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exhibit_v two_o distinct_a and_o differ_a colour_n but_o in_o that_o place_n where_o they_o be_v unite_v and_o constitute_v one_o double_a plate_n as_o i_o may_v call_v it_o they_o appear_v transparent_a and_o colourless_a nor_o second_o may_v the_o plate_n be_v thin_a than_o such_o a_o determinate_a cize_n for_o we_o always_o find_v that_o the_o very_a outmost_a rim_z of_o these_o flaw_n be_v terminate_v in_o a_o white_a and_o colourless_a ring_n further_o in_o this_o production_n of_o colour_n there_o be_v no_o need_n of_o a_o determinate_a light_n of_o such_o a_o bigness_n and_o no_o more_o nor_o of_o a_o determinate_a position_n of_o that_o light_n that_o it_o shall_v be_v on_o this_o side_n and_o not_o on_o that_o side_n nor_o of_o a_o terminate_a shadow_n as_o in_o the_o prism_n and_o rainbow_n or_o water-ball_n for_o we_o find_v that_o the_o light_n in_o the_o open_a air_n either_o in_o or_o out_o of_o the_o sunbeam_n and_o within_o a_o room_n either_o from_o one_o or_o many_o window_n produce_v much_o the_o same_o effect_n only_o where_o the_o light_n be_v bright_a there_o the_o colour_n be_v most_o vivid_v so_o do_v the_o light_n of_o a_o candle_n collect_v by_o a_o glass-ball_n and_o further_o it_o be_v all_o one_o whatever_o side_n of_o the_o colour_a ring_n be_v towards_o the_o light_n for_o the_o whole_a ring_n keep_v its_o proper_a colour_n from_o the_o middle_a outward_n in_o the_o same_o order_n as_o i_o before_o relate_v without_o vary_v at_o all_o upon_o change_v the_o position_n of_o the_o light_n but_o above_o all_o it_o be_v most_o observable_a that_o here_o be_v all_o kind_n of_o colour_n generate_v in_o a_o pellucid_a body_n where_o there_o be_v proper_o no_o such_o refraction_n as_o des_n cartes_n suppose_v his_o globule_n to_o acquire_v a_o verticity_n by_o for_o in_o the_o plain_a and_o even_a plate_n it_o be_v manifest_a that_o the_o second_o refraction_n according_a to_o des_n cartes_n his_o principle_n in_o the_o five_o section_n of_o the_o eight_o chapter_n of_o his_o meteor_n do_v regulate_v and_o restore_v the_o suppose_a turbinated_a globule_n unto_o their_o former_a uniform_a motion_n this_o experiment_n therefore_o will_v prove_v such_o a_o one_o as_o our_o thrice_o excellent_a verulam_n call_v experimentum_fw-la crucis_fw-la serve_v as_o a_o guide_n or_o landmark_n by_o which_o to_o direct_v our_o course_n in_o the_o search_n after_o the_o true_a cause_n of_o colour_n afford_v we_o this_o particular_a negative_a information_n that_o for_o the_o production_n of_o colour_n there_o be_v not_o necessary_a either_o a_o great_a refraction_n as_o in_o the_o prism_n nor_o second_o a_o determination_n of_o light_n and_o shadow_n such_o as_o be_v both_o in_o the_o prism_n and_o glass-ball_n now_o that_o we_o may_v see_v likewise_o what_o affirmative_a and_o positive_a instruction_n it_o yield_v it_o will_v be_v necessary_a to_o examine_v it_o a_o little_a more_o particular_o and_o strict_o which_o that_o we_o may_v the_o better_a do_v it_o will_v be_v requisite_a to_o premise_v somewhat_o in_o general_a concern_v the_o nature_n of_o light_n and_o refraction_n and_o first_o for_o light_n it_o seem_v '_o very_a manifest_a that_o there_o be_v no_o luminous_a body_n but_o have_v the_o part_n of_o it_o in_o motion_n more_o or_o less_o first_o that_o all_o kind_n of_o fiery_a burn_a body_n have_v their_o part_n in_o motion_n i_o think_v will_v be_v very_o easy_o grant_v i_o that_o the_o spark_n strike_v from_o a_o flint_n and_o steel_n be_v in_o a_o rapid_a agitation_n i_o have_v elsewhere_o make_v probable_a and_o that_o the_o part_n of_o rot_a wood_n rot_a fish_n and_o the_o like_a be_v also_o in_o motion_n i_o think_v will_v as_o easy_o be_v concede_v by_o those_o who_o consider_v that_o those_o part_n never_o begin_v to_o shine_v till_o the_o body_n be_v in_o a_o state_n of_o putrefaction_n and_o that_o be_v now_o general_o grant_v by_o all_o to_o be_v cause_v by_o the_o motion_n of_o the_o part_n of_o putrify_a body_n that_o the_o bononian_n stone_n shine_v no_o long_o than_o it_o be_v either_o warm_v by_o the_o sunbeam_n or_o by_o the_o flame_n of_o a_o fire_n or_o of_o a_o candle_n be_v the_o general_a report_n of_o those_o that_o write_v of_o it_o and_o of_o other_o that_o have_v see_v it_o and_o that_o heat_n argue_v a_o motion_n of_o the_o internal_a part_n be_v as_o i_o say_v before_o general_o grant_v but_o there_o be_v one_o instance_n more_o which_o be_v first_o show_v to_o the_o royal_a society_n by_o mr._n clayton_n a_o worthy_a member_n thereof_o which_o do_v make_v this_o assertion_n more_o evident_a than_o all_o the_o rest_n and_o that_o be_v that_o a_o diamond_n be_v rub_v strike_v or_o beat_v in_o the_o dark_a shine_v for_o a_o pretty_a while_n after_o so_o long_o as_o that_o motion_n which_o be_v impart_v by_o any_o of_o those_o agent_n remain_v in_o the_o same_o manner_n as_o a_o glass_n rub_v strike_v or_o by_o a_o mean_n which_o i_o shall_v elsewhere_o mention_v heâ—â—ed_v yield_v a_o sound_n which_o last_v as_o long_o as_o the_o vibrate_n motion_n of_o that_o sonorous_a body_n several_a experiment_n make_v on_o which_o stone_n be_v since_o publish_v in_o a_o discourse_n of_o colour_n by_o the_o true_o honourable_a mr._n boyle_n what_o may_v be_v say_v of_o those_o ignes_fw-la fatus_fw-la that_o appear_v in_o the_o night_n i_o can_v so_o well_o affirm_v have_v never_o have_v the_o opportunity_n to_o examine_v they_o myself_o nor_o to_o be_v inform_v by_o any_o other_o that_o have_v observe_v they_o and_o the_o relation_n of_o they_o in_o author_n be_v so_o imperfect_a that_o nothing_o can_v be_v build_v on_o they_o but_o i_o hope_v i_o shall_v be_v able_a in_o another_o place_n to_o make_v it_o at_o least_o very_a probable_a that_o there_o be_v even_o in_o those_o also_o a_o motion_n which_o cause_v this_o effect_n that_o the_o shine_a of_o sea-water_n proceed_v from_o the_o same_o cause_n may_v be_v argue_v from_o this_o that_o it_o shine_v not_o till_o either_o it_o be_v beat_v against_o a_o rock_n or_o be_v some_o other_o way_n break_v or_o agitate_a by_o storm_n or_o oar_n or_o other_o pereuss_a body_n and_o that_o the_o animal_n energye_n or_o spirituous_a agile_a part_n be_v very_o active_a in_o cat_n eye_n when_o they_o shine_v seem_v evident_a enough_o because_o their_o eye_n never_o shine_v but_o when_o they_o look_v very_o intense_o either_o to_o find_v their_o prey_n or_o be_v hunt_v in_o a_o dark_a room_n when_o they_o seek_v after_o their_o adversary_n or_o to_o find_v a_o way_n to_o escape_v and_o the_o like_a may_v be_v say_v of_o the_o shine_a belly_n of_o glowworm_n since_o it_o be_v evident_a they_o can_v at_o pleasure_n either_o increase_v or_o extinguish_v that_o radiation_n it_o will_v be_v somewhat_o too_o long_o a_o work_n for_o
a_o kind_n of_o artificial_a silk_n out_o of_o some_o glutinous_a substance_n that_o may_v equalise_v natural_a silk_n obseru._n 5._o of_o water_a silk_n the_o great_a unaccurateness_n of_o artificial_a work_n a_o description_n of_o a_o piece_n of_o water_a silk_n a_o explication_n of_o the_o cause_n of_o the_o phaenomena_n the_o way_n by_o which_o that_o operation_n be_v perform_v some_o other_o phaenomena_n mention_v depend_v on_o the_o same_o cause_n obseru._n 6._o of_o glass-cane_n the_o exceed_a smallness_n of_o some_o of_o these_o body_n by_o what_o mean_v the_o hollowness_n of_o these_o small_a pipe_n be_v discover_v several_a phaenomena_n of_o it_o mention_v a_o attempt_n to_o explicate_v they_o from_o the_o congruity_n and_o incongruity_n of_o body_n what_o those_o propriety_n be_v a_o hypothetical_a explication_n of_o fluidity_n of_o the_o fluidity_n of_o the_o air_n and_o several_a other_o phaenomena_n of_o it_o of_o congruity_n &_o incongruity_n illustrate_v with_o several_a experiment_n what_o effect_n may_v be_v ascribe_v to_o these_o property_n a_o explication_n of_o the_o roundness_n of_o the_o surface_n of_o fluid_a body_n how_o the_o ingress_n of_o fluid_a body_n into_o a_o small_a hole_n of_o a_o heterogeneous_a body_n be_v hinder_v by_o incongruity_n a_o multitude_n of_o phaenomena_n explicable_a hereby_o several_a query_n propound_v 1._o concern_v the_o propagation_n of_o light_n through_o differ_v medium_n 2._o concern_v gravity_n 3._o concern_v the_o roundness_n of_o the_o sun_n moon_n and_o planet_n 4._o concern_v the_o roundness_n of_o fruit_n stone_n and_o divers_a artificial_a body_n his_o highness_n prince_n rupert_n way_n of_o make_v shoot_v of_o the_o roundness_n of_o hail_n of_o the_o grain_n of_o kettering_n stone_n and_o of_o the_o spark_n of_o fire_n 5._o concern_v springiness_n and_o tenacity_n 6._o concern_v the_o original_n of_o fountain_n several_a history_n and_o experiment_n relate_v thereto_o 7._o concern_v the_o dissolution_n of_o body_n in_o liquor_n 8._o concern_v the_o universality_n of_o this_o principle_n what_o method_n be_v take_v in_o make_v and_o apply_v experiment_n the_o explication_n of_o filtration_n and_o several_a other_o phaenomena_n such_o as_o the_o motion_n of_o body_n on_o the_o surface_n of_o liquor_n several_a experiment_n mention_v to_o this_o purpose_n of_o the_o height_n to_o which_o the_o water_n may_v rise_v in_o these_o pipe_n and_o a_o conjecture_n about_o the_o juice_n of_o vegetable_n &_o the_o use_n of_o their_o pore_n a_o further_a explication_n of_o congruity_n and_o a_o attempt_n of_o solve_v the_o phaenomena_n of_o the_o strange_a experiment_n of_o the_o suspension_n of_o the_o mercury_n at_o a_o much_o great_a height_n than_o thirty_o inch_n the_o efficacy_n of_o immediate_a contact_n and_o the_o reason_n of_o it_o obseru._n 7._o of_o glass_n drop_n several_a experiment_n make_v with_o these_o small_a body_n the_o manner_n of_o the_o break_n and_o flaw_v of_o they_o explicate_v by_o figure_n what_o other_o body_n will_v be_v flaw_v much_o in_o the_o same_o manner_n some_o other_o trial_n and_o a_o description_n of_o the_o drop_v themselves_o some_o conjecture_n at_o the_o cause_n of_o the_o phaenomena_n endeavour_v to_o be_v make_v probable_a by_o several_a argument_n and_o experiment_n a_o experiment_n of_o the_o expansion_n of_o water_n by_o heat_n and_o shrink_v by_o cold_a the_o like_a propriety_n suppose_v in_o glassdrop_v and_o what_o effect_n proceed_v from_o they_o the_o seven_o proposition_n on_o which_o the_o conjecture_n be_v ground_v experiment_n to_o show_v that_o body_n expand_v by_o heat_n the_o manner_n of_o make_v thermometer_n and_o the_o instrument_n for_o graduate_v they_o the_o manner_n of_o graduate_v they_o and_o their_o use_n other_o experiment_n to_o prove_v the_o expansion_n of_o body_n by_o heat_n four_o experimental_a argument_n to_o prove_v the_o expansion_n of_o glass_n by_o heat_n further_o prove_v by_o the_o experiment_n of_o boil_a alabaster_n which_o be_v explicate_v a_o explication_n of_o the_o contract_n of_o heat_a glass_n upon_o cool_v a_o explication_n how_o the_o part_n of_o the_o glass_n become_v bend_v by_o sudden_a cold_a and_o how_o keep_v from_o extricate_a themselves_o by_o the_o contignation_n of_o the_o glass_n drop_n which_o be_v further_o explicate_v by_o another_o experiment_n make_v with_o a_o hollow_a glass_n ball_n the_o reason_n of_o the_o fly_v asunder_o of_o the_o part_n further_o explicate_v that_o it_o be_v probable_a these_o body_n may_v have_v many_o flaw_n though_o not_o visible_a and_o why_o how_o a_o gradual_a heat_n and_o cool_a do_v put_v the_o part_n of_o glass_n and_o other_o harden_a body_n into_o a_o loose_a texture_n obseru._n 8._o of_o fiery_a spark_n the_o occasion_n and_o manner_n of_o make_v this_o experiment_n divers_a observation_n set_v down_o in_o order_n to_o the_o find_v out_o the_o reason_n some_o conjecture_n concern_v it_o which_o be_v endeavour_v to_o be_v explicate_v and_o confirm_v by_o several_a experiment_n and_o reason_n the_o hypothesis_n a_o little_a further_o explicate_v some_o observation_n about_o the_o globular_a figure_n and_o a_o experiment_n of_o reduce_v the_o file_n of_o tin_n or_o lead_v to_o exact_o round_a globule_n obseru._n 9_o of_o fantastical_a colour_n the_o texture_n of_o muscovy_n glass_n its_o figure_n what_o other_o body_n be_v like_o it_o that_o it_o exhibit_v several_a colour_n and_o how_o several_a observation_n and_o experiment_n about_o those_o colour_n the_o reason_n why_o on_o this_o occasion_n the_o nature_n of_o colour_n be_v inquire_v into_o a_o conjecture_n at_o the_o reason_n of_o these_o colour_n explicate_v by_o several_a experiment_n and_o reason_n first_o by_o continual_a cleave_v the_o body_n till_o it_o become_v colour_v second_o by_o produce_v all_o kind_n of_o colour_n with_o two_o flat_a plate_n of_o glass_n three_o by_o blow_v glass_n so_o thin_a in_o the_o lamp_n till_o it_o produce_v the_o same_o effect_n four_o by_o do_v the_o same_o with_o bubble_n of_o divers_a other_o transparent_a body_n the_o reason_n of_o the_o colour_n on_o nealed_a steel_n where_o by_o the_o way_n the_o cause_n of_o the_o harden_v and_o temper_v of_o steel_n endeavour_v to_o be_v show_v and_o explicate_v by_o several_a reason_n and_o experiment_n the_o reason_n of_o the_o colour_n on_o lead_n brass_n copper_n silver_n etc._n etc._n other_o instance_n of_o such_o colour_a body_n in_o animal_n substance_n several_a other_o distinguish_a observation_n des_fw-mi cartes_n hypothesis_n of_o colour_n examine_v a_o hypothesis_n for_o the_o explication_n of_o light_n by_o motion_n endeavour_v to_o be_v explicate_v and_o determine_v by_o several_a reason_n and_o experiment_n three_o distinguish_a property_n of_o the_o motion_n of_o light_n the_o distinguish_a property_n of_o a_o transparent_a medium_fw-la that_o there_o seem_v to_o be_v no_o experiment_n that_o prove_v the_o instantaneous_a motion_n of_o light_n the_o manner_n of_o the_o propagation_n of_o light_n through_o they_o of_o the_o homogeniety_n and_o heterogeniety_n of_o transparent_a medium_n and_o what_o effect_n they_o cause_n on_o the_o ray_n of_o light_n explicate_v by_o a_o figure_n a_o examination_n of_o the_o refraction_n of_o the_o ray_n by_o a_o plain_a surface_n which_o cause_v colour_n a_o examination_n of_o the_o like_a effect_n produce_v by_o a_o spherical_a surface_n the_o use_n that_o may_v be_v make_v of_o these_o experiment_n for_o the_o examination_n of_o several_a hyphothese_n of_o colour_n des_fw-mi cartes_n hypothesis_n examine_v some_o difficulty_n take_v notice_n of_o in_o it_o what_o seem_v most_o likely_a to_o be_v the_o cause_n of_o colour_n that_o propriety_n be_v endeavour_v to_o be_v show_v in_o a_o glass_n ball_n that_o the_o reflection_n be_v not_o necessary_a to_o produce_v colour_n nor_o a_o double_a refraction_n the_o hypothesis_n further_o examine_v both_o in_o the_o pellucid_n medium_fw-la and_o in_o the_o eye_n the_o definition_n of_o colour_n and_o a_o further_a explication_n and_o examination_n of_o the_o propriety_n of_o laminated_a body_n by_o what_o mean_v they_o conduce_v to_o the_o production_n of_o colour_n obseru._n 10._o of_o metalline_a colour_n that_o all_o colour_n seem_v to_o be_v cause_v by_o refraction_n a_o hypothesis_n consonant_n hereunto_o explicate_v by_o figure_n how_o several_a experiment_n of_o the_o sudden_a change_n of_o colour_n by_o chemical_a liquor_n may_v be_v hereby_o explicate_v how_o many_o way_n such_o chemical_a liquor_n may_v alter_v the_o colour_n of_o body_n objection_n make_v against_o this_o hypothesis_n of_o two_o colour_n only_o endeavour_v to_o be_v answer_v by_o several_a reason_n and_o experiment_n the_o reason_n why_o some_o colour_n be_v capable_a of_o be_v dilute_v other_o not_o what_o those_o be_v that_o probable_o the_o particle_n of_o most_o metalline_a colour_n be_v transparent_a for_o this_o several_a argument_n and_o observation_n be_v recite_v how_o colour_n become_v incapable_a of_o dilute_v explicate_v by_o
be_v yet_o find_v any_o thing_n perfect_o cold_a nor_o can_v i_o believe_v indeed_o that_o there_o be_v any_o such_o thing_n in_o nature_n as_o a_o body_n who_o particle_n be_v at_o rest_n or_o lazy_a and_o unactive_a in_o the_o great_a theatre_n of_o the_o world_n it_o be_v quite_o contrary_a to_o the_o grand_a oeconomy_n of_o the_o universe_n we_o see_v therefore_o what_o be_v the_o reason_n of_o the_o sympathy_n or_o unite_n of_o some_o body_n together_o and_o of_o the_o antipathy_n or_o flight_n of_o other_o from_o each_o other_o for_o congruity_n seem_v nothing_o else_o but_o a_o sympathy_n and_o incongruity_n a_o antipathy_n of_o body_n hence_o similar_v body_n once_o unite_v will_v not_o easy_o part_v and_o dissimilar_v body_n once_o disjoin_v will_v not_o easy_o unite_v again_o from_o hence_o may_v be_v very_o easy_o deduce_v the_o reason_n of_o the_o suspension_n of_o water_n and_o quicksilver_n above_o their_o usual_a station_n as_o i_o shall_v more_o at_o large_a anon_o show_v these_o property_n therefore_o always_o the_o concomitant_n of_o fluid_a body_n produce_v these_o follow_a visible_a effect_n first_o they_o unite_z the_o part_n of_o a_o fluid_a to_o its_o similar_v solid_a or_o keep_v they_o separate_v from_o its_o dissimilar_v hence_o quicksilver_n will_v as_o we_o note_v before_o stick_v to_o gold_n silver_n tin_n lead_v etc._n etc._n and_o unite_v with_o they_o but_o roll_n off_o from_o wood_n stone_n glass_n etc._n etc._n if_o never_o so_o little_o situate_v out_o of_o its_o horizontal_a level_n and_o water_n that_o will_v wet_v salt_n and_o dissolve_v it_o will_v slip_v off_o from_o tallow_n or_o the_o like_a without_o at_o all_o adhere_n as_o it_o may_v likewise_o be_v observe_v to_o do_v upon_o a_o dusty_a superficies_n and_o next_o they_o cause_v the_o part_n of_o homogeneal_a fluid_a body_n ready_o to_o adhere_v together_o and_o mix_v and_o of_o heterogeneal_a to_o be_v exceed_o averse_a thereunto_o hence_o we_o find_v that_o two_o small_a drop_n of_o water_n on_o any_o superficies_n they_o can_v roll_n on_o will_n if_o they_o chance_v to_o touch_v each_o other_o ready_o unite_v and_o mix_v into_o one_o 3d._o drop_n the_o like_a may_v be_v observe_v with_o two_o small_a bowl_n of_o quicksilver_n upon_o a_o table_n or_o glass_n provide_v their_o surface_n be_v not_o dusty_a and_o with_o two_o drop_n of_o oil_n upon_o fair_a water_n etc._n etc._n and_o further_o water_n put_v unto_o wine_n salt_n water_n vinegar_n spirit_n of_o wine_n or_o the_o like_a do_v immediate_o especial_o if_o they_o be_v shake_v together_o disperse_v itself_o all_o over_o they_o hence_o on_o the_o contrary_a we_o also_o find_v that_o oil_n of_o tartar_n pour_v upon_o quicksilver_n and_o spirit_n of_o wine_n on_o that_o oil_n of_o turpentine_n on_o that_o spirit_n and_o air_n upon_o that_o oil_n though_o they_o be_v stop_v close_o up_o into_o a_o bottle_n and_o shake_v never_o so_o much_o they_o will_v by_o no_o mean_n long_o suffer_v any_o of_o their_o big_a part_n to_o be_v unite_v or_o include_v within_o any_o of_o the_o other_o liquor_n by_o which_o recite_v liquor_n may_v be_v plain_o enough_o represent_v the_o four_o peripatetical_a element_n and_o the_o more_o subtle_a aether_n above_o all_o from_o this_o property_n it_o be_v that_o a_o drop_n of_o water_n do_v not_o mingle_v with_o or_o vanish_v into_o air_n but_o be_v drive_v by_o that_o fluid_a equal_o protrude_a it_o on_o every_o side_n and_o force_v into_o as_o little_a a_o space_n as_o it_o 〈◊〉_d possible_o be_v contain_v in_o namely_o into_o a_o round_a globule_n so_o likewise_o a_o title_n air_n blow_v under_o the_o water_n be_v unite_v or_o thrust_v into_o a_o bubble_n by_o the_o ambient_fw-la water_n and_o a_o parcel_n of_o quicksilver_n enclose_v with_o air_n water_n or_o almost_o any_o other_o liquor_n be_v form_v into_o a_o round_a ball._n now_o the_o cause_n why_o all_o these_o include_v fluids_n new_o mention_v or_o as_o many_o other_o as_o be_v whole_o include_v within_o a_o heterogeneous_a fluid_fw-la be_v not_o exact_o of_o a_o spherical_a figure_n see_v that_o if_o cause_v by_o these_o principle_n only_o it_o can_v be_v of_o no_o other_o must_v proceed_v from_o some_o other_o kind_n of_o pressure_n against_o the_o two_o opposite_a flat_v side_n this_o adventitious_a or_o accidental_a pressure_n may_v proceed_v from_o divers_a cause_n and_o according_o must_v diversify_v the_o figure_n of_o the_o include_v heterogeneous_a fluid_n for_o see_v that_o a_o body_n may_v be_v include_v either_o with_o a_o fluid_a only_o or_o only_o with_o a_o solid_a or_o partly_o with_o a_o fluid_a and_o partly_o with_o a_o solid_a or_o partly_o with_o one_o fluid_a and_o partly_o with_o another_o there_o will_v be_v find_v a_o very_a great_a variety_n of_o the_o terminate_a surface_n much_o differ_v from_o a_o spherical_a according_a to_o the_o various_a resistance_n or_o pressure_n that_o belong_v to_o each_o of_o those_o encompass_v body_n which_o property_n may_v in_o general_n be_v deduce_v from_o two_o head_n viz._n motion_n and_o rest._n for_o either_o this_o globular_a figure_n be_v alter_v by_o a_o natural_a motion_n such_o as_o be_v gravity_n or_o a_o violent_a such_o as_o be_v any_o accidental_a motion_n of_o the_o fluid_n as_o we_o see_v in_o the_o wind_n ruffle_v up_o the_o water_n and_o the_o purl_n of_o stream_n and_o foam_v of_o cataract_n and_o the_o like_a of_o three_o by_o the_o rest_n firmness_n and_o stability_n of_o the_o ambient_fw-la solid_a for_o if_o the_o include_v solid_n be_v of_o a_o angular_a or_o any_o other_o irregular_a form_n the_o include_v fluid_a will_v be_v near_o of_o the_o like_a as_o a_o pint_n pot_n full_a of_o water_n or_o a_o bladder_n full_a of_o air._n and_o next_o if_o the_o including_z or_o include_v fluid_a have_v a_o great_a gravity_n one_o than_o another_o then_o will_v the_o globular_a form_n be_v depress_v into_o a_o ellipticospherical_a as_o if_o for_o example_n we_o suppose_v the_o circle_n abcd_n in_o the_o four_o figure_n to_o represent_v a_o drop_n of_o water_n quicksilver_n or_o the_o like_a include_v with_o the_o air_n or_o the_o like_a which_o suppose_v there_o be_v no_o gravity_n at_o all_o in_o either_o of_o the_o fluid_n or_o that_o the_o contain_v and_o contain_v be_v of_o the_o same_o weight_n will_v be_v equal_o compress_v into_o a_o exact_o spherical_a body_n the_o ambient_fw-la fluid_fw-la force_v equal_o against_o every_o side_n of_o it_o but_o suppose_v either_o a_o great_a gravity_n in_o the_o include_v by_o reason_n whereof_o the_o part_n of_o it_o be_v press_v from_o a_o towards_o b_o and_o thereby_o the_o whole_a put_v into_o motion_n and_o that_o motion_n be_v hinder_v by_o the_o resistance_n of_o the_o subjacent_a part_n of_o the_o ambient_fw-la the_o globular_a figure_n adbc_n will_v be_v depress_v into_o the_o ellipticospherical_a egfh_n for_o the_o side_n a_o be_v detrude_v to_o e_o by_o the_o gravity_n and_o b_o to_o f_o by_o the_o resistance_n of_o the_o subjacent_a medium_n and_o therefore_o c_z must_v neccessary_o be_v thrust_v to_o g_o and_o d_o to_z h._n or_o else_o suppose_v a_o great_a gravity_n in_o the_o ambient_fw-la by_o who_o more_o then_o ordinary_a pressure_n against_o the_o under_o side_n of_o the_o include_v globule_n e_o will_v be_v force_v to_o f_o and_o by_o its_o resistance_n of_o the_o motion_n upward_o the_o side_n a_o will_v be_v depress_v to_o e_o and_o therefore_o c_o be_v thrust_v to_o g_z and_o d_o to_o h_n the_o globular_a figure_n by_o this_o mean_n also_o will_v be_v make_v a_o ellipticospherical_a next_o if_o a_o fluid_a be_v include_v partly_o with_o one_o and_o partly_o with_o another_o fluid_a it_o will_v be_v find_v to_o be_v shape_v diverse_o according_a to_o the_o proportion_n of_o the_o gravity_n and_o incongruity_n of_o the_o 3_o fluid_n one_o to_o another_o as_o in_o the_o second_o figure_n let_v the_o upper_a mmm_o be_v air_n the_o middle_a lmno_n be_v common_a oil_n the_o low_a ooo_o be_v water_n the_o oil_n will_v be_v form_v not_o into_o a_o spherical_a figure_n such_o as_o be_v represent_v by_o the_o prick_a line_n but_o into_o such_o a_o figure_n as_o lmno_n who_o side_n lmn_n will_v be_v of_o a_o flatter_v elliptical_a figure_n by_o reason_n of_o the_o great_a disproportion_n between_o the_o gravity_n of_o oil_n and_o air_n and_o the_o side_n lom_n of_o a_o round_a because_o of_o the_o small_a difference_n between_o the_o weight_n of_o oil_n and_o water_n last_o the_o globular_a figure_n will_v be_v change_v if_o the_o ambient_fw-la be_v partly_o fluid_a and_o partly_o solid_a and_o here_o the_o termination_n of_o the_o encompass_v fluid_a towards_o the_o encompass_v be_v shape_v according_a to_o the_o proportion_n of_o the_o congruity_n or_o incongruity_n of_o the_o fluid_n to_o the_o solid_n and_o
perceive_v the_o perforation_n with_o one_o naked_a eye_n though_o by_o the_o help_n of_o a_o microscope_n it_o may_v easy_o enough_o be_v perceive_v nay_o i_o have_v make_v a_o pipe_n perforate_v from_o end_n to_o end_n so_o small_a that_o with_o my_o naked_a eye_n i_o can_v very_o hardly_o see_v the_o body_n of_o it_o insomuch_o that_o i_o have_v be_v able_a to_o knit_v it_o up_o into_o a_o knot_n without_o break_v and_o more_o accurate_o examine_v one_o with_o my_o microscope_n i_o find_v it_o not_o so_o big_a as_o a_o sixteen_o part_n of_o one_o of_o the_o small_a hair_n of_o my_o head_n which_o be_v of_o the_o small_a and_o fine_a sort_n of_o hair_n so_o that_o sixteen_o of_o these_o pipe_n bind_v faggot-wiâ—e_a together_o will_v but_o have_v equalise_v one_o single_a hair_n how_o small_a therefore_o must_v its_o perforation_n be_v it_o appear_v to_o i_o through_o the_o microscope_n to_o be_v a_o proportionable_o thick-sided_n pipe_n to_o proceed_v then_o for_o the_o trial_n of_o the_o experiment_n the_o experimenter_n must_v place_v the_o tube_n ab_fw-la perpendicular_a and_o fill_v the_o pipe_n f_o cement_v into_o the_o hole_n e_o with_o water_n but_o leave_v the_o bubble_n c_o bookful_n of_o air_n and_o then_o gentle_o pour_v in_o water_n into_o the_o pipe_n ab_fw-la he_o must_v observe_v diligent_o how_o high_a the_o water_n will_v rise_v in_o it_o before_o it_o protrude_v the_o bubble_n of_o air_n c_o through_o the_o narrow_a passage_n of_o f_o and_o denote_v exact_o the_o height_n of_o the_o cylinder_n of_o water_n then_o cement_n in_o a_o second_o pipe_n as_o g_o and_o fill_v it_o with_o water_n he_o may_v proceed_v as_o with_o the_o former_a denote_v likewise_o the_o height_n of_o the_o cylinder_n of_o water_n able_a to_o protrude_v the_o bubble_n c_o through_o the_o passage_n of_o g_o the_o like_a may_v he_o do_v with_o the_o next_o pipe_n and_o the_o next_o etc._n etc._n as_o far_o as_o he_o be_v able_a then_o compare_v the_o several_a height_n of_o the_o cylinder_n with_o the_o several_a hole_n through_o which_o each_o cylinder_n do_v force_v the_o air_n have_v due_a regard_n to_o the_o cylinder_n of_o water_n in_o the_o small_a tube_n it_o will_v be_v very_o easy_a to_o determine_v what_o force_n be_v requisite_a to_o press_v the_o air_n into_o such_o and_o such_o a_o hole_n or_o to_o apply_v it_o to_o our_o present_a experiment_n how_o much_o of_o the_o pressure_n of_o the_o air_n be_v take_v off_o by_o its_o ingress_n into_o small_a and_o small_a hole_n from_o the_o application_n of_o which_o to_o the_o enter_v of_o the_o air_n into_o the_o big_a hole_n of_o the_o vessel_n and_o into_o the_o small_a hole_n of_o the_o pipe_n we_o shall_v clear_o find_v that_o there_o be_v a_o great_a pressure_n of_o the_o air_n upon_o the_o water_n in_o the_o vessel_n or_o great_a pipe_n than_o there_o be_v upon_o that_o in_o the_o lesser_a pipe_n for_o since_o the_o pressure_n of_o the_o air_n every_o way_n be_v find_v to_o be_v equal_a that_o be_v as_o much_o as_o be_v able_a to_o press_v up_o and_o sustain_v a_o cylinder_n of_o quicksilver_n of_o two_o foot_n and_o a_o half_a high_a or_o thereabouts_o and_o since_o of_o this_o pressure_n so_o many_o more_o degree_n be_v require_v to_o force_v the_o air_n into_o a_o small_a than_o into_o a_o great_a hole_n that_o be_v full_a of_o a_o more_o congruous_a fluid_n and_o last_o since_o those_o degree_n that_o be_v requisite_a to_o press_v it_o in_o be_v thereby_o take_v off_o from_o the_o air_n within_o and_o the_o air_n within_o leave_v with_o so_o many_o degree_n of_o pressure_n less_o than_o the_o air_n without_o it_o will_v follow_v that_o the_o air_n in_o the_o less_o tube_n or_o pipe_n will_v have_v less_o pressure_n against_o the_o superficies_n of_o the_o water_n therein_o than_o the_o air_n in_o the_o big_a which_o be_v the_o minor_a proposition_n to_o be_v prove_v the_o conclusion_n therefore_o will_v necessary_o follow_v viz._n that_o this_o unequal_a pressure_n of_o the_o air_n cause_v by_o its_o ingress_n into_o unequal_a hole_n be_v a_o cause_n sufficient_a to_o produce_v this_o effect_n without_o the_o help_n of_o any_o other_o concurrent_a and_o therefore_o be_v probable_o the_o principal_n if_o not_o the_o only_a cause_n of_o these_o phaenomena_n this_o therefore_o be_v thus_o explain_v there_o will_v be_v divers_a phaenomena_n explicable_a thereby_o as_o the_o rise_n of_o liquor_n in_o a_o filtre_n the_o rise_n of_o spirit_n of_o wine_n oil_n melt_v tallow_n etc._n etc._n in_o the_o week_n of_o a_o lamp_n though_o make_v of_o small_a wire_n thread_n of_o asbestus_n string_n of_o glass_n or_o the_o like_a the_o rise_n of_o liquor_n in_o a_o sponge_n piece_n of_o bread_n sand_n etc._n etc._n perhaps_o also_o the_o ascend_a of_o the_o sap_n in_o tree_n and_o plant_n through_o their_o small_a and_o some_o of_o they_o imperceptible_a pore_n of_o which_o i_o have_v say_v more_o on_o another_o occasion_n at_o least_o the_o pass_v of_o it_o out_o of_o the_o earth_n into_o their_o root_n and_o indeed_o upon_o the_o consideration_n of_o this_o principle_n multitude_n of_o other_o use_n of_o it_o occur_v to_o i_o which_o i_o have_v not_o yet_o so_o well_o examine_v and_o digest_v as_o to_o propound_v for_o axiom_n but_o only_o as_o query_n and_o conjecture_n which_o may_v serve_v as_o hint_n towards_o some_o further_a discovery_n as_o first_o upon_o the_o consideration_n of_o the_o congruity_n and_o incongruity_n of_o body_n as_o to_o touch_v i_o find_v also_o the_o like_a congruity_n and_o incongruity_n if_o i_o may_v so_o speak_v as_o to_o the_o transmit_v of_o the_o ray_n of_o light_n for_o as_o in_o this_o regard_n water_n not_o now_o to_o mention_v other_o liquor_n seem_v near_o of_o affinity_n to_o glass_n then_o air_n and_o air_n than_o quicksilver_n whence_o a_o oblique_a ray_n out_o of_o glass_n will_v pass_v into_o water_n with_o very_o little_a refraction_n from_o the_o perpendicular_a but_o none_o out_o of_o glass_n into_o air_n except_v a_o direct_a will_v pass_v without_o a_o very_a great_a refraction_n from_o the_o perpendicular_a nay_o any_o oblique_a ray_n under_o thirty_o degree_n will_v not_o be_v admit_v into_o the_o air_n at_o all_o and_o quicksilver_n will_v neither_o admit_v oblique_a or_o direct_a but_o reflect_v all_o seem_v as_o to_o the_o transmit_v of_o the_o ray_n of_o light_n to_o be_v of_o a_o quite_o differ_v constitution_n from_o that_o of_o air_n water_n glass_n etc._n etc._n and_o to_o resemble_v most_o those_o opacous_a and_o strong_a reflect_a body_n of_o metal_n so_o also_o as_o to_o the_o property_n of_o cohesion_n or_o congruity_n water_n seem_v to_o keep_v the_o same_o order_n be_v more_o congruous_a to_o glass_n then_o air_n and_o air_n than_o quicksilver_n a_o second_o thing_n which_o be_v hint_v to_o i_o by_o the_o consideration_n of_o the_o include_v fluid_n globular_a form_n cause_v by_o the_o protrusion_n of_o the_o ambient_fw-la heterogeneous_a fluid_n be_v 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answer_v all_o the_o objection_n many_o whereof_o i_o foresee_v that_o may_v be_v allege_v against_o it_o i_o shall_v at_o present_a proceed_v to_o other_o query_n content_v myself_o to_o have_v here_o only_o give_v a_o hint_n of_o what_o i_o may_v say_v more_o elsewhere_o a_o three_o query_n than_o be_v whether_o the_o heterogeneity_n of_o the_o ambient_fw-la fluid_fw-la may_v not_o be_v account_v a_o secondary_a cause_n of_o the_o roundness_n or_o globular_a form_n of_o the_o great_a body_n of_o the_o world_n such_o as_o be_v those_o of_o the_o sun_n star_n and_o planet_n the_o substance_n of_o each_o of_o which_o seem_v altogether_o heterogeneous_a to_o the_o circum-ambient_a fluid_a aether_n and_o of_o this_o i_o shall_v say_v more_o in_o the_o observation_n of_o the_o moon_n a_o four_o be_v
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for_o i_o have_v find_v by_o a_o most_o certain_a experiment_n which_o i_o exhibit_v before_o divers_a illustrious_a person_n of_o the_o royal_a society_n that_o the_o refraction_n of_o water_n be_v great_a than_o that_o of_o ice_n though_o some_o considerable_a author_n have_v affirm_v the_o contrary_a and_o though_o the_o ice_n be_v a_o very_a hard_a and_o the_o water_n a_o very_a fluid_a body_n that_o the_o former_a of_o the_o two_o precede_a proposition_n be_v true_a may_v be_v manifest_v by_o several_a experiment_n as_o first_o if_o you_o take_v any_o two_o liquor_n differ_v from_o one_o another_o in_o density_n but_o yet_o such_o as_o will_v ready_o mix_v as_o salt_n water_n or_o brine_n &_o fresh_a almost_o any_o kind_n of_o salt_n dissolve_v in_o water_n and_o filtrate_v so_o that_o it_o be_v clear_a spirit_n of_o wine_n and_o water_n nay_o spirit_n of_o wine_n and_o spirit_n of_o wine_n one_o more_o high_o rectify_v then_o the_o other_o and_o very_o many_o other_o liquor_n 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phaenomena_n for_o i_o shall_v take_v notice_n of_o no_o more_o at_o present_a though_o i_o can_v instance_n in_o multitude_n of_o other_o must_v necessary_o be_v cause_v by_o a_o inflection_n of_o the_o ray_n within_o the_o terminate_a superficies_n of_o the_o compound_a medium_n since_o the_o surface_n of_o the_o transparent_a body_n through_o which_o the_o ray_n pass_v to_o the_o eye_n be_v not_o at_o all_o alter_v or_o change_v this_o inflection_n if_o i_o may_v so_o call_v it_o i_o imagine_v to_o be_v nothing_o else_o but_o a_o multiplicate_v refraction_n cause_v by_o the_o unequal_a density_n of_o the_o constituent_a part_n of_o the_o medium_n whereby_o the_o motion_n action_n or_o progress_n of_o the_o ray_n of_o light_n be_v hinder_v from_o proceed_v in_o a_o straight_a line_n and_o inflect_v or_o deflect_v by_o a_o curve_v
now_o that_o it_o be_v a_o curve_v line_n be_v manifest_a by_o this_o experiment_n i_o take_v a_o box_n such_o as_o adge_v in_o the_o first_o figure_n of_o the_o 37._o scheme_n who_o side_n abcd_v and_o efgh_a be_v make_v of_o two_o smooth_a flat_a plate_n of_o glass_n then_o fill_v it_o half_o full_a with_o a_o very_a strong_a solution_n of_o salt_n i_o fill_v the_o other_o half_a with_o very_o fair_a fresh_a water_n then_o expose_v the_o opacous_a side_n dhgc_a to_o the_o sun_n i_o observe_v both_o the_o refraction_n and_o inflection_n of_o the_o sun_n beam_n id_fw-la &_o kh_n and_o mark_v as_o exact_o as_o i_o can_v the_o point_n p_o n_o o_o m_o by_o which_o the_o ray_n kh_n pass_v through_o the_o compound_a medium_n i_o find_v they_o to_o be_v in_o a_o curve_v line_n for_o the_o part_n of_o the_o medium_n be_v continual_o more_o dense_a the_o near_o they_o be_v to_o the_o bottom_n the_o ray_n pf_o be_v continual_o more_o and_o more_o deflect_v downward_o from_o the_o straight_a line_n schem_n xxxvii_o i_o can_v produce_v many_o more_o example_n and_o experiment_n to_o illustrate_v and_o prove_v this_o first_o proposition_n viz._n that_o there_o be_v such_o a_o constitution_n of_o some_o body_n as_o will_v cause_v inflection_n as_o not_o to_o mention_v those_o i_o have_v observe_v in_o horn_n tortoise-shell_n transparent_a gum_n and_o resinous_a substance_n the_o vein_n of_o glass_n nay_o of_o melt_a crystal_n find_v and_o much_o complain_v of_o by_o glass-grinder_n and_o other_o may_v sufficient_o demonstrate_v the_o truth_n of_o it_o to_o any_o diligent_a observator_fw-la but_o that_o i_o presume_v i_o have_v by_o this_o example_n give_v proof_n sufficient_a viz._n ocular_a demonstration_n to_o evince_v that_o there_o be_v such_o a_o modulation_n or_o bend_v of_o the_o ray_n of_o light_n as_o i_o have_v call_v inflection_n differ_v both_o from_o reflection_n and_o refraction_n since_o they_o be_v both_o make_v in_o the_o superficies_n this_o only_a in_o 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you_o make_v trial_n of_o this_o experiment_n take_v a_o small_a glass-bubble_n make_v in_o the_o form_n of_o that_o in_o the_o second_o figure_n of_o the_o 37._o scheme_n and_o by_o heat_n the_o glass_n very_o hot_a and_o thereby_o very_a much_o rarify_n the_o include_v air_n or_o which_o be_v better_o by_o rarify_n a_o small_a quantity_n of_o water_n include_v in_o it_o into_o vapour_n which_o will_v expel_v the_o most_o part_n if_o not_o all_o the_o air_n and_o then_o seal_v up_o the_o small_a neck_n of_o it_o and_o let_v it_o cool_a you_o may_v find_v if_o you_o place_v it_o in_o a_o convenient_a instrument_n that_o there_o will_v be_v a_o manifest_a difference_n as_o to_o the_o refraction_n as_o if_o in_o this_o second_o figure_n you_o suppose_v a_o to_o represent_v a_o small_a sight_n or_o hole_n through_o which_o the_o eye_n look_v upon_o a_o object_n as_o c_o through_o the_o glass-bubble_n b_o and_o the_o second_o sight_n l_o all_o which_o remain_v exact_o fix_v in_o their_o 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of_o the_o medium_n contain_v in_o the_o glass_n b_o the_o great_a difficulty_n in_o the_o make_n of_o which_o experiment_n be_v from_o the_o uneven_a surface_n of_o the_o bubble_n which_o will_v represent_v a_o uneven_a image_n of_o the_o object_n now_o that_o there_o be_v such_o a_o difference_n of_o the_o upper_a and_o under_o part_n of_o the_o air_n be_v clear_a enough_o evince_v from_o the_o late_a improvement_n of_o the_o torricellian_a experiment_n which_o have_v be_v try_v at_o the_o top_n and_o foot_n of_o mountain_n and_o may_v be_v further_o illustrate_v and_o inquire_v into_o by_o a_o mean_n which_o some_o while_n since_o i_o think_v of_o and_o use_v for_o the_o find_n by_o what_o degree_n the_o air_n pass_v from_o such_o a_o degree_n of_o density_n to_o such_o a_o degree_n of_o rarity_n and_o another_o for_o the_o find_v what_o pressure_n be_v requisite_a to_o make_v it_o pass_v from_o such_o a_o degree_n of_o rarefaction_n to_o a_o determinate_a density_n which_o 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