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that_o i_o shall_v prove_v be_v that_o the_o gradual_a heat_n and_o cool_v of_o these_o so_o extend_a body_n do_v reduce_v the_o part_n of_o the_o glass_n to_o a_o loose_a and_o soft_a temper_n and_o this_o i_o find_v by_o heat_a they_o and_o keep_v they_o for_o a_o pretty_a while_n very_o red_a hot_a in_o a_o fire_n for_o thereby_o i_o find_v they_o to_o grow_v a_o little_o light_a and_o the_o small_a stem_n to_o be_v very_o easy_o break_v and_o snap_v any_o where_o without_o at_o all_o make_v the_o drop_n fly_v whereas_o before_o they_o be_v so_o exceed_o hard_a that_o they_o can_v not_o be_v break_v without_o much_o difficulty_n and_o upon_o their_o break_v the_o whole_a drop_n will_v fly_v in_o piece_n with_o very_o great_a violence_n the_o reason_n of_o which_o last_o seem_v to_o be_v that_o the_o leisurely_o heat_n and_o cool_v of_o the_o part_n do_v not_o only_o waste_v some_o part_n of_o the_o glass_n itself_o but_o range_v all_o the_o part_n into_o a_o better_a order_n and_o 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hot_a which_o notwithstanding_o fall_v upon_o the_o tinder_n that_o be_v only_o a_o very_a curious_a small_a coal_n make_v of_o the_o small_a thread_n of_o linen_n burn_v to_o coal_n and_o charge_v it_o easy_o set_v it_o on_o fire_n nor_o will_v any_o part_n of_o this_o hypothesis_n seem_v strange_a to_o he_o that_o consider_v first_o that_o either_o hammer_v or_o file_v or_o otherwise_o violent_o rub_v of_o steel_n will_v present_o make_v it_o so_o hot_a as_o to_o be_v able_a to_o burn_v one_o finger_n next_o that_o the_o whole_a force_n of_o the_o stroke_n be_v exert_v upon_o that_o small_a part_n where_o the_o flint_n and_o steel_n first_o touch_n for_o the_o body_n be_v each_o of_o they_o so_o very_o hard_o the_o pull_v can_v be_v far_o communicate_v that_o be_v the_o part_n of_o each_o can_v yield_v but_o very_o little_a and_o therefore_o the_o violence_n of_o the_o concussion_n will_v be_v exert_v on_o that_o piece_n of_o steel_n which_o be_v cut_v off_o by_o the_o flint_n three_o that_o the_o file_n or_o small_a part_n of_o steel_n be_v very_o apt_a as_o it_o be_v to_o take_v fire_n and_o be_v present_o red_a hot_a that_o be_v there_o seem_v to_o be_v a_o very_a combustible_a sulphureous_a body_n in_o iron_n or_o steel_n which_o the_o air_n very_o ready_o prey_v upon_o as_o soon_o as_o the_o body_n be_v a_o little_a violent_o heat_v and_o this_o be_v obvious_a in_o the_o file_n of_o steel_n or_o iron_n cast_v through_o the_o flame_n of_o a_o candle_n for_o even_o by_o that_o sudden_a transitus_fw-la of_o the_o small_a chip_n of_o iron_n they_o be_v heat_n red_a hot_a and_o that_o combustible_a sulphureous_a body_n be_v present_o prey_v upon_o and_o devour_v by_o the_o aereal_a encompass_v menstruum_fw-la who_o office_n in_o this_o particular_a i_o have_v show_v in_o the_o explication_n of_o charcoal_n and_o in_o prosecution_n of_o this_o experiment_n have_v take_v the_o file_n of_o iron_n and_o steel_n and_o with_o the_o point_n of_o a_o knife_n cast_v 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business_n of_o its_o harden_v and_o temper_v of_o which_o somewhat_o be_v say_v in_o the_o description_n of_o muscovy-glass_n so_o that_o these_o thing_n consider_v we_o need_v not_o trouble_v ourselves_o to_o find_v out_o what_o kind_n of_o pore_n they_o be_v both_o in_o the_o flint_n and_o steel_n that_o contain_v the_o atom_n of_o fire_n nor_o how_o those_o atom_n come_v to_o be_v hinder_v from_o run_v all_o out_o when_o a_o door_n or_o passage_n in_o their_o pore_n be_v make_v by_o the_o concussion_n nor_o need_v we_o trouble_v ourselves_o to_o examine_v by_o what_o prometheus_n the_o element_n of_o fire_n come_v to_o be_v fetch_v down_o from_o above_o the_o region_n of_o the_o air_n in_o what_o cell_n or_o box_n it_o be_v keep_v and_o what_o epimetheus_n let_v it_o go_v nor_o to_o consider_v what_o it_o be_v that_o cause_n so_o great_a a_o conflux_n of_o the_o atomical_a particle_n of_o fire_n which_o be_v say_v to_o fly_v to_o a_o flame_a body_n like_o vulture_n or_o eagle_n to_o a_o putrify_a carcase_n and_o there_o to_o make_v a_o very_a great_a pother_n since_o we_o have_v nothing_o more_o difficult_a in_o this_o hypothesis_n to_o conceive_v first_o as_o to_o the_o kindle_v of_o tinder_n then_o how_o a_o large_a iron-bullet_n let_v fall_v red_a or_o glow_a hot_a upon_o a_o heap_n of_o small-coal_n shall_v set_v fire_n to_o those_o that_o be_v next_o to_o it_o first_o nor_o second_o be_v this_o last_o more_o difficult_a to_o be_v explicate_v then_o that_o a_o body_n as_o silver_n for_o instance_n put_v into_o a_o weak_a menstruum_fw-la as_o unrectify_v aqua_fw-la fortis_fw-la shall_v when_o it_o be_v put_v in_o a_o great_a heat_n be_v there_o dissolve_v by_o it_o and_o not_o before_o which_o
agitate_v and_o rarify_n the_o waterish_a transparent_a and_o volatile_a water_n that_o be_v contain_v in_o they_o by_o the_o continuation_n of_o that_o action_n do_v so_o total_o expel_v and_o drive_v away_o all_o that_o which_o before_o fill_v the_o pore_n and_o be_v disperse_v also_o through_o the_o solid_a mass_n of_o it_o and_o thereby_o cause_v a_o universal_a kind_n of_o transparency_n that_o it_o not_o only_o leave_v all_o the_o pore_n empty_a but_o all_o the_o interstitia_fw-la also_o so_o dry_a and_o opacous_a and_o perhaps_o also_o yet_o further_o persorate_v that_o that_o light_n only_o be_v reflect_v back_o which_o fall_v upon_o the_o very_a outward_a edge_n of_o the_o pore_n all_o they_o that_o enter_v into_o the_o pore_n of_o the_o body_n never_o return_v but_o be_v lose_v in_o it_o now_o that_o the_o char_a or_o coal_v of_o a_o body_n be_v nothing_o else_o may_v be_v easy_o believe_v by_o one_o that_o shall_v consider_v the_o mean_n of_o its_o production_n which_o may_v be_v do_v after_o this_o or_o any_o such_o manner_n the_o body_n to_o be_v char_v or_o coal_v may_v be_v put_v into_o a_o cracible_a pot_n or_o any_o other_o vessel_n that_o will_v endure_v to_o be_v make_v red-hot_a in_o the_o fire_n without_o break_v and_o then_o cover_v over_o with_o sand_n so_o as_o no_o part_n of_o it_o be_v suffer_v to_o be_v open_a to_o the_o air_n then_o set_v into_o a_o good_a fire_n and_o there_o keep_v till_o the_o sand_n have_v continue_v red_a hot_a for_o a_o quarter_n half_a a_o hour_n or_o two_o or_o more_o according_a to_o the_o nature_n and_o bigness_n of_o the_o body_n to_o be_v coal_v or_o char_v then_o take_v it_o out_o of_o the_o fire_n and_o let_v it_o stand_v till_o it_o be_v quite_o cold_a the_o body_n may_v be_v take_v out_o of_o the_o sand_n well_o char_v and_o cleanse_v of_o its_o waterish_a part_n but_o in_o the_o take_n of_o it_o out_o care_n must_v be_v have_v that_o the_o sand_n be_v very_o near_o cold_a for_o else_o when_o it_o come_v 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learn_v what_o part_n of_o the_o wood_n it_o be_v that_o be_v the_o combustible_a matter_n for_o since_o we_o shall_v find_v that_o none_o or_o very_o little_a of_o those_o fluid_a substance_n that_o be_v drive_v over_o into_o the_o receiver_n be_v combustible_a and_o that_o most_o of_o that_o which_o be_v leave_v behind_o be_v so_o it_o follow_v that_o the_o solid_a interstitia_fw-la of_o the_o wood_n be_v the_o combustible_a matter_n further_o the_o reason_n why_o uncharred_a wood_n burn_v with_o a_o great_a flame_n than_o that_o which_o be_v char_v be_v as_o evident_a because_o those_o waterish_a or_o volatile_a part_n issue_v out_o of_o the_o fire_a wood_n every_o way_n not_o only_o shatter_v and_o open_v the_o body_n the_o better_a for_o the_o fire_n to_o enter_v but_o issue_v out_o in_o vapour_n or_o wind_n they_o become_v like_o so_o many_o little_a aeolipile_n or_o bellows_o whereby_o they_o blow_v and_o agitate_v the_o fire_a part_n and_o conduce_v to_o the_o more_o speedy_a and_o violent_a consumption_n or_o dissolution_n of_o the_o body_n three_o from_o the_o experiment_n of_o char_v of_o coal_n whereby_o we_o see_v that_o notwithstanding_o the_o great_a heat_n and_o the_o duration_n of_o it_o the_o solid_a part_n of_o the_o wood_n remain_v while_o they_o be_v preserve_v from_o the_o free_a access_n of_o the_o air_n undissipate_v we_o may_v learn_v that_o which_o have_v not_o that_o i_o know_v of_o be_v publish_v or_o hint_v nay_o not_o so_o much_o as_o think_v of_o by_o any_o and_o that_o in_o short_a be_v this_o first_o that_o the_o air_n in_o which_o we_o live_v move_v and_o breath_n and_o which_o encompass_n very_o many_o and_o cherish_v most_o body_n it_o encompass_n that_o this_o air_n be_v the_o menstruum_fw-la or_o universal_a dissolvent_a of_o all_o sulphureous_a body_n second_o that_o this_o action_n it_o perform_v not_o till_o the_o body_n be_v first_o sufficient_o heat_v as_o we_o find_v requisite_a also_o to_o the_o dissolution_n of_o many_o other_o body_n by_o several_a other_o menstruum_n three_o that_o this_o action_n of_o dissolution_n produce_v or_o generate_v a_o very_a great_a heat_n and_o that_o which_o we_o call_v fire_n and_o this_o be_v common_a also_o to_o many_o dissolution_n of_o other_o body_n make_v by_o menstruum_n of_o which_o i_o can_v give_v multitude_n of_o instance_n four_o that_o this_o action_n be_v perform_v with_o so_o great_a a_o violence_n and_o do_v so_o minutely_o act_v and_o rapid_o agitate_v the_o small_a part_n of_o the_o combustible_a matter_n that_o it_o produce_v in_o the_o diaphanous_a medium_n of_o the_o air_n the_o action_n or_o pulse_n of_o light_n which_o what_o it_o be_v i_o have_v elsewhere_o already_o show_v five_o that_o the_o dissolution_n of_o sulphureous_a body_n be_v make_v by_o a_o substance_n inherent_a and_o mix_v with_o the_o air_n that_o be_v like_a if_o not_o the_o very_a same_o with_o that_o which_o be_v fix_v in_o saltpetre_n which_o by_o multitude_n of_o experiment_n that_o may_v be_v make_v with_o saltpetre_n will_n i_o think_v most_o evident_o be_v demonstrate_v six_o that_o in_o this_o dissolution_n of_o body_n by_o the_o air_n a_o certain_a part_n be_v unite_v and_o mix_v or_o dissolve_v and_o turn_v into_o the_o air_n and_o make_v to_o fly_v up_o and_o down_o with_o it_o in_o the_o same_o manner_n as_o a_o metalline_a or_o other_o body_n dissolve_v into_o any_o menstruum_n do_v follow_v the_o motion_n and_o progress_v of_o that_o menstruum_fw-la till_o it_o be_v precipitate_v seven_o that_o as_o there_o be_v one_o part_n that_o be_v dissoluble_a by_o the_o air_n so_o be_v there_o other_o part_n with_o which_o the_o part_n of_o the_o air_n mix_v and_o unite_n do_v make_v a_o coagulum_fw-la or_o precipitation_n as_o one_o may_v call_v it_o which_o cause_v it_o to_o be_v separate_v from_o the_o air_n but_o this_o precipitate_a be_v so_o light_a and_o in_o so_o small_a and_o rarify_v or_o porous_a cluster_n that_o it_o be_v very_o volatile_a and_o be_v easy_o carry_v up_o by_o the_o motion_n of_o the_o air_n though_o afterward_o when_o the_o heat_n and_o agitation_n that_o keep_v it_o rarify_v cease_v it_o easy_o condense_n and_o commix_v with_o other_o indissoluble_a part_n it_o stick_v and_o adhere_v to_o the_o next_o body_n it_o meet_v withal_o and_o this_o be_v a_o certain_a salt_n that_o may_v be_v extract_v out_o of_o soot_n eight_o that_o many_o indissoluble_a part_n be_v very_o apt_a and_o prompt_a to_o be_v rarify_v and_o so_o while_o they_o continue_v in_o that_o heat_n and_o agitation_n be_v light_a than_o the_o ambient_fw-la air_n be_v thereby_o thrust_v and_o carry_v upward_o with_o great_a violence_n and_o by_o that_o mean_n carry_v along_o with_o they_o not_o only_o that_o saline_n concrete_a i_o mention_v before_o but_o many_o terrestrial_a or_o indissoluble_a and_o irrarefiable_a part_n nay_o many_o part_n also_o which_o be_v dissoluble_a but_o be_v not_o suffer_v to_o stay_v long_o enough_o 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or_o fixtness_n of_o a_o body_n seem_v to_o consist_v only_o in_o this_o that_o the_o one_o be_v of_o a_o texture_n or_o have_v component_a part_n that_o will_v be_v easy_o rarify_v into_o the_o form_n of_o air_n and_o the_o other_o that_o it_o have_v such_o as_o will_v not_o without_o much_o ado_n be_v bring_v to_o such_o a_o constitution_n and_o this_o be_v that_o part_n which_o remain_v behind_o in_o a_o white_a body_n call_v ash_n which_o contain_v a_o substance_n or_o salt_n which_o chemist_n call_v alkali_n what_o the_o particular_a nature_n of_o each_o of_o these_o body_n be_v i_o shall_v not_o here_o examine_v intend_v it_o in_o another_o place_n but_o shall_v rather_o add_v that_o this_o hypothesis_n do_v so_o exact_o agree_v with_o all_o phaenomena_n of_o fire_n and_o so_o genuine_o explicate_v each_o particular_a circumstance_n that_o i_o have_v hitherto_o observe_v that_o it_o be_v more_o than_o probable_a that_o this_o cause_n which_o i_o have_v assign_v be_v the_o true_a adequate_a real_a and_o only_a cause_n of_o those_o phenomena_n and_o therefore_o i_o shall_v proceed_v a_o little_a further_o to_o show_v the_o nature_n and_o use_n of_o the_o air._n ten_o therefore_o the_o dissolve_v part_n of_o the_o air_n be_v but_o few_o that_o be_v it_o seem_v of_o the_o nature_n of_o those_o saline_n menstruum_n or_o spirit_n that_o have_v very_o much_o phlegm_n mix_v with_o the_o spirit_n and_o therefore_o a_o small_a parcel_n of_o it_o be_v quick_o glut_v and_o will_v dissolve_v no_o more_o and_o therefore_o unless_o some_o fresh_a part_n of_o this_o menstruum_fw-la be_v apply_v to_o the_o body_n to_o be_v dissolve_v the_o action_n cease_v and_o the_o body_n leave_v to_o be_v dissolve_v and_o to_o shine_v which_o be_v the_o indication_n of_o it_o though_o place_v or_o keep_v in_o the_o great_a heat_n whereas_o saltpetre_n be_v a_o menstruum_fw-la when_o melt_v and_o red-hot_a that_o abound_v more_o with_o those_o dissolvent_a particle_n and_o therefore_o as_o a_o small_a quantity_n of_o it_o will_v dissolve_v a_o great_a sulphureous_a body_n so_o will_v the_o dissolution_n be_v very_o quick_a and_o violent_a therefore_o in_o the_o eleven_o place_n it_o be_v observable_a that_o as_o in_o other_o solution_n if_o a_o copious_a and_o quick_a supply_n of_o fresh_a menstruum_fw-la though_o but_o weak_a he_o pour_v on_o or_o apply_v to_o the_o dissoluble_a body_n it_o quick_o consume_v it_o so_o this_o menstruum_fw-la of_o the_o air_n if_o by_o bellows_o or_o any_o other_o such_o contrivance_n it_o be_v copious_o apply_v to_o the_o shine_a body_n be_v find_v to_o dissolve_v it_o as_o soon_o and_o as_o violent_o as_o the_o more_o strong_a menstruum_fw-la of_o melt_a nitre_n therefore_o twelfthly_a it_o seem_v reasonable_a to_o think_v that_o there_o be_v no_o such_o thing_n as_o a_o element_n of_o fire_n that_o shall_v attract_v or_o draw_v up_o the_o flame_n or_o towards_o which_o the_o flame_n shall_v endeavour_v to_o ascend_v out_o of_o a_o desire_n or_o appetite_n of_o unite_n with_o that_o as_o its_o homogeneal_a primitive_a and_o generate_a element_n but_o that_o that_o shine_a transient_a body_n which_o we_o call_v flame_n be_v nothing_o else_o but_o a_o mixture_n of_o air_n and_o volatile_a sulphureous_a part_n of_o dissoluble_a or_o combustible_a body_n which_o be_v act_v upon_o each_o other_o while_o they_o ascend_v that_o be_v flame_n seem_v to_o be_v a_o mixture_n of_o air_n and_o the_o combustible_a volatile_a part_n of_o any_o body_n which_o part_v the_o encompass_v air_n do_v dissolve_v or_o work_v upon_o which_o action_n as_o it_o do_v intend_v the_o heat_n of_o the_o aerial_a part_n of_o the_o dissolvent_a so_o do_v it_o thereby_o further_o rarify_v those_o part_n that_o be_v act_v or_o that_o be_v very_a near_o they_o whereby_o they_o grow_v much_o light_a than_o the_o heavy_a part_n of_o that_o menstruum_fw-la that_o be_v more_o remote_a be_v thereby_o protrude_v and_o drive_v upward_o and_o this_o may_v be_v easy_o observe_v also_o in_o dissolution_n make_v by_o any_o other_o menstruum_fw-la especial_o such_o as_o either_o create_v heat_n or_o bubble_n now_o this_o action_n of_o the_o menstuum_fw-la or_o air_n on_o the_o dissoluble_a part_n be_v make_v with_o such_o violence_n or_o be_v such_o that_o it_o impart_v such_o a_o motion_n or_o pulse_n to_o the_o diaphanous_a part_n of_o the_o air_n as_o i_o have_v elsewhere_o show_v be_v requisite_a to_o produce_v light_n this_o hypothesis_n i_o have_v endeavour_v to_o raise_v from_o a_o infinite_a of_o observation_n and_o experiment_n the_o process_n of_o which_o will_v be_v much_o too_o long_o to_o be_v here_o insert_v and_o will_v perhaps_o another_o time_n afford_v matter_n copious_a enough_o for_o a_o much_o large_a discourse_n the_o air_n be_v a_o subject_a which_o though_o all_o the_o world_n have_v hitherto_o live_v and_o breathe_v in_o and_o be_v unconversant_a about_o have_v yet_o be_v so_o little_a true_o examine_v or_o explain_v that_o a_o diligent_a enquirer_n will_v be_v able_a to_o find_v but_o very_o little_a information_n from_o what_o have_v be_v till_o of_o late_a write_v of_o it_o but_o be_v once_o well_o understand_v it_o will_v i_o doubt_v not_o enable_v a_o man_n to_o render_v a_o intelligible_a nay_o probable_a if_o not_o the_o true_a reason_n of_o all_o the_o phaenomena_n of_o fire_n which_o as_o it_o have_v be_v find_v by_o writer_n and_o philosopher_n of_o all_o age_n a_o matter_n of_o no_o small_a difficulty_n as_o may_v be_v sufficient_o understand_v by_o their_o strange_a hypothesis_n and_o unintelligible_a solution_n of_o some_o few_o phaenomena_n of_o it_o so_o will_v it_o prove_v a_o matter_n of_o no_o small_a concern_v and_o use_v in_o humane_a affair_n as_o i_o shall_v elsewhere_o endeavour_v to_o manifest_v when_o i_o come_v to_o show_v the_o use_n of_o the_o air_n in_o respiration_n and_o for_o the_o preservation_n of_o the_o life_n nay_o for_o the_o conservation_n and_o restauration_n of_o the_o health_n and_o natural_a constitution_n of_o mankind_n as_o well_o as_o all_o other_o aereal_a animal_n as_o also_o the_o use_n of_o this_o principle_n or_o propriety_n of_o the_o air_n in_o chemical_a mechanical_a and_o other_o operation_n in_o this_o place_n i_o have_v only_a time_n to_o hint_n a_o hypothesis_n which_o if_o god_n permit_v i_o life_n and_o opportunity_n i_o may_v elsewhere_o prosecute_v improve_v and_o publish_v in_o the_o mean_a time_n before_o i_o finish_v this_o discourse_n i_o must_v not_o forget_v to_o acquaint_v the_o reader_n that_o have_v have_v the_o liberty_n grant_v i_o of_o make_v some_o trial_n on_o a_o piece_n of_o lignum_fw-la fossil_v show_v to_o the_o royal_a society_n by_o the_o eminent_o ingenious_a and_o learned_a physician_n doctor_n ent_n who_o receive_v it_o for_o a_o present_a from_o the_o famous_a ingenioso_n cavaliero_n de_fw-fr pozzi_n it_o be_v one_o of_o the_o fair_a and_o best_a piece_n of_o lignum_fw-la fossil_v 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hypothesis_n be_v more_o large_o explicate_v in_o the_o description_n of_o charcoal_n to_o conclude_v we_o see_v by_o this_o instance_n how_o much_o experiment_n may_v conduce_v to_o the_o regulate_v of_o philosophical_a notion_n for_o if_o the_o most_o acute_a des_n cartes_n have_v apply_v himself_o experimental_o to_o have_v examine_v what_o substance_n it_o be_v that_o cause_v that_o shine_a of_o the_o fall_a spark_n strike_v from_o a_o flint_n and_o a_o steel_n he_o will_v certain_o have_v a_o little_a alter_v his_o hypothesis_n and_o we_o shall_v have_v find_v that_o his_o ingenious_a principle_n will_v have_v admit_v a_o very_a plausible_a explication_n of_o this_o phaenomenon_n whereas_o by_o not_o examine_v so_o far_o as_o he_o may_v he_o have_v set_v down_o a_o explication_n which_o experiment_n do_v contradict_v but_o before_o i_o leave_v this_o description_n i_o must_v not_o forget_v to_o take_v notice_n of_o the_o globular_a form_n into_o which_o each_o of_o these_o be_v 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the_o discovery_n of_o the_o various_a constitution_n of_o the_o air_n as_o to_o dryness_n and_o moistness_n be_v incomparable_o beyond_o any_o other_o for_o this_o it_o do_v to_o admiration_n the_o manner_n of_o contrive_v it_o so_o as_o to_o perform_v this_o great_a effect_n be_v only_o thus_o provide_v a_o good_a large_a box_n of_o ivory_n about_o four_o inch_n over_o and_o of_o what_o depth_n you_o shall_v judge_v convenient_a according_a to_o your_o intention_n of_o make_v use_n of_o one_o two_o three_o or_o more_o of_o these_o small_a beard_n order_v in_o the_o manner_n which_o i_o shall_v by_o and_o by_o describe_v let_v all_o the_o side_n of_o this_o box_n be_v turn_v of_o basket-work_n which_o here_o in_o london_n be_v easy_o enough_o procure_v full_a of_o hole_n in_o the_o manner_n almost_o of_o a_o lettuce_n the_o big_a or_o more_o the_o hole_n be_v the_o better_a that_o so_o the_o air_n may_v have_v the_o more_o free_a passage_n to_o the_o enclose_a beard_n and_o may_v 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