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the_o tincture_n they_o draw_v and_o even_o in_o the_o more_o gross_a solution_n they_o make_v of_o almost_o all_o concretes_n that_o abound_v either_o with_o mineral_n or_o vegetable_a sulphur_n though_o the_o menstruum_fw-la employ_v about_o these_o solution_n or_o tincture_n be_v never_o so_o limpid_a or_o colourless_a this_o we_o have_v observe_v in_o i_o know_v not_o how_o many_o tincture_n draw_v with_o spirit_n of_o wine_n from_o jalap_n guaicum_fw-la and_o several_a other_o vegetable_n and_o not_o only_o in_o the_o solution_n of_o amber_n benzoin_v and_o divers_a other_o concretes_n make_v with_o the_o same_o menstruum_fw-la but_o also_o in_o divers_a mineral_n tincture_n and_o not_o to_o urge_v that_o familiar_a instance_n of_o the_o ruby_n of_o sulphur_n as_o chemist_n upon_o the_o score_n of_o its_o colour_n call_v the_o solution_n of_o flower_n of_o brimstone_n make_v with_o the_o spirit_n of_o turpentine_n nor_o to_o take_v notice_n of_o other_o more_o know_v example_n of_o the_o aptness_n of_o chemical_a oil_n to_o produce_v a_o red_a colour_n with_o the_o sulphur_n they_o extract_v or_o dissolve_v not_o to_o insist_v i_o say_v upon_o instance_n of_o this_o nature_n i_o shall_v further_o represent_v to_o you_o as_o a_o thing_n remarkable_a that_o both_o acid_n and_o alcalizate_a salt_n though_o in_o most_o other_o case_n of_o such_o contrary_a operation_n in_o reference_n to_o colour_n will_v with_o many_o body_n that_o abound_v with_o sulphureous_a or_o with_o oily_a part_n produce_v a_o red_a as_o be_v manifest_a partly_o in_o the_o more_o vulgar_a instance_n of_o the_o tincture_n or_o solution_n of_o sulphur_n make_v with_o lixivium_n either_o of_o calcine_v tartar_n or_o pot-ash_n and_o other_o obvious_a example_n partly_o by_o this_o that_o the_o true_a glass_n of_o antimony_n extract_v with_o some_o acid_n spirit_n with_o or_o without_o wine_n will_v yield_v a_o red_a tincture_n and_o that_o i_o know_v a_o acid_n liquor_n which_o in_o a_o moment_n will_v turn_v oil_n of_o turpentine_n into_o a_o deep_a red._n but_o among_o the_o many_o instance_n i_o can_v give_v you_o of_o the_o easy_a production_n of_o redness_n by_o the_o operation_n of_o saline_n spirit_n as_o well_o as_o of_o spirit_n of_o wine_n i_o remember_v two_o or_o three_o of_o those_o i_o have_v try_v which_o seem_v remarkable_a enough_o to_o deserve_v to_o be_v mention_v to_o you_o apart_o experiment_n xxxii_o but_o before_o we_o set_v they_o down_o it_o will_v not_o perhaps_o appear_v impertinent_a to_o premise_v that_o there_o seem_v to_o be_v a_o manifest_a disparity_n betwixt_o red_a liquor_n so_o that_o some_o of_o they_o may_v be_v say_v to_o have_v a_o genuine_a redness_n in_o comparison_n of_o other_o that_o have_v a_o yellowish_a redness_n for_o if_o you_o take_v for_o example_n a_o good_a tincture_n of_o chochineel_n dilute_v it_o never_o so_o much_o with_o fair_a water_n you_o will_v not_o
will_v add_v a_o experiment_n of_o our_o own_o make_v before_o we_o meet_v with_o that_o which_o though_o in_o many_o circumstance_n very_o differ_v serve_v to_o prove_v the_o same_o thing_n for_o have_v take_v of_o the_o deep_o red_a juice_n of_o buckthorn_n berry_n which_o i_o buy_v of_o the_o man_n that_o use_v to_o sell_v it_o to_o the_o apothecary_n to_o make_v their_o syrup_n de_fw-fr spina_n cervina_fw-la i_o let_v some_o of_o it_o drop_v upon_o a_o piece_n of_o white_a paper_n and_o have_v leave_v it_o there_o for_o many_o hour_n till_o the_o paper_n be_v grow_v dry_a again_o i_o find_v what_o i_o be_v incline_v to_o suspect_v namely_o that_o this_o juice_n be_v degenerate_v from_o a_o deep_a red_a to_o a_o dirty_a kind_n of_o greyish_a colour_n which_o in_o a_o great_a part_n of_o the_o stain_a paper_n seem_v not_o to_o have_v so_o much_o as_o a_o eye_n of_o red_a though_o a_o little_a spirit_n of_o salt_n or_o dissolve_v alcaly_a will_v turn_v this_o unpleasant_a colour_n as_o former_o i_o tell_v you_o it_o will_v change_v the_o not_o yet_o alter_v juice_n into_o a_o red_a or_o green_n and_o to_o satisfy_v myself_o that_o this_o degeneration_n of_o colour_n do_v not_o proceed_v from_o the_o paper_n i_o drop_v some_o of_o the_o deep_a red_a or_o crimson_a juice_n upon_o a_o white_a glaze_v tile_n and_o suffer_v it_o to_o dry_v on_o there_o i_o find_v that_o even_o in_o that_o body_n on_o which_o it_o can_v not_o soak_v and_o by_o which_o it_o can_v not_o be_v wrought_v it_o nevertheless_o lose_v its_o colour_n and_o these_o instance_n pyrophilus_n i_o be_o the_o more_o careful_a to_o mention_v to_o you_o that_o you_o may_v not_o be_v much_o surprise_v or_o discourage_v if_o you_o shall_v sometime_o miss_v of_o perform_v punctual_o what_o i_o affirm_v myself_o to_o have_v do_v in_o point_n of_o change_a colour_n since_o in_o these_o experiment_n the_o oversight_n or_o neglect_n of_o such_o little_a circumstance_n as_o in_o many_o other_o will_v not_o be_v perhaps_o considerable_a may_v occasion_v the_o miscarrying_a of_o a_o trial._n and_o i_o be_v willing_a also_o to_o take_v this_o occasion_n of_o advertise_v you_o in_o the_o repeat_n of_o the_o experiment_n mention_v in_o this_o treatise_n to_o make_v use_n of_o the_o juice_n of_o vegetable_n and_o other_o thing_n prepare_v for_o your_o trial_n as_o soon_o as_o ever_o they_o be_v ready_a lest_o one_o or_o other_o of_o they_o grow_v less_o fit_a if_o not_o quite_o unfit_a by_o delay_n and_o to_o estimate_v the_o event_n of_o the_o trial_n by_o the_o change_n that_o be_v produce_v present_o upon_o the_o due_a and_o sufficient_a application_n of_o active_n to_o passive_n as_o they_o speak_v because_o in_o many_o case_n the_o effect_n of_o such_o mixture_n may_v not_o be_v last_v and_o the_o new_o produce_v colour_n may_v in_o a_o little_a time_n degenerate_a but_o pyrophilus_n i_o forget_v to_o add_v to_o the_o two_o former_a observation_n late_o make_v about_o vegetable_n a_o three_o of_o the_o same_o import_n make_v in_o mineral_n substance_n by_o tell_v you_o that_o the_o better_a to_o satisfy_v a_o friend_n or_o two_o in_o this_o particular_a i_o sometime_o make_v according_a to_o some_o conjecture_n of_o i_o this_o experiment_n that_o have_v dissolve_v good_a silver_n in_o aquafortis_n and_o precipitate_v it_o with_o spirit_n of_o salt_n upon_o the_o first_o decant_v of_o the_o liquor_n the_o remain_a matter_n will_v be_v pure_o white_a but_o after_o it_o have_v lie_v a_o while_n uncover_v that_o part_n of_o it_o that_o be_v contiguous_a to_o the_o air_n will_v not_o only_o lose_v its_o whiteness_n but_o appear_v of_o a_o very_a dark_a and_o almost_o blackish_a colour_n i_o say_v that_o part_n that_o be_v contiguous_a to_o the_o air_n because_o if_o that_o be_v gentle_o take_v off_o the_o subjacent_a part_n of_o the_o same_o mass_n will_v appear_v very_o white_a till_o that_o also_o have_v continue_v a_o while_n expose_v to_o the_o air_n will_v likewise_o degenerate_a now_o whether_o the_o air_n perform_v these_o thing_n by_o the_o mean_n of_o a_o subtle_a salt_n which_o we_o elsewhere_o show_v it_o not_o to_o be_v destitute_a of_o or_o by_o a_o pierce_a moisture_n that_o be_v apt_a easy_o to_o insinuate_v itself_o into_o the_o pore_n of_o some_o body_n and_o thereby_o change_v their_o texture_n and_o so_o their_o colour_n or_o by_o solicit_v the_o avolation_n of_o certain_a part_n of_o the_o body_n to_o which_o it_o be_v contiguous_a or_o by_o some_o other_o way_n which_o possible_o i_o may_v elsewhere_o propose_v and_o consider_v i_o have_v not_o now_o the_o leisure_n to_o discourse_v and_o for_o the_o same_o reason_n though_o i_o can_v add_v many_o other_o instance_n of_o what_o i_o former_o note_v touch_v the_o emergency_n of_o redness_n upon_o the_o digestion_n of_o many_o body_n insomuch_o that_o i_o have_v often_o see_v upon_o the_o border_n of_o france_n and_o probable_o we_o may_v have_v the_o like_a in_o england_n a_o sort_n of_o pear_n which_o digest_v for_o some_o time_n with_o a_o little_a wine_n in_o a_o vessel_n exact_o close_v will_v in_o not_o many_o hour_n appear_v throughout_o of_o a_o deep_a red_a colour_n as_o also_o that_o of_o the_o juice_n wherein_o they_o be_v stew_v become_v but_o even_o on_o pure_a and_o white_a salt_n of_o tartar_n pure_a spirit_n of_o wine_n as_o clear_a as_o rock-water_n will_v as_o we_o elsewhere_o declare_v by_o long_a digestion_n acquire_v a_o redness_n though_o i_o say_v such_o instance_n may_v be_v multiply_v and_o though_o there_o be_v some_o other_o obvious_a change_n of_o colour_n which_o happen_v so_o frequent_o that_o they_o can_v but_o be_v as_o well_o considerable_a as_o notorious_a such_o as_o be_v the_o blackness_n of_o almost_o all_o body_n burn_v in_o the_o open_a air_n yet_o our_o haste_n invite_v we_o to_o resign_v you_o the_o exercise_n of_o inquire_v into_o the_o cause_n of_o these_o change_n and_o certain_o the_o reason_n both_o why_o the_o soot_v of_o such_o differ_a body_n be_v almost_o all_o of_o they_o all_o black_a why_o so_o much_o the_o great_a part_n of_o vegetable_n shall_v be_v rather_o green_a than_o of_o any_o other_o colour_n and_o particular_o which_o more_o direct_o concern_v this_o place_n why_o gentle_a heat_n do_v so_o frequent_o in_o chemical_a operation_n produce_v rather_o a_o redness_n than_o another_o colour_n in_o digest_v menstruum_n not_o only_o sulphureous_a as_o spirit_n of_o wine_n but_o saline_n as_o spirit_n of_o vinegar_n may_v be_v very_o well_o worth_a a_o serious_a inquiry_n which_o i_o shall_v therefore_o recommend_v to_o pyrophilus_n and_o his_o ingenious_a friend_n experiment_n xxxvii_o it_o may_v seem_v somewhat_o strange_a that_o if_o you_o take_v the_o crimson_a solution_n of_o cochineel_n or_o the_o juice_n of_o black_a cherry_n and_o of_o some_o other_o vegetable_n that_o afford_v the_o like_a colour_n which_o because_o many_o take_v but_o for_o a_o deep_a red_a we_o do_v with_o they_o sometime_o call_v it_o so_o and_o let_v some_o of_o it_o fall_v upon_o a_o piece_n of_o paper_n a_o drop_n or_o two_o of_o a_o acid_n spirit_n such_o as_o spirit_n of_o salt_n or_o aquafortis_n will_v immediate_o turn_v it_o into_o a_o fair_a red._n whereas_o if_o you_o make_v a_o infusion_n of_o brazil_n in_o fair_a water_n and_o drop_v a_o little_a spirit_n of_o salt_n or_o aquafortis_n into_o it_o that_o will_v destroy_v its_o redness_n and_o leave_v the_o liquor_n of_o a_o yellow_a sometime_o pale_a i_o may_v perhaps_o plausible_o enough_o say_v on_o this_o occasion_n that_o if_o we_o consider_v the_o case_n a_o little_a more_o attentive_o we_o may_v take_v notice_n that_o the_o action_n of_o the_o acid_n spirit_n seem_v in_o both_o case_n but_o to_o weaken_v the_o colour_n of_o the_o liquor_n on_o which_o it_o fall_v and_o so_o though_o it_o destroy_v redness_n in_o the_o tincture_n of_o brazil_n as_o well_o as_o produce_v red_a in_o the_o tincture_n of_o chochineel_n its_o operation_n may_v be_v uniform_a enough_o since_o as_o crimson_a seem_v to_o be_v little_a else_o than_o a_o very_a deep_a red_a with_o perhaps_o a_o eye_n of_o blue_n so_o some_o kind_n of_o red_a seem_v as_o i_o have_v late_o note_v to_o be_v little_a else_o than_o heighten_v yellow_a and_o consequent_o in_o such_o body_n the_o yellow_a seem_v to_o be_v but_o a_o diluted_a red._n and_o according_o alcalizate_a solution_n and_o urinous_a spirit_n which_o seem_v dispose_v to_o deepen_v the_o colour_n of_o the_o juice_n and_o liquor_n of_o most_o vegetable_n will_v not_o only_o restore_v the_o solution_n of_o cochineel_n and_o the_o infusion_n of_o brazil_n to_o the_o crimson_a whence_o the_o spirit_n of_o salt_n have_v change_v they_o into_o a_o true_a red_a but_o will_v also_o as_o i_o late_o tell_v you_o not_o