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the_o heavy_a body_n force_v up_o the_o less_o heavy_a as_o fire_n do_v air_n but_o also_o the_o more_o heavy_a as_o water_n in_o respect_n of_o air_n when_o ever_o it_o be_v make_v light_a by_o the_o interspersion_n of_o fiery_a particle_n and_o this_o he_o seem_v design_o to_o insinuate_v in_o the_o above-cited_n dialogue_n of_o timaeus_n when_o he_o say_v that_o the_o fire_n rise_v from_o the_o hot_a entrail_n of_o the_o earth_n and_o not_o enter_v into_o a_o vacuity_n thrust_v forward_o the_o air_n that_o be_v contiguous_a to_o it_o which_o not_o only_o give_v way_n thereto_o but_o even_o dive_v it_o of_o those_o moist_a particle_n wherewith_o it_o ascend_v and_o then_o help_v it_o forward_o and_o raise_v it_o up_o unto_o
of_o our_o proceedure_n let_v that_o freedom_n suffice_v wherewith_o we_o have_v still_o communicate_v the_o essay_n and_o experiment_n themselves_o to_o any_o that_o travel_v by_o our_o country_n show_v any_o desire_n or_o relish_v of_o such_o science_n move_v either_o by_o a_o gentile_a humour_n esteem_v of_o learning_n or_o spur_v of_o curiosity_n and_o that_o from_o the_o first_o time_n our_o academy_n be_v found_v in_o the_o year_n 1657_o when_o the_o great_a part_n if_o not_o all_o the_o experiment_n be_v invent_v whereof_o these_o essay_n be_v now_o publish_v if_o it_o shall_v happen_v that_o among_o they_o there_o shall_v be_v any_o find_v think_v of_o before_o or_o after_o the_o time_n they_o be_v make_v here_o by_o other_o person_n and_o make_v public_a let_v we_o not_o be_v blame_v for_o it_o since_o we_o can_v neither_o know_v nor_o see_v all_o thing_n so_o that_o no_o man_n ought_v to_o wonder_v at_o the_o lucky_a accord_n of_o our_o mind_n and_o invention_n with_o other_o 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transition_n from_o one_o experiment_n to_o another_o or_o upon_o what_o occasion_n soever_o there_o shall_v be_v insert_v any_o hint_n of_o speculation_n we_o request_v they_o may_v be_v take_v always_o for_o the_o thought_n and_o particular_a sense_n of_o some_o one_o of_o the_o member_n but_o not_o impute_v to_o the_o whole_a academy_n who_o sole_a design_n be_v to_o make_v experiment_n and_o relate_v they_o for_o such_o be_v our_o first_o proposal_n and_o the_o intent_n of_o that_o great_a personage_n who_o with_o his_o particular_a protection_n and_o far-reaching_a judgement_n cause_v we_o to_o take_v that_o method_n to_o which_o sage_n and_o prudent_a advice_n we_o have_v still_o punctual_o and_o regular_o conform_v the_o content_n the_o description_n of_o some_o instrument_n to_o discover_v the_o alteration_n of_o the_o air._n page_n 1_o the_o description_n of_o instrument_n to_o measure_v time_n 10_o experiment_n appertain_v to_o the_o natural_a pressure_n of_o the_o air_n 13_o that_o the_o pressure_n of_o the_o air_n sustain_v the_o quicksilver_n in_o the_o tube_n 14_o mr._n roberval_n exper._n of_o the_o air_n pressure_n repeat_v 17_o experiment_n against_o the_o air_n pressure_n answer_v 19_o whether_o the_o air_n gravitates_fw-la and_o of_o its_o expansion_n 22_o when_o the_o pressure_n be_v take_v off_o that_o the_o mercury_n fall_v with_o other_o experiment_n relate_v thereto_o 24_o etc._n etc._n the_o efficacy_n of_o another_o fluid_a join_v to_o the_o air_n pressure_n 30_o several_a experiment_n about_o the_o air_n pressure_n to_o 34_o the_o description_n of_o instrument_n show_v the_o alteration_n happen_v in_o the_o state_n of_o the_o natural_a compression_n of_o the_o air_n 35_o various_a experiment_n make_v in_o vacuo_fw-la 40_o of_o the_o spherical_a figure_n of_o small_a drop_n in_o vacuo_fw-la ib._n of_o heat_n and_o cold_a apply_v outward_o to_o the_o vacuum_n 41_o whether_o the_o air_n reflect_v the_o second_o image_n visible_a in_o a_o lens_fw-la 42_o of_o amber_n in_o vacuo_fw-la 43_o of_o the_o effluvia_fw-la of_o fire_n in_o vacuo_fw-la 46_o of_o the_o motion_n of_o smoke_n in_o vacuo_fw-la 48_o of_o sound_n in_o vacuo_fw-la 50_o of_o the_o magnet_n in_o vacuo_fw-la 53_o of_o hollow_a cane_n in_o vacuo_fw-la ib._n of_o the_o boil_a of_o water_n in_o vacuo_fw-la 57_o of_o snow_n in_o vacuo_fw-la 58_o of_o the_o dissolution_n of_o pearl_n and_o coral_n in_o vacuo_fw-la 59_o of_o several_a animal_n include_v in_o vacuo_fw-la 61_o etc._n etc._n of_o bladder_n of_o small_a fish_n in_o vacuo_fw-la 66_o experiment_n of_o artificial_a freeze_v 69_o of_o the_o dilatation_n of_o water_n in_o freeze_a 71_o of_o the_o measure_n of_o the_o force_n of_o rarifaction_n in_o freeze_a water_n 77_o to_o measure_n the_o utmost_a expansion_n in_o freeze_a water_n 79_o of_o the_o procedure_n of_o artificial_a freezing_n 77_o table_n of_o several_a fluids_n freeze_a 83_o etc._n etc._n experiment_n of_o natural_a freeze_v 95_o of_o common_a water_n in_o air_n ib._n of_o the_o same_o in_o vacuo_fw-la 98_o of_o still_v water_n 99_o of_o sea_n water_n ib._n of_o the_o power_n of_o sal_fw-la ammoniac_a etc._n etc._n in_o freezing_n 100_o of_o the_o metal_n that_o keep_v ice_n best_o 101_o of_o freeze_a a_o pieee_o of_o ice_n to_o a_o table_n ib._n of_o freeze_v the_o dew_n upon_o the_o outside_n of_o glass_n 102_o of_o reflect_v cold_a 103_o experiment_n about_o the_o alteration_n of_o the_o size_n of_o vessel_n etc._n etc._n by_o heat_n &_o cold_a 104_o that_o the_o vessel_n alter_v before_o the_o liquor_n contain_v 105_o of_o the_o alteration_n of_o a_o brass_n ring_n by_o heat_n in_o the_o fire_n 107_o of_o body_n dilate_v by_o imbibe_v moisture_n 108_o of_o the_o dilate_v and_o contract_n of_o glass_n by_o heat_n and_o cold_a 109_o of_o the_o same_o in_o tinn_n 110_o in_o brass_n wire_n 111_o the_o same_o prove_v by_o a_o different_a observable_a 112_o that_o a_o vessel_n also_o may_v be_v distend_v by_o weight_n 113_o experiment_n about_o the_o compression_n of_o water_n 114_o etc._n etc._n experiment_n against_o positive_a levity_n 118_o experiment_n magnetical_a 123_o about_o divert_v the_o passage_n of_o the_o magnetic_a virtue_n 124_o about_o the_o magnetic_a virtue_n pass_v through_o divers_a fluids_n 125_o about_o the_o place_v the_o magnetic_a in_o respect_n of_o the_o pole_n of_o the_o earth_n 127_o experiment_n touch_v amber_n and_o other_o electic_a body_n 128_o experiment_n about_o alter_v the_o colour_n of_o several_a fluids_n 133_o of_o alter_a water_n ib._n of_o alter_a wine_n 135_o of_o alter_a a_o tincture_n of_o red_a rose_n ib._n of_o alter_a a_o tincture_n of_o saffron_n 136_o of_o alter_a green_n ib._n of_o alter_a violet_n colour_n 137_o experiment_n about_o the_o motion_n of_o sound_n 138_o of_o sound_n pass_v equal_a space_n in_o equal_a time_n ib._n of_o contrary_a and_o favour_a wind_n 140_o of_o the_o equability_n of_o motion_n in_o sound_n ib._n experiment_n about_o body_n project_v 143_o of_o horizontal_a shot_n from_o the_o top_n of_o a_o tower_n ib._n of_o perpendicular_a shot_n 144_o motion_n impress_v not_o alter_v by_o a_o new_a direction_n 145_o miscellaneous_n experiment_n 147_o of_o the_o absolute_a weight_n of_o air_n to_o water_n ib._n of_o heat_n and_o cold_a of_o a_o wire_n seem_v light_a hot_a than_o cold_a 149_o of_o the_o force_n of_o heat_n in_o rarifaction_n 150_o of_o antiperistasis_n 151_o whether_o cold_a be_v cause_v by_o the_o intrusion_n of_o frigorific_a atom_n 152_o of_o ebullition_n by_o salt_n etc._n etc._n 153_o whether_o glass_n be_v penetrable_a by_o odour_n 155_o whether_o glass_n be_v penetrable_a by_o humidity_n 156_o experiment_n of_o light_n of_o the_o instantaneous_a motion_n of_o light_n 157_o of_o fire_v body_n with_o a_o burn_a glass_n 158_o of_o body_n afford_v light_a ib._n experiment_n about_o the_o digestion_n of_o some_o animal_n 160_o tab._n 1._o p._n 1._o the_o description_n of_o some_o instrument_n to_o discover_v the_o alteration_n of_o the_o air_n cause_v by_o heat_n and_o cold_a it_o be_v most_o useful_a and_o indeed_o a_o necessary_a thing_n in_o the_o make_n of_o natural_a experiment_n to_o be_v true_o inform_v of_o all_o the_o alteration_n the_o air_n be_v incident_a to_o for_o since_o it_o receive_v into_o itself_o and_o as_o it_o be_v embraces_z all_o thing_n lean_v on_o they_o with_o its_o whole_a weight_n from_o a_o vast_a height_n they_o must_v needs_o all_o bend_v under_o this_o pressure_n and_o as_o this_o violence_n which_o they_o suffer_v be_v more_o or_o less_o so_o be_v they_o more_o imprison_v or_o enlarge_v thus_o the_o mercurial_a standard_n either_o rise_v or_o fall_v at_o the_o different_a height_n of_o the_o atmosphere_n or_o as_o some_o think_v correspondent_a to_o the_o various_a temperament_n which_o the_o air_n receive_v from_o the_o sun_n or_o from_o the_o shade_n from_o the_o
the_o air_n keep_v in_o the_o same_o state_n of_o compression_n as_o it_o be_v force_v to_o do_v from_o the_o resistance_n make_v by_o the_o glass_n bell_n and_o cement_n which_o supply_v the_o place_n of_o all_o that_o vast_a tract_n of_o incumbent_n air._n and_o because_o it_o be_v yet_o believe_v by_o some_o that_o the_o force_n of_o a_o suppose_a spring_n in_o the_o air_n act_v whole_o in_o this_o effect_n so_o as_o without_o it_o by_o no_o mean_n it_o can_v happen_v it_o be_v therefore_o attempt_v to_o insinuate_v the_o contrary_a by_o the_o follow_a experiment_n take_v the_o same_o vessel_n ab_fw-la with_o its_o cane_n of_o before_o we_o pour_v off_o any_o of_o the_o mercury_n as_o be_v direct_v in_o the_o former_a experiment_n or_o stop_v up_o the_o mouth_n of_o the_o vessel_n at_o a_o with_o cement_n and_o then_o set_v all_o in_o a_o great_a vessel_n full_a of_o water_n klmn_n the_o quicksilver_n be_v observe_v to_o be_v sensible_o depress_v from_o a_o to_o gh_v and_o on_o the_o contrary_a raise_v in_o the_o cane_n from_o i_o to_o o_o this_o ascent_n be_v about_o the_o fourteen_o part_n of_o the_o whole_a height_n of_o the_o water_n of_o then_o the_o mouth_n a_o be_v close_v that_o so_o only_a the_o water_n in_o the_o space_n agh_o may_v press_v upon_o the_o mercury_n which_o nevertheless_o lose_v none_o of_o the_o height_n late_o gain_v by_o the_o weight_n of_o all_o the_o incumbent_a water_n of_o above_o the_o first_o level_v i_o yet_o in_o this_o case_n the_o include_v water_n agh_o not_o by_o virtue_n of_o any_o spring_n which_o perchance_o it_o have_v not_o but_o because_o it_o have_v be_v force_v by_o the_o charge_n of_o the_o whole_a height_n of_o into_o the_o space_n leave_v by_o the_o quicksilver_n rise_v from_o i_o to_o o_o and_o keep_v there_o by_o the_o same_o force_n and_o so_o hinder_v from_o return_v the_o same_o may_v be_v say_v to_o happen_v to_o the_o air._n last_o some_o desirous_a to_o see_v what_o effect_v a_o great_a or_o lesser_a 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from_o all_o which_o matter_n it_o seem_v probable_a that_o this_o sustention_n of_o the_o fluid_n do_v not_o absolute_o depend_v upon_o the_o weight_n of_o the_o air_n but_o also_o upon_o the_o compression_n which_o low_a part_n of_o the_o air_n receive_v from_o those_o above_o a_o experiment_n to_o know_v if_o the_o air_n near_o the_o superficies_n of_o the_o earth_n be_v press_v by_o the_o weight_n of_o the_o air_n above_o and_o if_o it_o be_v put_v in_o a_o void_a space_n at_o its_o liberty_n whether_o it_o will_v expand_v itself_o to_o a_o great_a space_n and_o how_o much_o when_o yet_o it_o be_v still_o unaltered_a by_o any_o new_a degree_n of_o heat_n the_o ingenious_a observation_n make_v by_o m._n roberval_n with_o the_o little_a bladder_n of_o air_n enlarge_n itself_o in_o vacuo_fw-la move_v some_o to_o believe_v it_o may_v be_v determine_v how_o far_o the_o air_n be_v capable_a of_o expansion_n when_o at_o absolute_a liberty_n in_o any_o place_n for_o it_o seem_v probable_a to_o they_o that_o in_o any_o vessel_n propose_v a_o void_a space_n may_v be_v assign_v sufficient_a for_o the_o whole_a increase_n of_o such_o a_o quantity_n of_o air_n whence_o whatever_n shall_v happen_v to_o exceed_v that_o quantity_n require_v a_o more_o ample_a space_n to_o dilate_v itself_o in_o must_v proportionable_o more_o or_o less_o depress_v the_o mercurial_a cilind_a below_o the_o usual_a height_n of_o about_o 28_o inch_n and_o on_o the_o other_o side_n what_o ever_o come_v short_a of_o it_o will_v easy_o permit_v the_o mercury_n to_o rise_v to_o the_o usual_a height_n the_o experiment_n be_v thus_o brac._n let_v there_o be_v a_o vessel_n of_o glass_n abc_n with_o a_o shank_n bc_n about_o 46_o inch_n long_o open_a at_o g_z and_o let_v there_o be_v a_o tall_a glass_n provide_v def_n fill_v with_o mercury_n to_o immerse_n the_o shank_n bc_n into_o but_o such_o a_o vessel_n as_o may_v not_o only_o serve_v to_o immerse_v it_o into_o but_o capable_a when_o desire_v of_o receive_v either_o all_o or_o a_o great_a part_n of_o the_o shank_n into_o itself_o as_o a_o scabbard_n 4._o let_v there_o be_v another_o vessel_n ghi_n equal_a in_o all_o respect_n as_o near_o as_o may_v be_v to_o the_o former_a abc_n in_o which_o make_v the_o usual_a vacuum_n mark_v the_o height_n to_o which_o the_o mercury_n be_v sustain_v at_o that_o time_n kl_n then_o fill_v with_o mercury_n the_o vessel_n abc_n fig._n 3._o be_v as_o be_v say_v of_o the_o same_o size_n by_o the_o mouth_n c_o up_z to_o m_o and_o let_v mc_n remain_v fill_v with_o air._n it_o be_v clear_a that_o stop_v with_o your_o finger_n the_o mouth_n c_o and_o invert_v the_o vessel_n the_o small_a quantity_n of_o air_n leave_v mc_n will_v pass_v through_o the_o mercury_n and_o take_v its_o place_n in_o a._n then_o plunge_v the_o mouth_n c_o beneath_o the_o level_n of_o the_o stagnant_a mercury_n df_n and_o remove_v your_o finger_n make_v the_o vacuum_n pa._n the_o height_n of_o the_o mercurial_a standard_n will_v be_v pq_n measure_v it_o and_o if_o it_o be_v find_v equal_a to_o lk_v in_o the_o vessel_n ghi_n fig._n 4._o in_o which_o no_o air_n be_v leave_v to_o alter_v it_o it_o show_v that_o the_o cilind_a of_o quicksilver_n pq_n be_v not_o in_o the_o least_o influence_v by_o that_o little_a air_n remain_v mc_n because_o the_o space_n leave_v empty_a from_o a_o to_o p_o be_v more_o than_o sufficient_a for_o its_o utmost_a expansion_n proceed_v then_o gradual_o to_o depress_v the_o cane_n or_o shank_n bc_n into_o the_o mercury_n df_n that_o the_o level_n p_o may_v be_v gradual_o raise_v also_o suppose_v to_o r_o successive_o lessen_v the_o space_n pba_n leave_v for_o the_o air_n continue_v this_o depression_n as_o long_o as_o the_o height_n qr_n shall_v be_v find_v equal_a to_o kl_n and_o note_v that_o r_o be_v the_o fix_a and_o utmost_a bound_n of_o the_o whole_a height_n of_o a_o cilind_a of_o mercury_n equal_a to_o kl_n all_o the_o subsequent_a height_n towards_o b_o cause_v by_o a_o far_a depression_n of_o the_o cane_n into_o the_o vessel_n de_fw-fr be_v successive_o diminish_v whence_o it_o be_v probable_a that_o the_o void_a space_n abr_n be_v quite_o fill_v by_o the_o expand_v air_n because_o from_o r_o upward_o the_o mercurial_a cilind_a suffer_v some_o force_n from_o within_o a_o evident_a sign_n as_o some_o think_v that_o the_o quantity_n of_o air_n mc_n will_v not_o be_v content_v with_o a_o less_o space_n than_o abr_n for_o its_o full_a and_o free_a expansion_n the_o measure_n of_o this_o space_n abr_n and_o by_o consequence_n of_o the_o expansion_n of_o the_o air_n mc_n be_v thus_o obtain_v 3._o all_o thing_n be_v as_o in_o the_o vessel_n abc_n where_o the_o air_n mc_n have_v its_o utmost_a dilatation_n in_o the_o space_n be_v then_o seek_v the_o proportion_n between_o the_o space_n mc_n fill_v with_o air_n natural_o compress_v and_o the_o space_n be_v fill_v by_o the_o same_o air_n dilate_v which_o be_v find_v at_o one_o trial_n by_o weigh_v the_o water_n that_o may_v be_v contain_v in_o the_o space_n mc_n and_o likewise_o that_o which_o may_v be_v contain_v in_o be_v as_o suppose_v they_o be_v find_v in_o proportion_n to_o each_o other_o as_o 1_o to_o 174_o we_o may_v affirm_v the_o same_o of_o the_o air_n that_o when_o at_o its_o great_a expansion_n it_o take_v up_o 173_o time_n a_o large_a space_n than_o when_o in_o the_o state_n of_o its_o natural_a compression_n note_v that_o have_v often_o reiterated_a this_o experiment_n and_o at_o divers_a season_n it_o have_v not_o always_o succeed_v in_o the_o same_o proportion_n for_o when_o at_o first_o we_o make_v it_o with_o another_o kind_n of_o apparatus_n though_o the_o operation_n be_v much_o the_o
the_o seat_n of_o fire_n and_o that_o by_o no_o other_o than_o by_o the_o natural_a gravity_n of_o those_o humid_a part_n be_v by_o mean_n of_o the_o coalition_n with_o it_o attemper_v by_o the_o new_a acquire_v levity_n however_o this_o may_v be_v in_o confirmation_n of_o this_o opinion_n we_o will_v produce_v only_o two_o experiment_n who_o weight_n may_v perchance_o make_v up_o the_o deficiency_n of_o their_o number_n tab._n 18._o p._n 119._o the_o first_o experiment_n 1._o let_v there_o be_v a_o cilind_a of_o wood_n abc_n who_o base_a bc_n exact_o touch_v the_o horizontal_a plane_n de_fw-fr and_o that_o the_o ambient_fw-la air_n get_v between_o the_o two_o superficies_n may_v not_o hinder_v the_o trueness_n of_o their_o contact_n let_v the_o base_a of_o the_o cilind_a be_v line_v with_o a_o plate_n of_o metal_n plain_v and_o well_o polish_a and_o another_o like_a piece_n lead_v into_o the_o horizontal_a plane_n then_o make_v a_o ridge_n with_o wax_n or_o plaster_n round_o about_o the_o cilind_a pour_v mercury_n into_o the_o trench_n up_o to_o f_o that_o the_o contact_n may_v be_v every_o way_n cover_v and_o hinder_v from_o the_o ingress_n of_o the_o air_n then_o fasten_v the_o end_n of_o the_o cilind_a a_o to_o one_o of_o the_o equal_a arm_n of_o a_o beam_n gh_o who_o centre_n be_v i_o at_o the_o other_o end_n h_n hang_v the_o weight_n i_o equal_a to_o that_o of_o the_o cilind_a abc_n it_o be_v manifest_a to_o sense_n that_o to_o raise_v the_o cilind_a from_o the_o plane_n the_o weight_n l_o be_v insufficient_a but_o several_a weight_n must_v be_v add_v to_o the_o end_n h_n till_o at_o last_o suppose_v l_o and_o m_o raise_v it_o resist_v now_o with_o a_o double_a force_n that_o be_v with_o that_o of_o its_o own_o weight_n equal_a to_o l_o and_o with_o that_o of_o the_o contact_n or_o repugnance_n to_o vacuity_n or_o what_o else_o it_o may_v be_v term_v the_o superadded_a weight_n m_o must_v not_o only_o equal_a but_o exceed_v the_o power_n of_o the_o say_v 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cilind_a a_o with_o so_o much_o weight_n q_n as_o will_v sink_v it_o to_o the_o bottom_n which_o weight_n in_o our_o experiment_n be_v about_o 5_o l._n we_o conclude_v the_o force_n inquire_v to_o be_v so_o much_o next_o we_o consider_v that_o the_o resistance_n of_o the_o contact_n of_o the_o superficies_n be_v no_o more_o than_o 3_o l._n as_o be_v say_v and_o the_o force_n of_o the_o suppose_a levity_n of_o the_o cilind_a be_v find_v to_o be_v 5_o l_o wherefore_o in_o this_o case_n that_o of_o the_o levity_n be_v more_o than_o that_o of_o the_o contact_n wherefore_o again_o consider_v the_o cilind_a of_o wood_n ab_fw-la close_v down_o with_o its_o base_a bc_n to_o the_o plane_n open_v there_o be_v then_o two_o contrary_a power_n act_v viz._n that_o of_o 5_o l._n from_o the_o levity_n to_o raise_v it_o and_o that_o of_o 3_o l._n from_o the_o contact_n which_o hold_v it_o down_o now_o the_o lesser_a force_n ought_v to_o yield_v to_o the_o great_a and_o so_o the_o cilind_a be_v raise_v but_o it_o be_v not_o so_o here_o for_o the_o contact_n be_v not_o loose_v wherefore_o it_o seem_v we_o must_v conclude_v something_o beside_o levity_n buoy_v it_o up_o the_o second_o experiment_n 3._o let_v there_o be_v a_o wooden_a vessel_n abcd_v in_o the_o thickness_n of_o the_o bottom_n whereof_o a_o concave_a hemisphere_n be_v turn_v efg_n exact_o fit_v a_o ball_n of_o ivory_n h_n adapt_v to_o its_o great_a circle_n eglantine_n then_o the_o whole_a vessel_n be_v fill_v with_o mercury_n so_o that_o the_o globe_n be_v quite_o cover_v therewith_o it_o be_v manifest_a that_o the_o weight_n of_o the_o mercury_n incumbent_a upon_o the_o bottom_n of_o the_o vessel_n and_o hinder_v from_o run_v between_o the_o low_a convex_v of_o the_o ball_n and_o concave_a of_o the_o vessel_n by_o the_o closeness_n of_o the_o contact_n at_o the_o circumference_n eglantine_n be_v not_o able_a by_o descend_v thither_o to_o raise_v the_o ball_n by_o pulsion_n but_o the_o natural_a levity_n of_o the_o ivory_n if_o there_o be_v any_o such_o thing_n may_v easy_o buoy_v it_o up_o in_o the_o heavy_a ambient_fw-la of_o the_o quicksilver_n but_o this_o do_v not_o follow_v the_o ball_n remain_v unmoved_a in_o its_o socket_n under_o any_o height_n of_o mercury_n nor_o can_v it_o be_v object_v that_o nature_n avoid_v a_o vacuum_n which_o must_v follow_v upon_o the_o first_o loosen_a of_o the_o ball_n from_o the_o concave_n of_o the_o vessel_n hinder_v the_o natural_a levity_n of_o the_o ball_n from_o its_o effect_n for_o though_o we_o make_v a_o hole_n through_o the_o bottom_n of_o the_o vessel_n fi_n whereby_o the_o air_n have_v admission_n to_o fill_v the_o space_n leave_v void_a upon_o sever_a the_o ball_n yet_o for_o all_o this_o it_o be_v not_o raise_v and_o because_o it_o may_v be_v say_v that_o the_o ball_n be_v touch_v by_o the_o air_n below_o be_v not_o light_a but_o heavy_a than_o it_o we_o again_o stop_v up_o the_o hole_n and_o enlarge_v the_o socket_n as_o it_o appear_v elg_n so_o that_o only_o the_o edge_n or_o upper_a circle_n of_o the_o hole_n eglantine_n remain_v equal_a to_o the_o great_a circle_n of_o the_o ball_n but_o the_o hemisphere_n efg_n be_v not_o now_o fit_v to_o the_o concave_a elg_n as_o be_v plain_a in_o the_o figure_n we_o then_o fill_v elg_n with_o mercury_n and_o forcible_o thrust_v down_o the_o ball_n till_o its_o great_a circle_n touch_v the_o edge_n of_o the_o concave_n now_o though_o it_o be_v but_o slight_o hold_v by_o the_o circle_n eglantine_n so_o that_o with_o a_o very_a little_a force_n it_o may_v be_v turn_v about_o yet_o we_o fill_v up_o the_o vessel_n with_o mercury_n and_o it_o be_v not_o raise_v nor_o move_v 4._o last_o that_o it_o may_v not_o be_v suspect_v that_o the_o mercury_n pour_v on_o by_o press_v upon_o the_o ball_n hold_v it_o down_o with_o its_o weight_n from_o swim_v we_o take_v instead_o of_o the_o ball_n h_o a_o conical_a glass_n vessel_n abcd_v and_o fit_v a_o lesser_a circle_n thereof_o to_o the_o edge_n of_o and_o pour_v mercury_n round_o about_o it_o it_o keep_v still_o unmoved_a and_o to_o be_v satisfy_v if_o the_o suppose_a tenacious_a union_n between_o the_o glass_n and_o the_o mercury_n together_o with_o nature_n fuga_fw-la vacui_fw-la be_v able_a to_o surpass_v the_o power_n of_o the_o glass_n levity_n we_o try_v the_o force_n of_o that_o contact_n by_o take_v away_o the_o mercury_n from_o about_o the_o glass_n and_o fasten_v of_o it_o to_o the_o one_o terminus_n of_o a_o equal_a balance_n gh_o hang_v a_o weight_n i_o at_o the_o other_o h_n till_o the_o glass_n be_v loosen_v from_o the_o socket_n of_o which_o weight_n be_v with_o we_o about_o a_o pound_n than_o fill_v the_o vessel_n again_o with_o mercury_n we_o set_v the_o glass_n to_o swim_v therein_o and_o load_v it_o as_o in_o the_o other_o experiment_n till_o it_o sink_v it_o to_o the_o bottom_n and_o keep_v it_o there_o this_o weight_n which_o with_o we_o be_v about_o 2_o ½_o l._n may_v be_v the_o true_a measure_n of_o the_o momentum_fw-la believe_v to_o proceed_v from_o the_o levity_n of_o the_o glass_n abcd_v which_o be_v more_o than_o that_o whereby_o it_o resist_v a_o vacuity_n which_o be_v but_o one_o pound_n then_o if_o the_o lightness_n be_v that_o which_o cause_v the_o glass_n to_o swim_v it_o will_v have_v produce_v its_o effect_n dissolve_v the_o contact_n since_o its_o force_n be_v much_o great_a than_o that_o of_o the_o contact_n resist_v it_o but_o it_o do_v not_o do_v it_o therefore_o it_o seem_v that_o the_o same_o be_v confirm_v by_o this_o second_o experiment_n which_o be_v conclude_v from_o the_o former_a viz._n that_o it_o be_v some_o other_o cause_n beside_o the_o levity_n that_o lift_v up_o