let_v a_o b_o represent_v the_o pit_n of_o the_o mine_n and_o let_v part_n thereof_o namely_o c_o b_o be_v suppose_v to_o be_v fill_v with_o that_o matter_n if_o now_o a_o light_a candle_n be_v let_v down_o into_o it_o below_o c_o it_o will_v as_o sudden_o be_v extinguish_v as_o if_o it_o be_v thrust_v into_o water_n also_o if_o a_o grate_n fill_v with_o coal_n thorough_o kindle_v and_o burn_v never_o so_o bright_o be_v let_v down_o as_o soon_o as_o ever_o it_o be_v below_o c_o the_o fire_n will_v begin_v to_o grow_v pale_a and_o short_o after_o lose_v its_o light_n be_v extinguish_v no_o otherwise_o then_o if_o it_o be_v quench_v in_o water_n but_o if_o the_o grate_n be_v draw_v up_o again_o present_o while_o the_o coal_n be_v still_o very_o hot_a the_o fire_n will_v by_o little_a and_o little_o be_v kindle_v again_o and_o shine_v as_o before_o there_o be_v indeed_o between_o this_o matter_n &_o water_v this_o considerable_a difference_n that_o it_o neither_o wet_v nor_o stick_v to_o such_o thing_n as_o be_v put_v down_o into_o it_o as_o water_n do_v which_o by_o the_o moisture_n it_o leave_v hinder_v the_o kindle_v again_o of_o the_o matter_n once_o extinguish_v in_o like_a manner_n if_o a_o man_n be_v let_v down_o below_o c_o he_o will_v present_o fall_v into_o a_o great_a difficulty_n of_o breathe_v and_o immediate_o after_o into_o a_o swoon_n and_o die_v unless_o he_o be_v sudden_o draw_v up_o again_o they_o therefore_o that_o go_v down_o into_o these_o pit_n have_v this_o custom_n that_o as_o soon_o as_o ever_o they_o feel_v themselves_o sick_a they_o shake_v the_o rope_n by_o which_o they_o be_v let_v down_o to_o signify_v they_o be_v not_o well_o and_o to_o the_o end_n that_o they_o may_v speedy_o be_v pull_v up_o again_o for_o if_o a_o man_n be_v draw_v out_o too_o late_a void_a of_o sense_n and_o motion_n they_o dig_v up_o a_o turf_n and_o put_v his_o face_n and_o mouth_n into_o the_o fresh_a earth_n by_o which_o mean_v unless_o he_o be_v quite_o dead_a he_o come_v to_o himself_o again_o by_o little_a and_o little_a and_o recover_v life_n by_o the_o breathe_n out_o as_o it_o be_v of_o that_o suffocate_a matter_n which_o he_o have_v suck_v in_o while_o he_o be_v in_o the_o pit_n almost_o in_o the_o same_o manner_n as_o they_o that_o be_v drown_v come_v to_o themselves_o again_o by_o vomit_v up_o the_o water_n but_o this_o do_v not_o happen_v in_o all_o mine_n but_o in_o some_o only_o and_o in_o those_o not_o always_o but_o often_o in_o such_o pit_n as_o be_v subject_a to_o it_o they_o use_v this_o remedy_n they_o dig_v another_o pit_n as_o de_fw-fr close_o by_o it_o of_o equal_a depth_n and_o join_v they_o both_o together_o with_o one_o common_a channel_n of_o they_o make_v a_o fire_n in_o the_o bottom_n e_o which_o carry_v out_o at_o d_o the_o air_n contain_v in_o the_o pit_n de_fw-fr and_o this_o draw_v with_o it_o the_o air_n contain_v in_o the_o channel_n of_o which_o
axis_n ig_n the_o same_o with_o bc_n depart_v from_o its_o own_o former_a situation_n wherefore_o in_o what_o time_n bc_n come_v to_o ig_v by_o the_o motion_n from_o b_o to_o i_o upon_o the_o centre_n a_o in_o the_o same_o time_n g_o will_v come_v to_o f_o by_o the_o contrary_a motion_n of_o the_o epicycle_n that_o be_v it_o will_v be_v turn_v backward_o to_o f_o &_o ig_n will_v lie_v in_o if_o but_o the_o angle_n fig_n and_o gac_n be_v equal_a and_o therefore_o ac_fw-la that_o be_v bc_n and_o ig_a that_o be_v the_o axis_n though_o in_o different_a place_n will_v be_v parallel_n wherefore_o the_o axis_n of_o the_o epicycle_n edc_n will_v be_v carry_v always_o parallel_v to_o itself_o which_o be_v to_o be_v prove_v coral_n from_o hence_o it_o be_v manifest_a that_o those_o two_o annual_a motion_n which_o copernicus_n ascribe_v to_o the_o earth_n be_v reducible_a to_o this_o one_o circular_a simple_a motion_n by_o which_o all_o the_o point_n of_o the_o move_v body_n be_v carry_v always_o with_o equal_a velocity_n that_o be_v in_o equal_a time_n they_o make_v equal_a revolution_n uniform_o this_o as_o it_o be_v the_o most_o simple_a so_o it_o be_v the_o most_o frequent_a of_o all_o circular_a motion_n be_v the_o same_o which_o be_v use_v by_o all_o man_n when_o they_o turn_v any_o thing_n round_o with_o their_o arm_n as_o they_o do_v in_o grind_v or_o sift_v for_o all_o the_o point_n of_o the_o thing_n move_v describe_v line_n which_o be_v like_a and_o equal_a to_o one_o another_o so_o that_o if_o a_o man_n have_v a_o ruler_n in_o which_o many_o pen_n point_n of_o equal_a length_n be_v fasten_v he_o may_v with_o this_o one_o motion_n write_v many_o line_n at_o once_o 3_o have_v show_v what_o simple_a motion_n be_v i_o will_v here_o also_o set_v down_o some_o property_n of_o the_o same_o first_o when_o a_o body_n be_v move_v with_o simple_a motion_n in_o a_o fluid_fw-la medium_fw-la which_o have_v no_o vacuity_n it_o change_v the_o situation_n of_o all_o the_o part_n of_o the_o fluid_fw-la ambient_fw-la which_o resist_v its_o motion_n i_o say_v there_o be_v no_o part_n so_o small_a of_o the_o fluid_fw-la ambient_fw-la how_o far_o soever_o it_o be_v continue_v but_o do_v change_v their_o situation_n in_o such_o manner_n as_o that_o they_o leave_v their_o place_n continual_o to_o other_o small_a part_n that_o come_v into_o the_o same_o for_o in_o the_o same_o second_o figure_n let_v any_o body_n as_o klmn_n be_v understand_v to_o be_v move_v with_o simple_a circular_a motion_n and_o let_v the_o circle_n which_o every_o point_n thereof_o describe_v have_v any_o determine_a quantity_n suppose_v that_o of_o the_o same_o klmn_n wherefore_o the_o centre_n a_o and_o every_o other_o point_n and_o consequent_o the_o move_a body_n itself_o will_v be_v carry_v sometime_o towards_o the_o side_n where_o be_v k_o and_o sometime_o towards_o the_o other_o side_n where_o be_v m._n when_o therefore_o it_o be_v carry_v to_o k_o the_o part_n of_o the_o fluid_fw-la medium_fw-la on_o that_o side_n will_v go_v back_o and_o suppose_v all_o space_n to_o be_v full_a other_o on_z the_o other_o side_n will_v succeed_v and_o so_o it_o will_v be_v when_o the_o body_n be_v carry_v to_o the_o side_n m_o and_o to_o n_o and_o every_o way_n now_o when_o the_o near_a part_n of_o the_o fluid_fw-la medium_fw-la go_v back_n it_o be_v necessary_a that_o the_o part_n next_o to_o those_o near_a part_n go_v back_o also_o and_o suppose_v still_o all_o space_n to_o be_v full_a other_o part_n will_v come_v into_o their_o place_n with_o succession_n perpetual_a and_o infinite_a wherefore_o all_o even_o the_o least_o part_n of_o the_o fluid_fw-la medium_fw-la change_n their_o place_n etc._n etc._n which_o be_v to_o be_v prove_v it_o be_v evident_a from_o hence_o that_o simple_a motion_n whether_o circular_a or_o not_o circular_a of_o body_n which_o make_v perpetual_a return_n to_o their_o former_a place_n have_v great_a or_o less_o force_v to_o dissipate_v the_o part_n of_o resist_a body_n as_o it_o be_v more_o or_o less_o swift_a and_o as_o the_o line_n describe_v have_v great_a or_o less_o magnitude_n now_o the_o great_a velocity_n that_o can_v be_v may_v be_v understand_v to_o be_v in_o the_o least_o circuit_n and_o the_o least_o in_o the_o great_a and_o may_v be_v so_o suppose_v when_o there_o be_v need_n 4_o second_o suppose_v the_o same_o simple_a motion_n in_o the_o air_n water_n or_o other_o fluid_fw-la medium_fw-la the_o part_n of_o the_o medium_fw-la which_o adhere_v to_o the_o move_v body_n will_v be_v carry_v about_o with_o the_o same_o motion_n and_o velocity_n so_o that_o in_o what_o time_n soever_o any_o point_n of_o the_o movent_fw-la finish_v its_o circle_n in_o the_o same_o time_n every_o part_n of_o the_o medium_fw-la which_o adhere_v to_o the_o movent_fw-la shall_v also_o describe_v such_o a_o part_n of_o its_o circle_n as_o be_v equal_a to_o the_o whole_a circle_n of_o the_o movent_fw-la i_o say_v it_o shall_v describe_v a_o part_n and_o not_o the_o whole_a circle_n because_o all_o its_o part_n receive_v their_o motion_n from_o a_o interior_a concentrique_fw-la movent_fw-la and_o of_o concentrique_fw-la circle_n the_o exterior_a be_v always_o great_a than_o the_o interior_a nor_o can_v the_o motion_n imprint_v by_o any_o movent_fw-la be_v of_o great_a velocity_n then_o that_o of_o the_o movent_fw-la itself_o from_o whence_o it_o follow_v that_o the_o more_o remote_a part_n of_o the_o fluid_fw-la ambient_fw-la shall_v finish_v their_o circle_n in_o time_n which_o have_v to_o one_o another_o the_o same_o proportion_n with_o their_o distance_n from_o the_o movent_fw-la for_o every_o point_n of_o the_o fluid_fw-la ambient_fw-la as_o long_o as_o it_o touch_v the_o body_n which_o carry_v it_o about_o be_v carry_v about_o with_o it_o and_o will_v make_v the_o same_o circle_n but_o that_o it_o be_v leave_v behind_o so_o much_o as_o the_o exterior_a circle_n exceed_v the_o interior_a so_o that_o if_o we_o suppose_v some_o thing_n which_o be_v not_o fluid_a to_o float_v in_o that_o part_n of_o the_o fluid_fw-la ambient_fw-la which_o be_v near_a to_o the_o movent_fw-la it_o will_v together_o with_o the_o movent_fw-la be_v carry_v about_o now_o that_o part_n of_o the_o fluid_fw-la ambient_fw-la which_o be_v not_o the_o near_a but_o almost_o the_o near_a receive_v its_o degree_n of_o velocity_n from_o the_o near_a which_o degree_n can_v be_v great_a than_o it_o be_v in_o the_o giver_n do_v therefore_o in_o the_o same_o time_n make_v a_o circular_a line_n not_o a_o whole_a circle_n yet_o equal_a to_o the_o whole_a circle_n of_o the_o near_a therefore_o in_o the_o same_o time_n that_o the_o movent_fw-la describe_v its_o circle_n that_o which_o do_v not_o touch_v it_o shall_v not_o describe_v its_o circle_n yet_o it_o shall_v describe_v such_o a_o part_n of_o it_o as_o be_v equal_a to_o the_o whole_a circle_n of_o the_o movent_fw-la and_o after_o the_o same_o manner_n the_o more_o remote_a part_n of_o the_o ambient_fw-la will_v describe_v in_o the_o same_o time_n such_o part_n of_o their_o circle_n as_o shall_v be_v several_o equal_a to_o the_o whole_a circle_n of_o the_o movent_fw-la and_o by_o consequent_a they_o shall_v finish_v their_o whole_a circle_n in_o time_n proportional_a to_o their_o distance_n from_o the_o movent_fw-la which_o be_v to_o be_v prove_v 5_o three_o the_o same_o simple_a motion_n of_o a_o body_n place_v in_o a_o fluid_fw-la medium_fw-la congregate_n or_o gather_v into_o one_o place_n such_o thing_n as_o natural_o float_v in_o that_o medium_fw-la if_o they_o be_v homogeneous_a and_o if_o they_o be_v heterogeneous_a it_o separate_v and_o dissipate_v they_o but_o if_o such_o thing_n as_o be_v heterogeneous_a do_v not_o float_v but_o settle_v than_o the_o same_o motion_n stir_v and_o mingle_v they_o disorderly_a together_o for_o see_v body_n which_o be_v unlike_a to_o one_o another_o that_o be_v heterogeneous_a body_n be_v not_o unlike_a in_o that_o they_o be_v body_n for_o body_n as_o body_n have_v no_o difference_n but_o only_a from_o some_o special_a cause_n that_o be_v from_o some_o internal_a motion_n or_o motion_n of_o their_o small_a part_n for_o i_o have_v show_v in_o the_o 9th_o chapter_n and_o 9th_o article_n that_o all_o mutation_n be_v such_o motion_n it_o remain_v that_o heterogeneous_a body_n have_v their_o unlikeness_n or_o difference_n from_o one_o another_o from_o their_o internal_a or_o specifical_a motion_n now_o body_n w_z ch_n have_v such_o difference_n receive_v unlike_a &_o different_a motion_n from_o the_o same_o external_a common_a movent_fw-la and_o therefore_o they_o will_v not_o be_v move_v together_o that_o be_v to_o say_v they_o will_v be_v dissipate_v and_o be_v dissipate_v they_o will_v necessary_o at_o some_o time_n or_o other_o meet_v with_o body_n like_o themselves_o and_o be_v move_v
nor_o can_v they_o go_v direct_o backward_o against_o the_o force_n of_o the_o movent_fw-la it_o remain_v therefore_o that_o they_o diffuse_v themselves_o upon_o the_o superficies_n of_o that_o body_n as_o towards_o o_o and_o p_o which_o be_v to_o be_v prove_v 9_o compound_v circular_a motion_n in_o which_o all_o the_o part_n of_o the_o move_v body_n do_v at_o once_o describe_v circumference_n some_o great_a other_o less_o according_a to_o the_o proportion_n of_o their_o several_a distance_n from_o the_o common_a centre_n carry_v about_o with_o it_o such_o body_n as_o be_v not_o fluid_a adhere_v to_o the_o body_n so_o move_v and_o such_o as_o do_v not_o adhere_v it_o cast_v forward_o in_o a_o straight_a line_n which_o be_v a_o tangent_fw-la to_o the_o point_n from_o which_o they_o be_v cast_v off_o for_o let_v there_o be_v a_o circle_n who_o radius_fw-la be_v ab_fw-la in_o the_o four_o figure_n and_o let_v a_o body_n be_v place_v in_o the_o circumference_n in_o b_o which_o if_o it_o be_v fix_v there_o will_v necessary_o be_v carry_v about_o with_o it_o as_o be_v manifest_a of_o itself_o but_o while_o the_o motion_n proceed_v let_v we_o suppose_v that_o body_n to_o be_v unfixed_a in_o b._n i_o say_v the_o body_n will_v continue_v its_o motion_n in_o the_o tangent_fw-la bc._n for_o let_v both_o the_o radius_fw-la ab_fw-la and_o the_o sphere_n b_o be_v conceive_v to_o consist_v of_o hard_a matter_n and_o let_v we_o suppose_v the_o radius_fw-la ab_fw-la to_o be_v strike_v in_o the_o point_n b_o by_o some_o other_o body_n which_o fall_v upon_o it_o in_o the_o tangent_fw-la db._n now_o therefore_o there_o will_v be_v a_o motion_n make_v by_o the_o concourse_n of_o two_o thing_n the_o one_o endeavour_v towards_o c_o in_o the_o straight_a line_n db_v produce_v in_o which_o the_o body_n b_o will_v proceed_v if_o it_o be_v not_o retain_v by_o the_o radius_fw-la ab_fw-la the_o other_z the_o retention_n itself_o but_o the_o retention_n alone_o cause_v no_o endeavour_n towards_o the_o centre_n and_o therefore_o the_o retention_n be_v take_v away_o which_o be_v do_v by_o the_o unfix_v of_o b_o there_o will_v remain_v but_o one_o endeavour_n in_o b_o namely_o that_o in_o the_o tangent_fw-la bc._n wherefore_o the_o motion_n of_o the_o body_n b_o unfixed_a will_v proceed_v in_o the_o tangent_fw-la bc_n which_o be_v to_o be_v prove_v by_o this_o demonstration_n it_o be_v manifest_a that_o circular_a motion_n about_o a_o unmoved_a axis_n shake_v off_o and_o put_v further_a from_o the_o centre_n of_o its_o motion_n such_o thing_n as_o touch_v but_o do_v not_o stick_v fast_o to_o its_o superficies_n and_o the_o more_o by_o how_o much_o the_o distance_n be_v great_a from_o the_o pole_n of_o the_o circular_a motion_n and_o so_o much_o the_o more_o also_o by_o how_o much_o the_o thing_n that_o be_v shake_v off_o be_v less_o drive_v towards_o the_o centre_n by_o the_o fluid_fw-la ambient_fw-la for_o other_o cause_n 10_o if_o in_o a_o fluid_fw-la medium_fw-la a_o spherical_a body_n be_v move_v with_o simple_a circular_a motion_n and_o in_o the_o same_o medium_fw-la there_o float_v another_o sphere_n who_o matter_n be_v not_o fluid_a this_o sphere_n also_o shall_v be_v move_v with_o simple_a circular_a motion_n let_v bcd_n in_o the_o 5_o figure_n be_v a_o circle_n who_o centre_n be_v a_o and_o in_o who_o circumference_n there_o be_v a_o sphere_n so_o move_v that_o it_o describe_v with_o simple_a motion_n the_o perimeter_n bcd_n let_v also_o efg_o be_v another_o sphere_n of_o consistent_a matter_n who_o semidiameter_n be_v eh_n and_o centre_n h_n and_o with_o the_o radius_fw-la ah_o let_v the_o circle_n he_o be_v describe_v i_o say_v the_o sphere_n efg_v will_v by_o the_o motion_n of_o the_o body_n in_o bcd_n be_v move_v in_o the_o circumference_n he_o with_o simple_a motion_n for_o see_v the_o motion_n in_o bcd_n by_o the_o four_o article_n of_o this_o chapter_n make_v all_o the_o point_n of_o the_o fluid_fw-la medium_fw-la describe_v in_o the_o same_o time_n circular_a line_n equal_a to_o one_o another_o the_o points_z e_z h_z and_o g_z of_o the_o straight_a line_n ehg_v will_n in_o the_o same_o time_n describe_v with_o equal_a radii_fw-la equal_a circle_n let_v ebb_n be_v draw_v equal_a and_o parallel_v to_o the_o straight_a line_n ah_o and_o let_v ab_fw-la be_v connect_v which_o will_v therefore_o be_v equal_a and_o parallel_v to_o eh_n and_o therefore_o also_o if_o upon_o the_o centre_n b_o and_o radius_fw-la be_v the_o arch_n eke_o be_v draw_v equal_a to_o the_o arch_n he_o and_o the_o straight_a line_n a_z bk_n and_o ik_fw-mi be_v draw_v bk_n and_o ai_fw-fr will_v be_v equal_a and_o they_o will_v also_o be_v parallel_n because_o the_o two_o arch_n eke_o and_o he_o that_o be_v the_o two_o angle_n kbe_n and_o jah_n be_v equal_a and_o consequent_o the_o straight_a line_n ab_fw-la and_o ki_v which_o connect_v they_o will_v also_o be_v equal_a and_o parallel_v wherefore_o ki_n and_o eh_n be_v parallel_n see_v therefore_o e_z and_o h_n be_v carry_v in_o the_o same_o time_n to_o k_o and_o i_o the_o whole_a straight_a line_n ik_fw-mi will_v be_v parallel_n to_o eh_n from_o whence_o it_o depart_v and_o therefore_o see_v the_o sphere_n efg_n be_v suppose_v to_o be_v of_o consistent_a matter_n so_o as_o all_o its_o point_n keep_v always_o the_o same_o situation_n it_o be_v necessary_a that_o every_o other_o straight_a line_n take_v in_o the_o same_o sphere_n be_v carry_v always_o parallel_v to_o the_o place_n in_o which_o it_o former_o be_v wherefore_o the_o sphere_n efg_n be_v move_v with_o simple_a circular_a motion_n which_o be_v to_o be_v demonstrate_v 11_o if_o in_o a_o fluid_fw-la medium_fw-la who_o part_n be_v stir_v by_o a_o body_n move_v with_o simple_a motion_n there_o float_v another_o body_n which_o have_v its_o superficies_n either_o whole_o hard_a or_o whole_o fluid_a the_o part_n of_o this_o body_n shall_v approach_v the_o centre_n equal_o on_o all_o side_n that_o be_v to_o say_v the_o motion_n of_o the_o body_n shall_v be_v circular_a and_o concentrique_fw-la with_o the_o motion_n of_o the_o movent_fw-la but_o if_o it_o have_v one_o side_n hard_o and_o the_o other_o side_n fluid_a then_o both_o those_o motion_n shall_v not_o have_v the_o same_o centre_n nor_o shall_v the_o float_a body_n be_v move_v in_o the_o circumference_n of_o a_o perfect_a circle_n let_v a_o body_n be_v move_v in_o the_o circumference_n of_o the_o circle_n kl_n mn_v in_o the_o 2d_o figure_n who_o centre_n be_v a._n and_o let_v there_o be_v another_o body_n at_o i_o who_o superficies_n be_v either_o all_o hard_a or_o all_o fluid_a also_o let_v the_o medium_fw-la in_o which_o both_o the_o body_n be_v place_v be_v fluid_a i_o say_v the_o body_n at_o i_o will_v be_v move_v in_o the_o circle_n ib_n about_o the_o centre_n a._n for_o this_o have_v be_v demonstrate_v in_o the_o last_o article_n wherefore_o let_v the_o superficies_n of_o the_o body_n at_o i_o be_v fluid_a on_o one_o side_n and_o hard_o on_o the_o other_o and_o first_o let_v the_o fluid_a side_n be_v towards_o the_o centre_n see_v therefore_o the_o motion_n of_o the_o medium_fw-la be_v such_o as_o that_o its_o part_n do_v continual_o change_v their_o place_n as_o have_v be_v show_v in_o the_o 5_o article_n if_o this_o change_n of_o place_n be_v consider_v in_o those_o part_n of_o the_o medium_fw-la which_o be_v contiguous_a to_o the_o fluid_a superficies_n it_o must_v needs_o be_v that_o the_o small_a part_n of_o that_o superficies_n enter_v into_o the_o place_n of_o the_o small_a part_n of_o the_o medium_fw-la which_o be_v contiguous_a to_o they_o and_o the_o like_a change_n of_o place_n will_v be_v make_v with_o the_o next_o contiguous_a part_n towards_o a._n and_o if_o the_o fluid_a part_n of_o the_o body_n at_o i_o have_v any_o degree_n at_o all_o of_o tenacity_n for_o there_o be_v degree_n of_o tenacity_n as_o in_o the_o air_n and_o water_n the_o whole_a fluid_a side_n will_v be_v lift_v up_o a_o little_a but_o so_o much_o the_o less_o as_o its_o part_n have_v less_o tenacity_n whereas_o the_o hard_a part_n of_o the_o superficies_n which_o be_v contiguous_a to_o the_o fluid_a part_n have_v no_o cause_n at_o all_o of_o elevation_n that_o be_v to_o say_v no_o endeavour_n towards_o a._n second_o let_v the_o hard_a superficies_n of_o the_o body_n at_o i_o be_v towards_o a._n by_o reason_n therefore_o of_o the_o say_a change_n of_o place_n of_o the_o part_n which_o be_v contiguous_a to_o it_o the_o hard_a superficies_n must_v of_o necessity_n see_v by_o supposition_n there_o be_v no_o empty_a space_n either_o come_v near_o to_o a_o or_o else_o its_o small_a part_n must_v supply_v the_o contiguous_a place_n of_o the_o medium_fw-la which_o otherwise_o will_v be_v empty_a but_o this_o can_v be_v by_o reason_n of_o
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
all_o opinion_n concern_v the_o nature_n of_o infinite_a and_o eternal_a know_v only_o to_o himself_o shall_v as_o the_o first-fruit_n of_o wisdom_n be_v judge_v by_o those_o who_o ministry_n he_o mean_v to_o use_v in_o the_o order_n of_o religion_n i_o can_v therefore_o commend_v those_o that_o boast_v they_o have_v demonstrate_v by_o reason_n draw_v from_o natural_a thing_n that_o the_o world_n have_v a_o beginning_n they_o be_v contemn_v by_o idiot_n because_o they_o understand_v they_o not_o and_o by_o the_o learned_a because_o they_o understand_v they_o by_o both_o deserve_o for_o who_o can_v commend_v he_o that_o demonstrate_v thus_o if_o the_o world_n be_v eternal_a than_o a_o infinite_a number_n of_o day_n or_o other_o measure_n of_o time_n precede_v the_o birth_n of_o abraham_n but_o the_o birth_n of_o abraham_n precede_v the_o birth_n of_o isaac_n and_o therefore_o one_o infinite_a be_v great_a than_o another_o infinite_a or_o one_o eternal_a than_o another_o eternal_a which_o he_o say_v be_v absurd_a this_o demonstration_n be_v like_o he_o who_o from_o this_o that_o the_o number_n of_o even_a number_n be_v infinite_a will_v conclude_v that_o there_o be_v as_o many_o even_a number_n as_o there_o be_v number_n simple_o that_o be_v to_o say_v the_o even_a number_n be_v as_o many_o as_o all_o the_o even_a and_o odd_a together_o they_o which_o in_o this_o manner_n take_v away_o eternity_n from_o the_o world_n do_v they_o not_o by_o the_o same_o mean_n take_v away_o eternity_n from_o the_o creator_n of_o the_o woâ—ld_n from_o this_o absurdity_n therefore_o they_o run_v into_o another_o be_v force_v to_o call_v eternity_n nunc_fw-la stans_fw-la a_o stand_v still_o of_o the_o present_a time_n or_o a_o abide_n now_o and_o which_o be_v much_o more_o absurd_a to_o give_v to_o the_o infinite_a number_n of_o number_n the_o name_n of_o unity_n but_o why_o shall_v eternity_n be_v call_v a_o abide_n now_o rather_o than_o a_o abide_n then_o wherefore_o there_o must_v either_o be_v many_o eternity_n or_o now_o and_o then_o must_v signify_v the_o same_o with_o such_o demonstrator_n as_o these_o that_o speak_v in_o another_o language_n it_o be_v impossible_a to_o enter_v into_o disputation_n and_o the_o man_n that_o reason_n thus_o absurd_o be_v not_o idiot_n but_o which_o make_v the_o absurdity_n unpardonable_a geometrician_n and_o such_o as_o take_v upon_o they_o to_o be_v judge_n impertinent_a but_o severe_a judge_n of_o other_o man_n demonstration_n the_o reason_n be_v this_o that_o as_o soon_o as_o they_o be_v entangle_v in_o the_o word_n infinite_a and_o eternal_a of_o which_o we_o have_v in_o our_o mind_n no_o idea_n but_o that_o of_o our_o own_o insufficiency_n to_o comprehend_v they_o they_o be_v force_v either_o to_o speak_v something_o absurd_a or_o which_o they_o love_v worse_o to_o hold_v their_o peace_n for_o geometry_n have_v in_o it_o somewhat_o like_o wine_n which_o when_o new_a be_v windy_a but_o afterward_o though_o less_o pleasant_a yet_o more_o wholesome_a whatsoever_o therefore_o be_v true_a young_a geometrician_n think_v demonstrable_a but_o elder_n not_o wherefore_o i_o purposely_o pass_v over_o the_o question_n of_o infinite_a and_o eternal_a content_v myself_o with_o that_o doctrine_n concern_v the_o beginning_n and_o magnitude_n of_o the_o world_n which_o i_o have_v be_v persuade_v to_o by_o the_o holy_a scripture_n and_o fame_n of_o the_o miracle_n which_o confirm_v they_o and_o by_o the_o custom_n of_o my_o country_n and_o reverence_v due_a to_o the_o law_n and_o so_o i_o pass_v on_o to_o such_o thing_n as_o it_o be_v not_o unlawful_a to_o dispute_v of_o 2_o concern_v the_o world_n it_o be_v further_o question_v whether_o the_o part_n thereof_o be_v contiguous_a to_o one_o another_o in_o such_o manner_n as_o not_o to_o admit_v of_o the_o least_o empty_a space_n between_o and_o the_o disputation_n both_o for_o &_o against_o it_o be_v carry_v on_o with_o probability_n enough_o for_o the_o take_n away_o of_o vacuum_n i_o will_v instance_n in_o only_a one_o experiment_n a_o common_a one_o but_o i_o think_v unanswerable_a let_v ab_fw-la in_o the_o first_o fig._n represent_v a_o vessel_n such_o as_o gardiner_n use_n to_o water_v their_o garden_n withal_o who_o bottom_n b_o be_v full_a of_o little_a hole_n &_o who_o mouth_n a_o may_v be_v stop_v with_o one_o finger_n when_o there_o shall_v be_v need_n if_o now_o this_o vessel_n be_v fill_v with_o water_n the_o hole_n at_o the_o top_n a_o be_v stop_v the_o water_n will_v not_o flow_v out_o at_o any_o of_o the_o hole_n in_o the_o bottom_n b._n but_o if_o the_o finger_n be_v remove_v to_o let_v in_o the_o air_n above_o it_o will_v run_v out_o at_o they_o all_o and_o as_o soon_o as_o the_o finger_n be_v apply_v to_o it_o again_o the_o water_n will_v sudden_o &_o total_o be_v stay_v again_o from_o run_v out_o the_o cause_n whereof_o seem_v to_o be_v no_o other_o but_o this_o that_o the_o water_n can_v by_o its_o natural_a endeavour_n to_o descend_v drive_v down_o the_o air_n below_o it_o because_o there_o be_v no_o place_n for_o it_o to_o go_v into_o unless_o either_o by_o thrust_v away_o the_o next_o contiguous_a air_n it_o proceed_v by_o continual_a endeavour_n to_o the_o hole_n a_o where_o it_o may_v enter_v and_o succeed_v into_o the_o place_n of_o the_o water_n that_o flow_v out_o or_o else_o by_o resist_v the_o endeavour_n of_o the_o water_n downward_o penetrate_v the_o same_o and_o pass_v up_o through_o it_o by_o the_o first_o of_o these_o way_n while_o the_o hole_n at_o a_o remain_v stop_v there_o be_v no_o possible_a passage_n nor_o by_o the_o second_o unless_o the_o hole_n be_v so_o great_a that_o the_o water_n flow_v out_o at_o they_o can_v by_o its_o own_o weight_n force_v the_o air_n at_o the_o same_o time_n to_o ascend_v into_o the_o vessel_n by_o the_o same_o hole_n as_o we_o see_v it_o do_v in_o a_o vessel_n who_o mouth_n be_v wide_a enough_o when_o we_o turn_v sudden_o the_o bottom_n upward_o to_o pour_v out_o the_o water_n for_o then_o the_o air_n be_v force_v by_o the_o weight_n of_o the_o water_n enter_v as_o be_v evident_a by_o the_o sob_a and_o resistance_n of_o the_o water_n at_o the_o side_n or_o circumference_n of_o the_o orifice_n and_o this_o i_o take_v for_o a_o sign_n that_o all_o space_n be_v full_a for_o without_o this_o the_o natural_a motion_n of_o the_o water_n which_o be_v a_o heavy_a body_n downward_o will_v not_o be_v hinder_v 3_o on_o the_o contrary_a for_o the_o establish_n of_o vacuum_n many_o &_o specious_a argument_n and_o experiment_n have_v be_v bring_v nevertheless_o there_o seem_v to_o be_v something_o want_v in_o all_o of_o they_o to_o conclude_v it_o firm_o these_o argument_n for_o vacuum_n be_v partly_o make_v by_o the_o follower_n of_o the_o doctrine_n of_o epicurus_n who_o teach_v that_o the_o world_n consist_v of_o very_o small_a space_n not_o fill_v by_o any_o body_n and_o of_o very_o small_a body_n that_o have_v within_o they_o no_o empty_a 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all_o at_o once_o and_o together_o be_v at_o rest_n they_o will_v never_o be_v move_v again_o for_o it_o have_v be_v demonstrate_v above_o in_o the_o 9th_o chapter_n seven_o article_n that_o nothing_o can_v be_v move_v but_o by_o that_o which_o be_v contiguous_a and_o already_o move_v but_o suppose_v that_o all_o thing_n be_v at_o rest_n together_o there_o can_v be_v nothing_o contiguous_a and_o move_v and_o therefore_o no_o beginning_n of_o motion_n now_o the_o deny_v of_o the_o begin_n of_o motion_n do_v not_o take_v away_o present_a motion_n unless_o beginning_n be_v take_v away_o from_o body_n also_o for_o motion_n may_v be_v either_o coeternal_a or_o concreated_a with_o body_n nor_o do_v it_o seem_v more_o necessary_a that_o body_n be_v first_o at_o rest_n and_o afterward_o move_v then_o that_o they_o be_v
first_o move_v and_o rest_v if_o ever_o they_o rest_v at_o all_o afterward_o neither_o do_v there_o appear_v any_o cause_n why_o the_o matter_n of_o the_o world_n shall_v for_o the_o admission_n of_o motion_n be_v intermingle_v with_o empty_a space_n rather_o than_o full_a i_o say_v full_a but_o withal_o fluid_a nor_o last_o be_v there_o any_o reason_n why_o those_o hard_a atom_n may_v not_o also_o by_o the_o motion_n of_o intermingle_v fluid_a matter_n be_v congregat_v &_o bring_v together_o into_o compound_a body_n of_o such_o bigness_n as_o we_o see_v wherefore_o nothing_o can_v by_o this_o argument_n be_v conclude_v but_o that_o motion_n be_v either_o coeternal_a or_o of_o the_o same_o duration_n with_o that_o which_o be_v move_v neither_o of_o which_o conclusion_n consist_v with_o the_o doctrine_n of_o epicurus_n who_o allow_v neither_o to_o the_o world_n nor_o to_o motion_n any_o beginning_n at_o all_o the_o necessity_n therefore_o of_o vacuum_n be_v not_o hitherto_o demonstrate_v and_o the_o cause_n as_o far_o as_o i_o understand_v from_o they_o that_o have_v discourse_v with_o i_o of_o vacuum_n be_v this_o that_o while_o they_o contemplate_v the_o nature_n of_o fluid_a they_o conceive_v it_o to_o consist_v as_o it_o be_v of_o small_a grain_n of_o hard_a matter_n in_o such_o manner_n as_o meal_n be_v fluid_a make_v so_o by_o grind_v of_o the_o corn_n when_o nevertheless_o it_o be_v possible_a to_o conceive_v fluid_a to_o be_v of_o its_o own_o nature_n as_o homogeneous_a as_o either_o a_o atom_n or_o as_o vacuum_n itself_o the_o second_o of_o their_o argument_n be_v take_v from_o weight_n and_o be_v contain_v in_o these_o verse_n of_o lucretius_n corporis_fw-la officium_fw-la est_fw-la quoniam_fw-la premere_fw-la omne_fw-la deorsum_fw-la contrà _fw-la autem_fw-la natura_fw-la manet_fw-la sine_fw-la pondere_fw-la inanis_fw-la ergo_fw-la quod_fw-la magnum_fw-la est_fw-la aeque_fw-la leviusque_fw-la videtur_fw-la nimirum_fw-la plus_fw-la esse_fw-la sibi_fw-la declarat_fw-la inanis_fw-la that_o be_v to_o say_v see_v the_o office_n and_o property_n of_o body_n be_v to_o press_v all_o thing_n downward_o and_o on_o the_o contrary_a see_v the_o nature_n of_o vacuum_n be_v to_o have_v no_o weight_n at_o all_o therefore_o when_o of_o two_o body_n of_o equal_a magnitude_n one_o be_v light_a than_o the_o other_o it_o be_v manifest_a that_o the_o light_a body_n have_v in_o it_o more_o vacuum_n than_o the_o other_o to_o say_v nothing_o of_o the_o assumption_n concern_v the_o endeavour_n of_o body_n downward_o which_o be_v not_o right_o assume_v because_o the_o world_n have_v nothing_o to_o do_v with_o downward_o which_o be_v a_o mere_a fiction_n of_o we_o nor_o of_o this_o that_o if_o all_o thing_n tend_v to_o the_o same_o low_a part_n of_o the_o world_n either_o there_o will_v be_v no_o coalescence_n at_o all_o of_o body_n or_o they_o will_v all_o be_v gather_v together_o into_o the_o same_o place_n this_o only_a be_v sufficient_a to_o take_v away_o the_o force_n of_o the_o argument_n that_o air_n intermingle_v with_o those_o his_o atom_n have_v serve_v as_o well_o for_o his_o purpose_n as_o his_o intermingle_v vacuum_n the_o three_o argument_n be_v draw_v from_o this_o that_o lightning_n sound_z heatt_z and_o cold_a do_v penetrate_v all_o body_n except_o atom_n how_o solid_a soever_o they_o be_v but_o this_o reason_n except_o it_o be_v first_o demonstrate_v that_o the_o same_o thing_n can_v happen_v without_o vacuum_n by_o perpetual_a generation_n of_o motion_n be_v altogether_o invalid_a but_o that_o all_o the_o same_o thing_n may_v so_o happen_v shall_v in_o due_a place_n be_v demonstrate_v last_o the_o four_o argument_n be_v set_v down_o by_o the_o same_o lucretius_n in_o these_o verse_n duo_o de_fw-la concursu_fw-la corpora_fw-la lata_fw-la si_fw-la citò_fw-la dissiliant_fw-la nempe_fw-la aer_fw-la omne_fw-la necesse_fw-la est_fw-la inter_fw-la corpora_fw-la quod_fw-la fuerat_fw-la possidat_fw-la inane_fw-la 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small_a superficies_n of_o their_o own_o then_o if_o two_o body_n shall_v be_v join_v together_o by_o many_o or_o but_o one_o only_a small_a superficies_n of_o either_o of_o they_o than_o i_o say_v this_o argument_n of_o lucretius_n will_v be_v a_o firm_a demonstration_n that_o no_o two_o body_n make_v up_o of_o atom_n as_o he_o suppose_v can_v ever_o possible_o be_v pull_v asunder_o by_o any_o force_n whatsoever_o but_o this_o be_v repugnant_a to_o daily_a experience_n and_o thus_o much_o of_o the_o argument_n of_o lucretius_n let_v we_o now_o consider_v the_o argument_n which_o be_v draw_v from_o the_o experiment_n of_o late_a writer_n 4_o the_o first_o experiment_n be_v this_o that_o if_o a_o hollow_a vessel_n be_v thrust_v into_o water_n with_o the_o bottom_n upward_o the_o water_n will_v ascend_v into_o it_o which_o they_o say_v it_o can_v not_o do_v unless_o the_o air_n within_o be_v thrust_v together_o into_o a_o narrow_a place_n and_o that_o this_o be_v also_o impossible_a except_o there_o be_v little_a empty_a place_n in_o the_o air_n also_o that_o when_o the_o air_n be_v compress_v to_o a_o certain_a degree_n it_o can_v receive_v no_o further_o compression_n its_o small_a particle_n not_o suffer_v themselves_o to_o be_v pen_v into_o less_o room_n this_o reason_n if_o the_o air_n can_v not_o pass_v through_o the_o water_n as_o it_o ascend_v within_o the_o vessel_n may_v seem_v valid_a but_o it_o be_v sufficient_o know_v that_o air_n will_v penetrate_v water_n by_o the_o application_n of_o a_o force_n equal_a to_o the_o gravity_n of_o the_o water_n if_o therefore_o the_o force_n by_o which_o the_o vessel_n be_v thrust_v down_o be_v great_a or_o equal_a to_o the_o endeavour_n by_o which_o the_o water_n natural_o tend_v downward_o the_o air_n will_v go_v out_o that_o way_n where_o the_o resistance_n be_v make_v namely_o towards_o the_o edge_n of_o the_o vessel_n for_o by_o how_o much_o the_o deep_a be_v the_o water_n which_o be_v to_o be_v penetrate_v so_o 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cylinder_n be_v set_v upright_o we_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 near_o the_o bottom_n that_o there_o may_v be_v only_a space_n enough_o leave_v for_o the_o free_a passage_n of_o the_o water_n which_o be_v thrust_v in_o above_o let_v the_o upper_a end_n of_o this_o pipe_n have_v a_o cover_v at_o d_o with_o a_o spout_n at_o e_o by_o which_o the_o water_n when_o it_o ascend_v in_o the_o pipe_n may_v run_v out_o also_o let_v h_n c_o be_v a_o cock_n for_o the_o open_n or_o shut_v of_o the_o passage_n of_o the_o water_n between_o b_o and_o d_o as_o there_o shall_v be_v occasion_n let_v the_o cover_n d_o e_o be_v take_v off_o and_o the_o cock_n h_o c_o being_z open_v let_v a_o syringe_n fall_v of_o water_n be_v force_v in_o and_o before_o the_o syringe_n be_v take_v away_o let_v the_o cock_n be_v turn_v to_o hinder_v the_o go_v out_o of_o the_o air_n and_o in_o this_o manner_n let_v the_o injection_n of_o water_n be_v repeat_v as_o often_o as_o it_o shall_v be_v requisite_a till_o the_o water_n rise_v within_o the_o bottle_n for_o example_n to_o g_o f._n 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
of_o this_o evocation_n and_o swell_v and_o such_o as_o agree_v with_o the_o rest_n of_o the_o phaenomena_n of_o heat_n may_v be_v think_v to_o have_v give_v the_o cause_n of_o the_o heat_n of_o the_o sun_n it_o have_v be_v show_v in_o the_o 5_o article_n of_o the_o 21_o chapter_n that_o the_o fluid_fw-la medium_fw-la which_o we_o call_v the_o air_n be_v so_o move_v by_o the_o simple_a circular_a motion_n of_o the_o sun_n as_o that_o all_o its_o part_n even_o the_o least_o do_v perpetual_o change_v place_n with_o one_o another_o which_o change_n of_o place_n be_v that_o which_o there_o i_o call_v fermentation_n from_o this_o fermentation_n of_o the_o air_n i_o have_v in_o the_o 8_o article_n of_o the_o last_o chapter_n demonstrate_v that_o the_o water_n may_v be_v draw_v up_o into_o the_o cloud_n and_o i_o shall_v now_o show_v that_o the_o fluid_a part_n may_v in_o like_a manner_n by_o the_o same_o fermentation_n be_v draw_v out_o from_o the_o internal_a to_o the_o external_a part_n of_o our_o body_n for_o see_v that_o wheresoever_o the_o fluid_fw-la medium_fw-la be_v contiguous_a to_o the_o body_n of_o any_o live_a creature_n there_o the_o part_n of_o that_o medium_fw-la be_v by_o perpetual_a change_n of_o place_n separate_v from_o one_o another_o the_o contiguous_a part_n of_o the_o live_a creature_n must_v of_o necessity_n endeavour_v to_o enter_v into_o the_o space_n of_o the_o separate_a part_n for_o otherwise_o those_o part_n suppose_v there_o be_v no_o vacuum_n will_v have_v no_o place_n to_o go_v into_o and_o therefore_o that_o which_o be_v most_o fluid_a and_o separable_a in_o the_o part_n of_o the_o live_a creature_n which_o be_v contiguous_a to_o the_o medium_fw-la will_v go_v first_o out_o and_o into_o the_o place_n thereof_o will_v succeed_v such_o other_o part_n as_o can_v most_o easy_o transpire_v through_o the_o poâ—es_n of_o the_o skin_n and_o from_o hence_o it_o be_v necessary_a that_o the_o rest_n of_o the_o part_n which_o be_v not_o separate_v must_v all_o together_o be_v move_v outward_o for_o the_o keep_n of_o all_o place_n full_a but_o this_o motion_n outward_o of_o all_o part_n together_o must_v of_o necessity_n press_v those_o part_n of_o the_o ambient_fw-la aire_n which_o be_v ready_a to_o leave_v their_o place_n and_o therefore_o all_o the_o part_n of_o the_o body_n endeavour_v at_o once_o that_o way_n make_v the_o body_n swell_v wherefore_o a_o possible_a cause_n be_v give_v of_o heat_n from_o the_o sun_n which_o be_v to_o be_v do_v 4_o we_o have_v now_o see_v how_o light_n and_o heat_n be_v generate_v heat_v by_o the_o simple_a motion_n of_o the_o medium_fw-la make_v the_o part_n perpetual_o change_v place_n with_o one_o another_o and_o light_n by_o this_o that_o by_o the_o same_o simple_a motion_n action_n be_v propagate_v in_o a_o straight_a line_n but_o when_o a_o body_n have_v its_o part_n so_o move_v that_o it_o sensible_o both_o heat_n and_o shine_v at_o the_o same_o time_n than_o it_o be_v that_o we_o say_v 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upon_o by_o the_o sunbeam_n in_o the_o straight_a line_n ea_fw-la fb_fw-la and_o gc_fw-la which_o straight_o line_n may_v in_o respect_n of_o the_o great_a distance_n of_o the_o sun_n be_v take_v for_o parallel_n and_o see_v the_o medium_fw-la within_o the_o sphere_n be_v thick_a than_o the_o medium_fw-la without_o it_o those_o beam_n will_v be_v refract_v towards_o their_o perpendicular_o let_v the_o straight_a line_n ea_z and_o gc_fw-la be_v produce_v till_o they_o cut_v the_o sphere_n in_o h_n and_o i_o and_o draw_v the_o perpendicular_n ad_fw-la and_o cd_o the_o refracted_a beam_n ea_z and_o gc_fw-la will_v of_o necessity_n fall_v the_o one_o between_o ah_o and_o ad_fw-la the_o other_o between_o ci_o and_o cd_o let_v those_o refracted_a beam_n be_v ak_a and_o cl._n and_o again_o let_v the_o line_n dkm_n &_o dln_n be_v draw_v perpendicular_a to_o the_o sphere_n and_o let_v ak_a and_o cl_n be_v produce_v till_o they_o meet_v with_o the_o straight_a line_n bd_o produce_v in_o o._n see_v therefore_o the_o medium_fw-la within_o the_o sphere_n be_v thick_a than_o that_o without_o it_o the_o refracted_a line_n ak_v will_v recede_v further_o from_o the_o perpendicular_a km_n then_o quoth_fw-mi will_v recede_v from_o the_o same_o wherefore_o quoth_fw-mi will_n fall_n between_o the_o refracted_a line_n and_o the_o perpendicular_a let_v therefore_o the_o refracted_a line_n be_v kp_n cut_a foe_n in_o p_o and_o for_o the_o same_o reason_n the_o straight_a line_n lp_n will_v be_v the_o refracted_a line_n of_o the_o straight_a line_n cl._n wherefore_o see_v the_o beam_n be_v nothing_o else_o but_o the_o way_n in_o which_o the_o motion_n be_v propagate_v the_o motion_n about_o p_o will_v be_v so_o much_o more_o vehement_a than_o the_o motion_n about_o abc_n by_o how_o much_o the_o base_a of_o the_o portion_n abc_n be_v great_a than_o the_o base_a of_o a_o like_a portion_n in_o the_o sphere_n who_o centre_n be_v p_o and_o who_o magnitude_n be_v equal_a to_o that_o of_o the_o 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heat_n that_o be_v to_o say_v fire_n be_v generate_v 6_o the_o shine_a of_o glow-worm_n some_o kind_n of_o rot_a wood_n and_o of_o a_o kind_n of_o stone_n make_v at_o bolognia_n may_v have_v one_o common_a cause_n namely_o the_o expose_v of_o they_o to_o the_o hot_a sun_n we_o find_v by_o experience_n that_o the_o bolonian_a stone_n shine_v not_o unless_o it_o be_v so_o expose_v and_o after_o it_o have_v be_v expose_v it_o shine_v but_o for_o a_o little_a time_n namely_o as_o long_o as_o it_o retain_v a_o certain_a degree_n of_o heat_n and_o the_o cause_n may_v be_v that_o the_o part_n of_o which_o it_o be_v make_v may_v together_o with_o heat_n have_v simple_a motion_n imprint_v in_o they_o by_o the_o sun_n which_o if_o it_o be_v so_o it_o be_v necessary_a that_o it_o shine_v in_o the_o dark_a as_o
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 why_o glass_n be_v so_o easy_o and_o quick_o melt_v by_o the_o small_a flame_n of_o a_o candle_n blow_v which_o will_v not_o be_v melt_v without_o blow_v but_o by_o a_o very_a strong_a fire_n now_o if_o from_o the_o same_o matter_n there_o be_v a_o part_n break_v off_o namely_o such_o a_o part_n as_o consist_v of_o many_o of_o the_o small_a particle_n of_o this_o be_v make_v a_o spark_n for_o from_o the_o break_n off_o it_o have_v a_o violent_a turn_n round_o and_o from_o hence_o it_o shine_v but_o though_o from_o this_o matter_n there_o fly_v neither_o flame_n nor_o spark_n yet_o some_o of_o the_o small_a part_n of_o it_o may_v be_v carry_v out_o as_o far_o as_o to_o the_o superficies_n and_o remain_v there_o as_o ash_n the_o part_n whereof_o be_v so_o extreme_o small_a that_o it_o can_v any_o long_o be_v doubt_v how_o far_o nature_n may_v proceed_v in_o divide_v last_o though_o by_o the_o application_n of_o fire_n to_o this_o matter_n there_o fly_v little_a or_o nothing_o from_o it_o 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
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 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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 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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
that_o be_v strike_v be_v not_o only_o sufficient_o hard_a but_o have_v also_o the_o particle_n of_o which_o it_o consist_v like_a to_o one_o another_o both_o in_o hardness_n and_o figure_n such_o as_o be_v the_o particle_n of_o glass_n and_o metal_n which_o be_v first_o melt_v do_v afterward_o settle_v and_o harden_v the_o sound_v it_o yield_v will_v because_o the_o motion_n of_o its_o part_n and_o their_o reciprocation_n be_v like_a and_o uniform_a be_v uniform_a and_o pleasant_a and_o be_v more_o or_o less_o last_a according_a as_o the_o body_n strike_v have_v gteat_a or_o less_o magnitude_n the_o possible_a cause_n therefore_o of_o sound_n uniform_a and_o harsh_a and_o of_o their_o long_a or_o short_a duration_n may_v be_v one_o and_o the_o same_o likeness_n and_o unlikeness_n of_o the_o internal_a part_n of_o the_o sound_a body_n in_o respect_n both_o of_o their_o figure_n and_o hardness_n beside_o if_o two_o plain_a body_n of_o the_o same_o matter_n and_o of_o equal_a thickness_n 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nor_o favourable_a wind_n increase_v the_o light_n unless_o it_o be_v so_o strong_a as_o to_o remove_v the_o object_n further_o off_o or_o bring_v it_o near_o to_o the_o eye_n for_o the_o wind_n that_o be_v to_o say_v the_o air_n move_v do_v not_o by_o its_o interposition_n between_o the_o object_n and_o the_o eye_n work_v otherwise_o then_o it_o will_v do_v if_o it_o be_v still_o and_o calm_a for_o where_o the_o pressure_n be_v perpetual_a one_o part_n of_o the_o air_n be_v no_o soon_o carry_v away_o but_o another_o by_o succeed_v it_o receive_v the_o same_o impression_n which_o the_o part_n carry_v away_o have_v receive_v before_o but_o in_o the_o generation_n of_o sound_n the_o first_o collision_n or_o break_v asunder_o beat_v away_o &_o drive_v out_o of_o its_o place_n the_o near_a part_n of_o the_o air_n and_o that_o to_o a_o considerable_a distance_n and_o with_o considerable_a velocity_n and_o as_o the_o circle_n grow_v by_o their_o remoteness_n wide_o and_o wide_o so_o the_o air_n be_v more_o &_o more_o dissipate_v have_v also_o its_o motion_n more_o &_o more_o weaken_a whensoever_o therefore_o the_o air_n be_v so_o strike_v as_o to_o cause_n sound_v if_o the_o wind_n fall_v upon_o it_o it_o will_v move_v it_o all_o near_o to_o the_o ear_n if_o it_o blow_v that_o way_n and_o further_o from_o it_o if_o it_o blow_v the_o contrary_a way_n so_o that_o according_a as_o it_o blow_v from_o or_o towards_o the_o object_n so_o the_o sound_n which_o be_v hear_v will_v seem_v to_o come_v from_o a_o near_o or_o remote_a place_n and_o the_o action_n by_o reason_n of_o the_o unequal_a distance_n be_v strengthen_v or_o debilitate_a from_o hence_o may_v be_v understand_v the_o reason_n why_o the_o voice_n of_o such_o as_o be_v say_v to_o speak_v in_o their_o belly_n though_o it_o be_v utter_v near_o hand_n be_v nevertheless_o hear_v by_o those_o that_o suspect_v nothing_o as_o if_o it_o be_v a_o great_a way_n off_o for_o have_v no_o former_a thought_n of_o any_o determine_a place_n from_o which_o the_o voice_n shall_v proceed_v and_o judge_v according_a to_o the_o greatesse_n if_o it_o be_v weak_a they_o think_v it_o a_o great_a way_n off_o if_o strong_a near_a these_o ventriloqui_n therefore_o by_o form_v their_o voice_n not_o as_o other_o by_o the_o emission_n of_o their_o breath_n but_o by_o draw_v it_o inward_o do_v make_v the_o same_o appear_v small_a and_o weak_a which_o weakness_n of_o the_o voice_n deceive_v those_o that_o neither_o suspect_n the_o artifice_n nor_o observe_v the_o endeavour_n which_o they_o use_v in_o speak_v and_o so_o instead_o of_o think_v it_o weak_a they_o think_v it_o far_o off_o 10_o as_o for_o the_o medium_fw-la which_o convey_v sound_a it_o be_v not_o air_n only_o for_o water_n or_o any_o other_o body_n how_o hard_o soever_o may_v be_v that_o medium_fw-la for_o the_o motion_n may_v be_v propagate_v perpetual_o in_o any_o hard_a continuous_a body_n but_o by_o reason_n of_o the_o difficulty_n with_o which_o the_o part_n of_o hard_a body_n be_v move_v the_o motion_n in_o go_v out_o of_o hard_a matter_n make_v but_o a_o weak_a impression_n upon_o the_o air_n nevertheless_o if_o one_o end_n of_o a_o very_a long_a and_o hard_a beam_n be_v strike_v &_o the_o ear_n be_v apply_v at_o the_o same_o time_n to_o the_o other_o end_n so_o that_o when_o the_o action_n go_v out_o of_o the_o beam_n the_o air_n which_o it_o strike_v may_v immediate_o be_v receive_v by_o the_o ear_n and_o be_v carry_v to_o the_o tympanum_fw-la the_o sound_n will_v be_v considerable_o strong_a in_o like_a manner_n if_o in_o the_o night_n when_o all_o other_o noise_n which_o may_v hinder_v sound_a cease_v a_o man_n lay_v his_o ear_n to_o the_o ground_n he_o will_v hear_v the_o sound_n of_o the_o step_n of_o passenger_n though_o at_o a_o great_a distance_n because_o the_o motion_n which_o by_o their_o tread_v they_o communicate_v to_o the_o earth_n be_v propagate_v to_o the_o ear_n by_o the_o uppermost_a part_n of_o the_o earth_n which_o receive_v it_o from_o their_o foot_n 11_o i_o have_v show_v above_o that_o the_o difference_n between_o grave_a and_o acute_a sound_n consist_v in_o this_o that_o by_o how_o much_o the_o short_a the_o time_n be_v in_o which_o the_o reciprocation_n of_o the_o part_n of_o a_o body_n strike_v be_v make_v by_o so_o much_o the_o more_o acute_a will_v be_v the_o sound_n now_o by_o how_o much_o a_o body_n of_o the_o same_o bigness_n be_v either_o more_o heavy_a or_o less_o stretch_v by_o so_o much_o the_o long_o will_v the_o reciprocation_n last_o and_o therefore_o heavy_a and_o less_o stretch_a body_n if_o they_o be_v like_a in_o all_o other_o respect_n will_v yield_v a_o grave_a sound_n than_o such_o as_o be_v light_a and_o more_o stretch_v 12_o for_o the_o find_n out_o
of_o the_o cause_n of_o smell_v i_o shall_v make_v use_n of_o the_o evidence_n of_o these_o follow_a phaenomena_n first_o that_o smell_a be_v hinder_v by_o cold_a and_o help_v by_o heat_n second_o that_o when_o the_o wind_n blow_v from_o the_o object_n the_o smell_n be_v the_o strong_a and_o contrary_o when_o it_o blow_v from_o the_o sentient_a towards_o the_o object_n the_o weak_a both_o which_o phaenomena_n be_v by_o experience_n manifest_o find_v to_o be_v true_a in_o dog_n which_o follow_v the_o tract_n of_o beast_n by_o the_o sent._n three_o that_o such_o body_n as_o be_v less_o pervious_a to_o the_o fluid_fw-la medium_fw-la yield_v less_o smell_n than_o such_o as_o be_v more_o pervious_a as_o may_v be_v see_v in_o stone_n and_o metal_n which_o compare_v with_o plant_n and_o live_a creature_n and_o their_o part_n fruit_n and_o excretion_n have_v very_o little_a or_o no_o smell_n at_o all_o four_o that_o such_o body_n as_o be_v of_o their_o own_o nature_n odorous_a become_v yet_o 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aethereal_a substance_n be_v the_o same_o in_o all_o odorous_a body_n they_o will_v always_o affect_v the_o organ_n in_o the_o same_o manner_n and_o consequent_o the_o odour_n of_o all_o thing_n will_v be_v like_a it_o remain_v therefore_o that_o the_o cause_n of_o smell_a must_v consist_v in_o the_o simple_a motion_n of_o the_o part_n of_o odorous_a body_n without_o any_o efflux_n or_o diminution_n of_o their_o whole_a substance_n and_o by_o this_o motion_n there_o be_v propagate_v to_o the_o organ_n by_o the_o intermediate_v air_n the_o like_a motion_n but_o not_o strong_a enough_o to_o excite_v sense_n of_o itself_o without_o the_o attraction_n of_o air_n by_o respiration_n and_o this_o be_v a_o possible_a cause_n of_o smell_a 14_o the_o cause_n why_o smell_a be_v hinder_v by_o cold_a and_o help_v by_o heat_n may_v be_v this_o that_o heat_v as_o have_v be_v show_v in_o the_o 21_o chapter_n generate_v simple_a motion_n and_o therefore_o also_o wheresoever_o it_o be_v already_o there_o it_o will_v increase_v it_o and_o the_o cause_n of_o smell_a being_n increase_v the_o smell_n itself_o will_v also_o be_v increase_v as_o for_o the_o cause_n why_o the_o wind_n blow_v from_o the_o object_n make_v the_o smell_n the_o strong_a it_o be_v all_o one_o with_o that_o for_o which_o the_o attraction_n of_o air_n in_o respiration_n do_v the_o same_o for_o he_o that_o draw_v in_o the_o air_n next_o to_o he_o draws_z with_o it_o by_o succession_n that_o air_n in_o which_o be_v the_o object_n now_o this_o motion_n of_o the_o air_n be_v wind_n and_o when_o another_o wind_n blow_v from_o the_o object_n will_v be_v increase_v by_o it_o 15_o that_o body_n which_o contain_v the_o least_o quantity_n of_o air_n as_o stones_z and_o metal_n yield_v less_o smell_n than_o plant_n and_o live_a creature_n the_o cause_n may_v be_v that_o the_o motion_n which_o cause_v smell_a be_v a_o motion_n of_o the_o fluid_a part_n only_o which_o part_n if_o they_o have_v any_o motion_n from_o the_o hard_a part_n in_o which_o they_o be_v contain_v they_o communicate_v the_o same_o to_o the_o open_a air_n by_o which_o it_o be_v propagate_v to_o the_o organ_n where_o therefore_o there_o be_v no_o fluid_a part_n as_o in_o metal_n or_o where_o the_o fluid_a part_n receive_v no_o motion_n from_o the_o hard_a part_n as_o in_o stone_n which_o be_v make_v hard_o by_o accretion_n there_o can_v be_v no_o smell_n and_o therefore_o also_o the_o water_n who_o part_n have_v little_a or_o no_o motion_n yield_v no_o smell_n but_o if_o the_o same_o water_n by_o seed_n and_o the_o heat_n of_o the_o sun_n be_v together_o with_o particle_n of_o earth_n raise_v into_o a_o plant_n and_o be_v afterward_o press_v out_o again_o it_o will_v be_v odorous_a as_o wine_n from_o the_o vine_n and_o as_o water_n pass_v through_o plant_n be_v by_o the_o motion_n
of_o the_o part_n of_o those_o plant_n make_v a_o odorous_a liquor_n so_o also_o of_o air_n pass_v through_o the_o same_o plant_n while_o they_o be_v grow_v be_v make_v odorous_a air_n and_o thus_o also_o it_o be_v with_o the_o juice_n and_o spirit_n which_o be_v breed_v in_o live_v creature_n 16_o that_o odorous_a body_n may_v be_v make_v more_o odorous_a by_o contrition_n proceed_v from_o this_o that_o be_v break_v into_o many_o part_n which_o be_v all_o odorous_a the_o air_n which_o by_o respiration_n be_v draw_v from_o the_o object_n towards_o the_o organ_n do_v in_o its_o passage_n touch_v upon_o all_o those_o part_n and_o receive_v their_o motion_n now_o the_o air_n touch_v the_o superficies_n only_o and_o a_o body_n have_v less_o superficies_n while_o it_o be_v whole_a than_o all_o its_o part_n together_o have_v after_o it_o be_v reduce_v to_o powder_n it_o follow_v that_o the_o same_o odorous_a body_n yield_v less_o smell_n while_o it_o be_v whole_a than_o it_o will_v do_v after_o it_o be_v break_v into_o small_a part_n and_o thus_o much_o of_o smell_v 17_o the_o taste_n follow_v who_o generation_n have_v this_o difference_n from_o that_o of_o the_o sight_n hear_v and_o smell_a that_o by_o these_o we_o have_v sense_n of_o remote_a object_n whereas_o we_o taste_v nothing_o but_o what_o be_v contiguous_a and_o do_v immediate_o touch_v either_o the_o tongue_n or_o palate_n or_o both_o from_o whence_o it_o be_v evident_a that_o the_o cuticle_n of_o the_o tongue_n and_o palate_n and_o the_o nerve_n insert_v into_o they_o be_v the_o first_o organ_n of_o taste_n and_o because_o from_o the_o concussion_n of_o the_o part_n of_o these_o there_o follow_v necessary_o a_o concussion_n of_o the_o pia_fw-la mater_fw-la that_o the_o action_n communicate_v to_o these_o be_v propagate_v to_o the_o brain_n and_o from_o thence_o to_o the_o far_a organ_n namely_o the_o heart_n in_o who_o reaction_n consist_v the_o nature_n of_o sense_n now_o that_o savour_v as_o well_o as_o odour_n do_v not_o only_o move_v the_o brain_n but_o the_o stomach_n also_o as_o be_v manifest_a by_o the_o loathe_n that_o be_v cause_v by_o they_o both_o they_o that_o consider_v the_o organ_n of_o both_o these_o sense_n will_v not_o wonder_v at_o all_o see_v the_o tongue_n the_o palate_n &_o the_o nostril_n have_v one_o and_o the_o same_o continue_a cuticle_n derive_v from_o the_o dura_n mater_n and_o that_o effluvium_n have_v nothing_o to_o do_v in_o the_o sense_n of_o taste_v be_v manifest_a from_o this_o that_o there_o be_v no_o taste_n where_o the_o organ_n and_o the_o object_n be_v not_o contiguous_a by_o what_o variety_n of_o motion_n the_o different_a kind_n of_o taste_n which_o be_v innumerable_a may_v be_v distinguish_v i_o know_v not_o i_o may_v with_o other_o derive_v they_o from_o the_o divers_a figure_n of_o those_o atom_n of_o which_o whatsoever_o may_v be_v taste_v consist_v or_o from_o the_o diverse_a motion_n which_o i_o may_v by_o way_n of_o supposition_n attribute_v to_o those_o atom_n conjecture_v not_o without_o some_o likelihood_n of_o truth_n that_o such_o thing_n as_o taste_v sweet_a have_v their_o particle_n move_v with_o slow_a circular_a motion_n and_o their_o figure_n spherical_a which_o make_v they_o smooth_a and_o please_a to_o the_o organ_n that_o bitter_a thing_n have_v circular_a motion_n but_o vehement_a and_o their_o figure_n full_a of_o angle_n by_o which_o they_o trouble_v the_o organ_n and_o that_o sour_a thing_n have_v straight_o and_o reciprocal_a motion_n and_o their_o figure_n long_o and_o small_a so_o that_o they_o cut_v and_o wound_v the_o organ_n and_o in_o like_a manner_n i_o may_v assign_v for_o the_o cause_n of_o other_o taste_v such_o several_a motion_n and_o figure_n of_o atom_n as_o might_n in_o probability_n seem_v to_o be_v the_o true_a cause_n but_o this_o will_v be_v to_o revolt_v from_o philosophy_n to_o divination_n 18_o by_o the_o touch_n we_o feel_v what_o body_n be_v cold_a or_o hot_a though_o they_o be_v distant_a from_o we_o other_o as_o hard_a soft_a rough_a and_o smooth_a we_o can_v feel_v unless_o they_o be_v contiguous_a the_o organ_n of_o touch_n be_v every_o one_o of_o those_o membrane_n which_o be_v continue_v from_o the_o pia_fw-la mater_fw-la be_v so_o diffuse_v throughout_o the_o whole_a body_n as_o that_o no_o part_n of_o it_o can_v be_v press_v but_o the_o pia_n mater_n be_v press_v together_o with_o it_o whatsoever_o therefore_o press_v it_o be_v feel_v as_o hard_a or_o soft_a that_o be_v to_o say_v as_o more_o or_o less_o hard._n and_o as_o for_o the_o sense_n of_o rough_a it_o be_v nothing_o else_o but_o innumerable_a perception_n of_o hard_a and_o hard_o succeed_v one_o another_o by_o short_a interval_n both_o of_o time_n and_o place_n for_o we_o take_v notice_n of_o rough_a and_o smooth_a as_o also_o of_o magnitude_n and_o figure_n not_o only_o by_o the_o touch_n but_o also_o by_o memory_n for_o though_o some_o thing_n be_v touch_v in_o one_o point_n yet_o rough_a and_o smooth_a like_a quantity_n and_o figure_n be_v not_o perceive_v but_o by_o the_o flux_n of_o a_o point_n that_o be_v to_o say_v we_o have_v no_o sense_n of_o they_o without_o time_n and_o we_o can_v have_v no_o sense_n of_o time_n without_o memory_n chap._n xxx_o of_o gravity_n 1_o a_o thick_a body_n do_v not_o contain_v more_o matter_n unless_o also_o more_o place_n than_o a_o thin_a 2_o that_o the_o descent_n of_o heavy_a body_n proceed_v not_o from_o their_o own_o appetite_n but_o from_o some_o power_n of_o the_o earth_n 3_o the_o difference_n of_o gravity_n proceed_v from_o the_o difference_n of_o the_o impetus_fw-la with_o which_o the_o element_n whereof_o heavy_a body_n be_v make_v do_v fall_v upon_o the_o earth_n 4_o the_o cause_n of_o the_o descent_n of_o heavy_a body_n 5_o in_o what_o proportion_n the_o descent_n of_o heavy_a body_n be_v accelerate_a 6_o why_o those_o that_o dive_v do_v not_o when_o they_o be_v under_o water_n feel_v the_o weight_n of_o the_o water_n above_o they_o 7_o the_o weight_n of_o a_o body_n that_o float_v 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 space_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 8_o if_o a_o body_n be_v light_a than_o water_n then_o how_o big_a soever_o that_o body_n be_v it_o will_v float_v upon_o any_o quantity_n of_o water_n how_o little_a soever_o 9_o how_o water_n may_v be_v lift_v up_o and_o force_v out_o of_o a_o vessel_n by_o air._n 10_o why_o a_o bladder_n be_v heavy_a when_o blow_v full_a of_o air_n then_o when_o it_o be_v empty_a 11_o the_o cause_n of_o the_o ejection_n upward_o of_o heavy_a body_n from_o a_o windgun_n 12_o the_o cause_n of_o the_o ascent_n of_o water_n in_o a_o weatherglass_n 13_o the_o cause_n of_o motion_n upward_o in_o live_v creature_n 14_o that_o there_o be_v in_o nature_n a_o kind_n of_o body_n heavy_a than_o air_n which_o nevertheless_o be_v not_o by_o sense_n distinguishable_a from_o it_o 15_o of_o the_o cause_n of_o magnetical_a virtue_n 1_o in_o the_o 21_o chapter_n i_o have_v define_v thick_a and_o thin_a as_o that_o place_n require_v so_o as_o that_o by_o thick_a be_v signify_v a_o more_o resist_a body_n and_o by_o thin_a a_o body_n less_o resist_v follow_v the_o custom_n of_o those_o that_o have_v before_o i_o discourse_v of_o refraction_n now_o if_o we_o consider_v the_o true_a and_o vulgar_a signification_n of_o those_o word_n we_o shall_v find_v they_o to_o be_v name_n collective_a that_o be_v to_o say_v name_n of_o multitude_n as_o thick_a to_o be_v that_o which_o take_v up_o more_o part_n of_o a_o space_n give_v &_o thin_a that_o which_o contain_v few_o part_n of_o the_o same_o magnitude_n in_o the_o same_o space_n or_o in_o a_o space_n equal_a to_o it_o thick_o therefore_o be_v the_o same_o with_o frequent_a as_o a_o thick_a troop_n and_o thin_a the_o same_o with_o unfrequent_a as_o a_o thin_a rank_n thin_a of_o house_n not_o that_o there_o be_v more_o matter_n in_o one_o place_n then_o in_o another_o equal_a place_n but_o a_o great_a quantity_n of_o some_o name_v body_n for_o there_o be_v not_o less_o matter_n or_o body_n indefinite_o take_v in_o a_o desert_n then_o there_o be_v in_o a_o city_n but_o few_o house_n or_o few_o men._n nor_o be_v there_o in_o a_o thick_a rank_n a_o great_a quantity_n of_o body_n but_o a_o great_a number_n of_o soldier_n then_o in_o a_o thin_a wherefore_o the_o multitude_n &_o paucity_n of_o the_o part_n contain_v within_o the_o same_o space_n do_v constitute_v density_n and_o rarity_n whether_o those_o part_n be_v separate_v by_o vacuum_n or_o by_o air_n but_o the_o consideration_n of_o this_o be_v not_o of_o any_o great_a moment_n in_o philosophy_n and_o therefore_o i_o let_v
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