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lecture_n and_o collection_n make_v by_o robert_n hooke_n secretary_n of_o the_o royal_a society_n cometa_fw-la contain_v observation_n of_o the_o comet_n in_o april_n 1677._o fragment_n of_o several_a lecture_n about_o those_o of_o 1664._o and_o 1665._o sir_n chr._n wren_n hypothesis_n and_o geometrical_a problem_n about_o those_o comet_n a_o discourse_n concern_v the_o comet_n of_o 1677._o mr._n boyle_n observation_n make_v on_o two_o new_a phosphori_n of_o mr._n baldwin_n and_o mr._n craft_n mr._n gallet_n letter_n to_o mr._n cassini_n together_o with_o his_o observation_n of_o ☿_o sub_fw-la ☉_o mr._n cassini_n '_o reflection_n upon_o those_o of_o gassendus_fw-la and_o hevelius_n and_o upon_o this_o mr._n hally_n letter_n and_o observation_n of_o the_o same_o make_v at_o st._n helena_n mr._n cassini_n observation_n of_o the_o diurnal_a motion_n of_o ♃_o and_o other_o change_n happen_v in_o it_o microscopium_fw-la contain_v mr._n leeuwenhoeck_n two_o letter_n concern_v some_o late_a microscopical_a discovery_n the_o author_n discourse_n and_o description_n of_o microscope_n improve_v for_o discern_v the_o nature_n and_o texture_n of_o body_n p._n cherubine_n accusation_n answer_v mr._n young_n letter_n contain_v several_a anatomical_a observation_n london_n print_v for_o j._n martin_n printer_n to_o the_o royal_a society_n at_o the_o bell_n in_o st._n paul_n churchyard_n 1678._o viro_fw-la perillustri_fw-la d_o no_o josepho_n williamson_n equiti_fw-la aurato_fw-la serenissimo_fw-la carolo_n two_o o._n mag._n britan._n fran._n &_o hibern_n regi_fw-la a_fw-la consiliis_fw-la secretioribus_fw-la et_fw-la a_o secretis_fw-la status_fw-la nec_fw-la non_fw-la societatis_fw-la regalis_fw-la londinensis_fw-la ad_fw-la scientiam_fw-la naturalem_fw-la promovendam_fw-la praesidi_fw-la dignissimo_fw-la nec_fw-la potui_fw-la nec_fw-la debui_fw-la nobilissime_fw-it vir_fw-la cujusquam_fw-la aliûs_fw-la nomen_fw-la he_o chartis_fw-la inscribere_fw-la praeter_fw-la tuum_fw-la sub_fw-la te_fw-la natae_fw-la tibi_fw-la vitam_fw-la debent_fw-la tibi_fw-la quoque_fw-la debebunt_fw-la quod_fw-la lucem_fw-la aspiciant_fw-la egregius_fw-la ille_fw-la tuus_fw-la animus_n ad_fw-la instaurandam_fw-la philosophiam_fw-la artesque_fw-la adeo_fw-la omnes_fw-la utiles_fw-la mihi_fw-la homini_fw-la alioquin_fw-la subtimido_fw-la audaciam_fw-la huius_fw-la dedicationis_fw-la fecit_fw-la ego_fw-la quae_fw-la nunc_fw-la potui_fw-la profero_fw-la magis_fw-la ad_fw-la gratulationem_fw-la ostendendam_fw-la quam_fw-la eruditionem_fw-la spero_fw-la autem_fw-la quemadmoduni_fw-la sub_fw-la tuo_fw-la praesidio_fw-la majora_fw-la indy_n augmenta_fw-la scientiarum_fw-la in_o hâc_fw-la gente_fw-la fiunt_fw-la ita_fw-la exorituros_fw-la viros_fw-la doctos_fw-la qui_fw-la tibi_fw-la justa_fw-la praeconia_fw-la laudum_fw-la persolvant_fw-la quod_fw-la ego_fw-la prae_fw-la tenuitate_fw-la ne_fw-la conari_fw-la quidem_fw-la audeo_fw-la quanquam_fw-la cum_fw-la primis_fw-la sim_fw-la dignitatis_fw-la &_o honoris_fw-la tui_fw-la studiosissimus_fw-la robertus_fw-la hooke_n synopsis_fw-la the_o comet_n see_v april_n 21._o 1677._o between_o the_o triangle_n and_o the_o cloud_n of_o ♈_o its_o tail_n not_o direct_o opposite_a to_o the_o ☉_o its_o magnitude_n brightness_n head_n nucleus_n blaze_n 1._o why_o sometime_o short_a sometime_o long_o without_o sensible_a motion_n of_o part_n explanation_n of_o the_o first_o figure_n as_o see_v by_o the_o eye_n 2._o of_o the_o second_o figure_n as_o see_v through_o a_o glass_n of_o a_o parabolic_a termination_n differ_v from_o the_o representation_n of_o mr._n hevelius_n 3._o the_o medulla_n and_o blaze_v with_o the_o manner_n of_o shorten_v and_o lengthen_v explain_v by_o the_o three_o figure_n not_o see_v the_o 22d_o but_o the_o 23d_o the_o bigness_n of_o the_o nucleus_n and_o head_n through_o a_o telescope_n compare_v with_o the_o top_n of_o a_o tower_n 4._o the_o place_n it_o then_o appear_v in_o why_o the_o motion_n be_v not_o more_o exact_o observe_v it_o be_v blaze_n still_o not_o opposite_a to_o the_o sun_n the_o 24_o not_o see_v nor_o 25_o 5._o though_o the_o sky_n clear_a by_o reason_n of_o the_o height_n of_o vapour_n how_o they_o do_v lengthen_v the_o crepusculum_fw-la why_o physical_a remark_n only_o be_v make_v 6._o publish_a in_o order_n to_o understand_v objection_n and_o propound_v pertinent_a query_n some_o observation_n note_n query_n etc._n etc._n concern_v the_o comet_n in_o 1664._o and_o 1665._o here_o collect_v out_o of_o several_a scatter_a paper_n and_o lecture_n of_o they_o former_o read_v here_o imperfect_a query_n of_o its_o substance_n magnitude_n density_n mutability_n dissolution_n fluidity_n gravity_n light_n figure_n motion_n bend_a or_o straight_o 7._o with_o equal_a or_o unequal_a velocity_n in_o the_o atmosphere_n or_o aether_n above_o or_o below_o the_o moon_n whether_o it_o waste_v or_o last_v to_o return_v the_o star_n of_o a_o compact_a light_n 8._o vary_v possible_o from_o position_n partly_o from_o real_a change_n tail_n transparent_a body_n suppose_v more_o dense_a side_n towards_o the_o sun_n even_o define_v encompass_v with_o a_o fluid_a yield_n to_o motion_n but_o dissolve_v its_o part_n it_o be_v light_a from_o its_o self_n 9_o it_o be_v nucleus_n suppose_v dense_a possible_o as_o the_o middle_a part_n of_o the_o earth_n of_o which_o some_o conjecture_n dissolve_v by_o the_o aether_n as_o in_o our_o atmosphere_n 10._o argument_n for_o the_o looseness_n of_o the_o central_a part_n of_o the_o earth_n from_o the_o variation_n of_o magnetical_a direction_n 11._o the_o nucleus_n of_o comet_n possible_o the_o same_o internal_a motion_n may_v weaken_v gravitation_n part_n separate_v may_v be_v agitate_a by_o the_o gravitation_n of_o the_o ☉_o tail_n make_v not_o so_o much_o by_o the_o particle_n recede_v as_o the_o star_n approach_v the_o sun_n 12._o how_o the_o comet_n may_v first_o lose_v its_o orb_n in_o the_o universe_n and_o pass_v through_o the_o sphere_n of_o activity_n of_o several_a central_a body_n be_v deflect_v and_o attract_v by_o they_o and_o the_o blaze_n raise_v to_o a_o prodigious_a length_n 13._o the_o body_n be_v attract_v by_o some_o gravity_n blaze_n expel_v by_o levity_n explain_v by_o smoke_n and_o steam_n somewhat_o for_o positive_a levity_n 14._o a_o digression_n concern_v the_o method_n of_o speculate_v the_o great_a and_o first_o principle_n of_o the_o universe_n the_o coma_n and_o blaze_n like_o smoke_n or_o flame_n 15._o shine_v particle_n a_o shine_a point_n not_o a_o line_n of_o light_n consideration_n and_o experiment_n about_o the_o way_n light_n be_v augment_v by_o as_o by_o swift_a motion_n adjacent_a dark_a medium_n flame_v explain_v why_o the_o particle_n coalesce_v into_o a_o stream_n 16._o enquiry_n about_o the_o magnitude_n and_o place_n of_o comet_n many_o suppose_v they_o sublunary_a tycho_n and_o kepler_n prove_v they_o celestial_a how_o far_o we_o may_v rely_v upon_o observation_n for_o parallax_n parallax_n and_o its_o effect_n describe_v 18._o tycho_n suppose_v the_o comet_n of_o 1577._o to_o move_v about_o the_o sun_n kepler_n that_o of_o 1607._o to_o move_v in_o a_o straight_a line_n that_o of_o 1664._o have_v no_o sensible_a parallax_n by_o what_o mean_v it_o be_v find_v 19_o refraction_n in_o this_o way_n vary_v little_a theory_n of_o comet_n defective_a as_o to_o parallax_n hitherto_o parallax_n not_o to_o be_v inquire_v from_o the_o observation_n of_o several_a man_n error_n creep_v in_o from_o the_o press_n and_o the_o grave_a as_o in_o p._n gottignies_n plate_n 20._o nothing_o to_o be_v conclude_v from_o observation_n make_v by_o person_n in_o differ_v place_n for_o want_n of_o accurate_a instrument_n and_o observation_n 21._o even_o the_o best_a as_o hevelius_n gottignies_n petit_n or_o auzout_v err_v some_o reason_n for_o this_o assertion_n most_o of_o the_o rest_n altogether_o insignificant_a 22._o want_v of_o observer_n instrument_n and_o table_n the_o cause_n how_o these_o want_n be_v to_o be_v supply_v what_o the_o world_n expect_v from_o mr._n hevelius_n 23._o and_o of_o how_o great_a use_v his_o table_n and_o projection_n make_v by_o they_o will_v be_v parallax_n from_o diurnal_a motion_n fail_v 24._o other_o parallax_n arise_v from_o other_o hypothesis_n of_o the_o proper_a motion_n either_o of_o the_o earth_n or_o comet_n or_o both_o together_o consider_v arise_v to_o a_o certainty_n 25._o other_o depend_v upon_o other_o supposition_n define_v nothing_o of_o the_o magnitude_n or_o distance_n of_o comet_n the_o inconvenience_n of_o tycho_n and_o also_o of_o kepler_n hypothesis_n explain_v a_o three_o way_n i_o have_v take_v what_o consequence_n follow_v from_o it_o 26._o as_o that_o it_o move_v in_o a_o circle_n that_o come_v within_o the_o earth_n orb_n in_o ♌_o and_o without_o ♃_o orb_n in_fw-it ♒_o a_o sextant_a in_o 130_o day_n etc._n etc._n this_n not_o rely_v on_o because_o there_o may_v be_v other_o hypothesis_n to_o solve_v the_o phaenomena_fw-la as_o that_o the_o earth_n be_v unmoved_a and_o the_o comet_n move_v in_o a_o circle_n who_o convex_a side_n be_v towards_o the_o earth_n 27._o this_o hypothesis_n explain_v by_o the_o six_o figure_n 28._o the_o distance_n and_o bigness_n of_o the_o circle_n of_o the_o comet_n undeterminable_a this_o way_n without_o a_o diurnal_a parallax_n
plain_o observe_v a_o perfect_a representation_n of_o the_o head_n halo_n and_o beard_n of_o the_o comet_n for_o the_o menstruum_fw-la fall_v on_o or_o dissolve_v the_o iron_n there_o be_v a_o continual_a eruption_n of_o small_a bubble_n and_o dissolve_v particle_n from_o all_o the_o side_n of_o this_o body_n and_o after_o the_o eruption_n they_o all_o ascend_v upward_o from_o the_o centre_n of_o the_o earth_n for_o be_v of_o a_o much_o light_a consistence_n than_o the_o anbient_a liquor_n they_o be_v by_o the_o great_a gravity_n of_o that_o continual_o protrude_v upward_o the_o same_o appearance_n may_v be_v make_v with_o any_o kind_n of_o menstruum_fw-la and_o a_o convenient_a dissoluble_a body_n suspend_v in_o it_o so_o that_o if_o we_o suppose_v the_o aether_n to_o be_v somewhat_o analogous_a to_o a_o menstruum_fw-la and_o that_o there_o be_v a_o gravitation_n towards_o the_o centre_n of_o the_o sun_n if_o the_o nucleus_n or_o head_n of_o the_o comet_n be_v suppose_v such_o a_o 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and_o may_v likewise_o hereafter_o appear_v again_o that_o it_o be_v probable_a the_o near_a distance_n of_o it_o be_v much_o great_a than_o that_o of_o the_o moon_n that_o the_o length_n of_o its_o beard_n be_v long_o than_o its_o distance_n from_o the_o earth_n and_o consequent_o several_a time_n long_o than_o the_o distance_n between_o the_o earth_n and_o the_o moon_n that_o its_o visible_a way_n among_o the_o star_n be_v very_o differ_v from_o a_o great_a circle_n especial_o towards_o the_o latter_a end_n when_o it_o become_v retrograde_a that_o its_o way_n through_o the_o aether_n can_v not_o be_v suppose_v equal_a in_o a_o straight_a line_n though_o it_o may_v be_v suppose_v equal_a in_o a_o curve_v or_o circle_n that_o the_o exact_a way_n of_o it_o can_v not_o be_v certain_o determine_v by_o the_o best_a observation_n i_o have_v yet_o meet_v with_o and_o that_o therefore_o the_o best_a help_n we_o have_v to_o guess_v of_o its_o way_n and_o distance_n be_v by_o its_o manner_n of_o move_v as_o to_z appearance_n among_o the_o fix_a star_n which_o i_o have_v already_o show_v to_o be_v explicable_a by_o various_a hypothesis_n for_o both_o the_o earth_n and_o comet_n may_v be_v suppose_v to_o be_v move_v either_o both_o one_o way_n or_o contrary_a way_n or_o cross_a way_n the_o earth_n may_v be_v suppose_v to_o stand_v still_o and_o the_o comet_n only_o to_o be_v move_v and_o the_o like_a these_o requisite_n therefore_o be_v hitherto_o want_v in_o the_o observation_n i_o have_v meet_v with_o of_o this_o comet_n all_o that_o can_v be_v say_v of_o it_o will_v at_o best_a be_v but_o conjectural_a and_o hypothetical_a since_o nothing_o can_v be_v reasonable_o build_v upon_o those_o observation_n where_o the_o truth_n of_o they_o be_v dubious_a want_v therefore_o sound_a material_n to_o work_v upon_o in_o this_o comet_n i_o have_v recourse_n to_o the_o observation_n of_o the_o noble_a dane_n tycho_n brahe_n be_v sufficient_o satisfy_v both_o of_o the_o ability_n industry_n and_o veracity_n of_o that_o excellent_a author_n who_o leave_v nothing_o unattempted_a for_o the_o perfect_a of_o such_o observation_n as_o seem_v to_o he_o requisite_a for_o the_o complete_n a_o history_n of_o that_o comet_n which_o appear_v in_o 1577._o and_o from_o those_o observation_n of_o his_o i_o endeavour_v to_o trace_v the_o way_n of_o it_o according_a to_o several_a hypothesis_n and_o find_v that_o suppose_v the_o earth_n not_o to_o be_v move_v with_o a_o annual_a motion_n but_o only_o a_o diurnal_a about_o its_o own_o axis_n the_o way_n of_o comet_n will_v fall_v in_o a_o line_n very_o near_o approach_v the_o nature_n of_o a_o circle_n though_o neither_o into_o a_o exact_a circle_n nor_o a_o exact_a ellipse_n and_o therefore_o seem_v irregular_a and_o not_o at_o all_o probable_a again_o suppose_v it_o move_v
move_v in_o a_o circle_n or_o be_v carry_v clear_a away_o and_o never_o appear_v again_o be_v move_v in_o a_o straight_a or_o paraboloeidical_a line_n whether_o it_o be_v collect_v or_o generate_v when_o it_o first_o appear_v and_o dissipate_v or_o destroy_v when_o it_o disappear_v or_o whether_o the_o several_a distance_n of_o it_o do_v not_o make_v that_o appearance_n whether_o it_o may_v not_o have_v some_o such_o propriety_n as_o the_o star_n in_o cete_fw-la whereby_o it_o may_v shine_v and_o appear_v for_o a_o certain_a period_n and_o again_o lose_v its_o light_n and_o disappear_z by_o several_a vicissitude_n and_o whether_o that_o may_v not_o give_v some_o account_n of_o the_o appearance_n of_o so_o many_o comet_n about_o aries_n first_o as_o concern_v the_o matter_n or_o substance_n of_o the_o nucleus_n star_n or_o body_n of_o the_o hazy_a shine_a part_n encompass_v it_o and_o of_o the_o tail_n or_o blaze_n i_o say_v that_o by_o compare_v all_o the_o circumstance_n that_o i_o be_v able_a to_o take_v notice_n of_o from_o the_o begin_n to_o the_o end_n i_o find_v that_o the_o star_n in_o the_o head_n be_v of_o a_o very_a compact_a and_o dense_a light_n and_o almost_o equal_v that_o of_o saturn_n though_o it_o be_v not_o like_o that_o confine_v by_o a_o equal_a limb_n that_o there_o be_v some_o part_n distinguishable_a in_o this_o body_n some_o have_v a_o bright_a other_o a_o faint_a light_n that_o these_o part_n do_v not_o continue_v the_o same_o but_o considerable_o vary_v which_o may_v in_o part_n be_v cause_v by_o the_o differ_a position_n of_o those_o part_n which_o be_v see_v before_o from_o the_o same_o see_v afterward_o in_o respect_n of_o the_o eye_n situate_v on_o the_o surface_n of_o the_o earth_n move_v one_o way_n and_o the_o comet_n move_v another_o though_o i_o do_v not_o conceive_v it_o whole_o ascribable_a to_o that_o but_o partly_o also_o to_o a_o real_a alteration_n of_o the_o part_n of_o the_o comet_n that_o i_o do_v very_o diligent_o watch_v to_o observe_v if_o it_o be_v possible_a when_o it_o pass_v over_o any_o fix_a star_n to_o find_v whether_o it_o be_v transparent_a as_o i_o have_v several_a time_n observe_v the_o tail_n of_o it_o to_o be_v even_o in_o its_o bright_a part_n but_o i_o have_v not_o the_o opportunity_n but_o that_o i_o do_v several_a time_n observe_v the_o tail_n of_o it_o transparent_a not_o only_o with_o the_o naked_a eye_n but_o through_o a_o telescope_n if_o at_o least_o the_o fix_a star_n be_v above_o it_o which_o i_o think_v few_o doubt_n that_o the_o light_n diminish_v by_o degree_n towards_o the_o extreme_n of_o the_o hazy_a part_n encompass_v it_o and_o yet_o the_o extreme_n of_o it_o as_o to_o that_o part_n of_o it_o which_o respect_v the_o sun_n seem_v pretty_a even_o and_o smooth_o define_v especial_o through_o a_o telescope_n from_o all_o which_o remark_n and_o from_o the_o velocity_n of_o its_o motion_n i_o conjecture_v it_o to_o be_v make_v up_o of_o solid_a matter_n not_o fluid_a that_o the_o body_n of_o it_o especial_o be_v considerable_o dense_a but_o that_o the_o haziness_n or_o coma_n about_o it_o be_v much_o more_o rarify_v and_o the_o tail_n thereof_o be_v most_o of_o all_o that_o this_o body_n be_v encompass_v with_o a_o body_n most_o fluid_a and_o easy_o permeable_a and_o which_o do_v with_o very_o little_a resistance_n give_v way_n to_o the_o motion_n of_o it_o or_o any_o other_o body_n through_o it_o that_o it_o do_v easy_o admit_v at_o least_o if_o not_o actual_o take_v into_o itself_o the_o part_n of_o this_o body_n coma_o and_o blaze_n i_o say_v admit_v at_o least_o though_o there_o may_v be_v many_o reason_n allege_v that_o it_o do_v actual_o prey_v upon_o and_o dissolve_v those_o part_n into_o itself_o as_o i_o shall_v show_v by_o and_o by_o because_o that_o we_o find_v that_o the_o extreme_a part_n do_v extend_v but_o to_o such_o a_o distance_n and_o beyond_o that_o there_o be_v no_o appearance_n of_o light_n and_o that_o the_o light_n be_v from_o itself_o and_o not_o produce_v by_o refraction_n or_o reflection_n of_o the_o beam_n of_o the_o sun_n i_o shall_v show_v reason_n by_o and_o by_o and_o consequent_o where_o there_o be_v most_o light_a appear_v there_o be_v the_o great_a number_n and_o there_o be_v the_o great_a density_n of_o the_o cometical_a part_n the_o middle_n of_o the_o body_n may_v be_v as_o dense_a as_o the_o body_n of_o the_o earth_n and_o i_o have_v not_o observe_v myself_o nor_o meet_v with_o any_o body_n else_o that_o have_v take_v notice_n of_o any_o thing_n to_o the_o contrary_a if_o i_o can_v have_v see_v any_o comet_n to_o have_v cover_v any_o star_n in_o its_o way_n it_o will_v have_v afford_v a_o very_a circumstantial_a information_n especial_o if_o for_o this_o purpose_n it_o have_v be_v take_v notice_n of_o with_o a_o good_a telescope_n what_o the_o density_n of_o the_o innermost_a part_n of_o this_o earth_n we_o live_v on_o be_v none_o know_v for_o though_o we_o find_v the_o part_n on_o which_o we_o tread_v to_o be_v very_o compact_a and_o though_o by_o the_o industry_n of_o miner_n it_o have_v be_v prove_v so_o also_o to_o the_o depth_n of_o many_o hundred_o foot_n as_o georgius_n agrieola_n relate_v and_o though_o it_o have_v be_v find_v so_o even_o to_o a_o great_a depth_n by_o the_o sounding_n of_o the_o bottom_n of_o the_o sea_n yet_o none_o can_v bring_v a_o undeniable_a proof_n that_o the_o same_o be_v so_o solid_a to_o 25_o mile_n deep_a much_o less_o that_o it_o be_v so_o to_o the_o centre_n if_o therefore_o the_o external_a shell_n of_o this_o globe_n be_v break_v and_o remove_v it_o be_v not_o impossible_a but_o that_o the_o middle_a part_n thereof_o may_v be_v of_o the_o same_o nature_n with_o the_o middle_a part_n of_o the_o comet_n body_n and_o that_o those_o part_n be_v the_o superficial_a part_n or_o shell_n remove_v may_v like_o these_o of_o comet_n expand_v themselves_o into_o the_o encompass_v aether_n nay_o we_o find_v that_o notwithstanding_o the_o compactedness_n of_o the_o superficial_a part_n of_o this_o earth_n yet_o the_o aether_n be_v able_a to_o take_v up_o into_o itself_o vast_a quantity_n of_o they_o and_o to_o keep_v they_o suspend_v some_o of_o they_o even_o to_o the_o height_n of_o many_o mile_n if_o any_o argument_n may_v be_v draw_v from_o the_o height_n or_o length_n of_o the_o dawn_a oâ—_n 〈◊〉_d and_o this_o notwithstanding_o the_o attraction_n of_o the_o earth_n in_o its_o perfect_a vigour_n or_o the_o gravitation_n of_o these_o part_n thus_o take_v up_o or_o their_o endeavour_n towards_o the_o centre_n of_o the_o earth_n how_o much_o more_o free_o then_o may_v we_o imagine_v the_o encompass_v aether_n to_o prey_n upon_o and_o take_v up_o into_o itself_o the_o internal_a part_n if_o they_o be_v of_o a_o loose_a and_o pervious_a texture_n and_o almost_o in_o a_o state_n of_o fluidity_n like_o a_o heap_n of_o sand_n or_o a_o vessel_n of_o alabaster-dust_n in_o boil_v and_o be_v not_o so_o firm_o unite_v by_o the_o bond_n of_o gravity_n and_o the_o vinculum_fw-la of_o petrifaction_n as_o we_o find_v the_o superficial_a part_n of_o the_o earth_n now_o be_v there_o be_v one_o argument_n to_o prove_v to_o we_o that_o there_o may_v be_v such_o a_o looseness_n of_o the_o internal_a part_n of_o the_o earth_n and_o that_o be_v that_o the_o magnetical_a virtue_n vary_v which_o virtue_n without_o controversy_n diffuse_v through_o the_o whole_a body_n of_o the_o earth_n and_o which_o have_v a_o relation_n to_o the_o whole_a globe_n and_o to_o every_o magnetical_a part_n thereof_o for_o by_o observation_n it_o be_v find_v that_o the_o magnetical_a virtue_n act_n upon_o a_o needle_n without_o it_o as_o the_o magnetical_a virtue_n of_o a_o round_a loadstone_n do_v on_o a_o needle_n apply_v without_o that_o which_o as_o i_o may_v elsewhere_o show_v have_v a_o respect_n to_o the_o centre_n of_o the_o stone_n differ_v from_o all_o the_o respect_n that_o author_n have_v hitherto_o ascribe_v to_o it_o even_o of_o gilbert_n kepler_n kircher_n descartes_n and_o our_o countryman_n mr._n bond_n who_o i_o think_v be_v the_o first_o man_n that_o endeavour_v to_o reduce_v the_o variation_n observe_v by_o wright_n gellibrand_n coster_n etc._n etc._n into_o a_o theory_n and_o calculation_n now_o this_o magnetical_a virtue_n which_o may_v be_v call_v one_o emanation_n of_o the_o anima_fw-la mundi_fw-la as_o gravity_n may_v be_v call_v another_o be_v diffuse_v through_o every_o part_n of_o it_o and_o seem_v to_o be_v as_o it_o be_v tota_n in_o toto_fw-la &_o tota_fw-la in_o qualibet_fw-la parte_fw-la and_o to_o be_v more_o spiritual_a and_o to_o act_v more_o according_a to_o magical_a and_o mystical_a law_n than_o light_n sound_z or_o the_o like_a it_o give_v to_o every_o magnetical_a body_n and_o
second_o the_o parallax_n of_o its_o proper_a motion_n compare_v with_o the_o periodick_n or_o annual_a motion_n of_o the_o earth_n the_o first_o of_o these_o may_v be_v observe_v two_o way_n either_o by_o two_o observer_n at_o part_n of_o the_o earth_n very_o far_o distant_a from_o each_o other_o but_o as_o near_o as_o may_v be_v under_o the_o same_o meridian_n as_o suppose_v the_o one_o in_o london_n the_o other_o in_o st._n helen_n both_o conspire_v in_o their_o observe_n of_o the_o place_n of_o the_o comet_n among_o the_o fix_a star_n at_o the_o same_o time_n or_o second_o by_o one_o observer_n in_o the_o same_o place_n by_o observe_v the_o place_n of_o it_o among_o the_o fix_a star_n in_o its_o rise_n or_o set_v and_o in_o a_o great_a or_o if_o it_o may_v be_v its_o great_a height_n the_o noble_a tycho_n by_o very_o accurate_a observation_n of_o the_o parallax_n prove_v the_o comet_n of_o 1577._o to_o be_v above_o the_o moon_n kepler_n by_o his_o own_o observation_n prove_v that_o of_o 1607._o at_o its_o beginning_n to_o be_v four_o time_n far_o distant_a and_o i_o doubt_v not_o but_o some_o may_v have_v be_v above_o forty_o time_n far_o but_o i_o do_v not_o yet_o find_v that_o any_o observation_n have_v accurate_o determine_v that_o which_o be_v indeed_o the_o great_a help_n by_o which_o we_o be_v enable_v to_o judge_v of_o the_o nature_n and_o all_o the_o other_o accident_n and_o propriety_n of_o comet_n the_o aristotelian_a philosophy_n for_o a_o long_a time_n prevail_v make_v the_o world_n believe_v they_o to_o be_v nothing_o but_o exhalation_n from_o the_o earth_n draw_v up_o into_o the_o high_a region_n of_o the_o air._n but_o tycho_n by_o his_o observation_n of_o their_o parallax_n raise_v they_o out_o of_o that_o confinement_n but_o yet_o he_o seem_v to_o place_v they_o in_o a_o orb_n about_o the_o sun_n but_o kepler_n free_v they_o from_o that_o confinement_n and_o assign_v they_o the_o universe_n to_o expatiate_v in_o but_o none_o of_o all_o these_o do_v accurate_o prove_v the_o true_a distance_n of_o they_o their_o parallax_n be_v for_o the_o most_o part_n so_o very_o small_a that_o i_o fear_v instrument_n with_o common_a light_n will_v hardly_o reach_v they_o but_o we_o must_v expect_v from_o future_a observation_n make_v with_o telescopical_a instrument_n to_o receive_v a_o certain_a answer_n to_o this_o query_n certain_a i_o be_o that_o the_o comet_n which_o begin_v to_o appear_v in_o november_n 1664._o and_o disappear_v in_o march_n follow_v be_v far_o remove_v beyond_o the_o distance_n assign_v by_o kepler_n for_o by_o my_o own_o observation_n divers_a time_n repeat_v i_o can_v not_o find_v any_o sensible_a parallax_n though_o i_o endeavour_v by_o a_o new_a method_n to_o make_v my_o observation_n more_o accurate_a now_o though_o i_o have_v not_o the_o convenience_n of_o make_v use_n of_o a_o quadrant_n or_o any_o such_o instrument_n to_o observe_v its_o place_n when_o near_o the_o horizon_n yet_o the_o way_n i_o take_v will_v i_o think_v be_v as_o good_a which_o be_v this_o with_o a_o very_a good_a six_o foot_n perspective-glass_n or_o telescope_n i_o observe_v the_o place_n of_o the_o comet_n in_o respect_n of_o the_o adjacent_a small_a star_n as_o soon_o as_o it_o appear_v and_o so_o trace_v its_o way_n till_o it_o disappear_v in_o the_o vapour_n of_o the_o horizon_n the_o like_a i_o do_v several_a other_o day_n successive_o take_v notice_n by_o what_o degree_n in_o what_o time_n it_o make_v its_o progress_n to_o see_v whether_o by_o its_o parallax_n when_o near_o the_o horizon_n it_o will_v have_v be_v depress_v below_o that_o line_n of_o its_o motion_n which_o it_o keep_v when_o at_o a_o great_a height_n above_o it_o but_o though_o i_o try_v this_o several_a time_n yet_o i_o be_v not_o able_a to_o discern_v that_o the_o parallax_n of_o it_o cause_v either_o any_o sensible_a bend_n of_o the_o line_n or_o any_o sensible_a inequality_n in_o its_o progress_n by_o which_o i_o shall_v have_v soon_o find_v it_o than_o by_o take_v its_o altitude_n with_o common_a instrument_n though_o i_o confess_v these_o observation_n be_v make_v when_o the_o motion_n of_o the_o comet_n be_v slow_a and_o consequent_o when_o in_o probability_n it_o be_v far_o distant_a from_o the_o earth_n to_o i_o there_o seem_v no_o doubt_n but_o that_o it_o be_v a_o long_a way_n remove_v above_o the_o moon_n when_o i_o make_v these_o observation_n for_o have_v it_o be_v of_o a_o equal_a distance_n with_o that_o they_o allow_v the_o moon_n it_o must_v this_o way_n have_v manifest_v a_o very_a sensible_a parallax_n of_o divers_a minute_n but_o whereas_o i_o can_v not_o certain_o distinguish_v any_o sensible_a at_o all_o it_o must_v be_v many_o time_n high_o than_o the_o moon_n now_o that_o this_o way_n be_v abundant_o to_o be_v prefer_v before_o a_o observation_n make_v with_o a_o quadrant_n for_o the_o take_n of_o its_o altitude_n be_v pretty_a evident_a because_o by_o this_o mean_v the_o great_a part_n of_o the_o irregularity_n cause_v by_o the_o refraction_n or_o inflection_n of_o the_o air_n be_v remove_v for_o by_o this_o mean_n though_o the_o parallax_n be_v very_o large_a yet_o the_o refraction_n or_o inflection_n of_o the_o air_n will_v not_o amount_v to_o many_o second_o both_o the_o object_n be_v almost_o equal_o raise_v by_o refraction_n especial_o when_o 5_o or_o 10_o degree_n high_a near_o than_o which_o the_o small_a star_n vanish_v out_o of_o sight_n by_o the_o thickness_n of_o our_o air_n it_o follow_v therefore_o that_o a_o semidiameter_n of_o the_o earth_n must_v be_v a_o very_a inconsiderable_a measure_n in_o its_o distance_n this_o part_n therefore_o of_o the_o theory_n of_o comet_n have_v be_v much_o defective_a hitherto_o if_o we_o inquire_v the_o parallax_n of_o they_o from_o the_o observation_n of_o divers_a man_n make_v in_o differ_v place_n we_o shall_v find_v they_o so_o differ_v one_o from_o another_o that_o there_o be_v great_a reason_n to_o suspect_v they_o all_o nay_o not_o only_o so_o but_o in_o this_o comet_n of_o 1664._o by_o compare_v two_o table_n or_o chart_n of_o the_o star_n and_o constellation_n of_o that_o part_n of_o the_o heaven_n through_o which_o the_o comet_n past_a on_o which_o be_v also_o mark_v out_o its_o way_n and_o place_n from_o day_n to_o day_n both_o of_o they_o print_v from_o copper_n plate_n i_o find_v that_o strange_a error_n and_o mistake_n may_v be_v create_v notwithstanding_o all_o the_o author_n care_n and_o accurateness_n possible_a from_o the_o carelessness_n or_o neglect_n of_o the_o grave_a this_o i_o note_v in_o the_o two_o table_n of_o the_o learned_a and_o accurate_a mathematician_n p._n aegidius_n franciscus_n de_fw-fr gotignies_n who_o skill_n and_o care_n from_o other_o work_n of_o he_o and_o other_o observation_n of_o this_o comet_n i_o be_o sufficient_o assure_v of_o and_o find_v that_o by_o the_o first_o table_n upon_o the_o 21_o 31_o of_o december_n 1664._o it_o be_v in_o 4½_n of_o ♊_o in_o longitude_n and_o in_o 33⅔_n of_o southern_a latitude_n but_o by_o the_o second_o it_o be_v place_v at_o the_o same_o time_n in_o 4_o o_o ♊_o for_o its_o longitude_n and_o in_o 34½_n of_o south_n latitude_n and_o this_o error_n be_v not_o only_o commit_v in_o the_o place_n of_o the_o comet_n but_o also_o in_o the_o place_n of_o the_o fix_a star_n for_o riget_fw-la in_o the_o first_o table_n be_v place_v in_o 30¾_n south_n latitude_n and_o in_o 12¼_n ♊_o for_o longitude_n but_o in_o the_o second_o in_o 31½_n south_n latitude_n and_o in_o 11½_n ♊_o for_o longitude_n both_o which_o differ_v considerable_o from_o the_o place_n of_o it_o assign_v by_o riccioli_n and_o grimaldi_n according_a to_o who_o observation_n it_o shall_v be_v in_o 31._o 11′_n south_n latitude_n and_o 12°_n 11′_n 40″_n ♊_o in_o longitude_n now_o if_o there_o be_v these_o difference_n to_o be_v remark_v in_o the_o observation_n of_o one_o we_o can_v but_o expect_v that_o much_o more_o disagreement_n shall_v be_v find_v between_o those_o which_o have_v be_v make_v by_o differ_v person_n in_o differ_v place_n and_o with_o differ_v way_n and_o differ_v instrument_n and_o upon_o examination_n i_o have_v find_v it_o no_o better_o for_o from_o compare_v such_o observation_n as_o i_o have_v receive_v from_o several_a part_n of_o the_o world_n even_o of_o those_o which_o have_v seem_v more_o than_o ordinary_o exact_a i_o find_v they_o for_o the_o most_o part_n so_o unaccurate_a that_o though_o they_o sufficient_o manifest_v that_o the_o comet_n of_o 1664._o which_o last_v above_o four_o month_n be_v visible_a in_o most_o part_n of_o the_o world_n and_o see_v to_o pass_v in_o all_o those_o place_n pretty_a near_o in_o the_o same_o way_n among_o the_o fix_a star_n yet_o they_o be_v so_o far_o from_o manifest_v the_o parallax_n that_o
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