the_o rule_n mention_v above_o in_o the_o first_o proposition_n that_o the_o quantity_n of_o the_o water_n that_o run_v through_o the_o chanellet_n be_v v_o g._n a_o hundred_o barrel_n in_o the_o space_n of_o 15_o second_o minute_n of_o a_o hour_n it_o be_v manifest_a that_o the_o water_n which_o run_v through_o the_o great_a channel_n in_o the_o say_a time_n of_o 35_o min._n sec._n shall_v be_v about_o 600_o barrel_n the_o same_o operation_n perform_v another_o way_n and_o because_o very_o often_o in_o apply_v the_o theory_n to_o practise_v it_o happen_v that_o all_o the_o necessary_a particular_n in_o the_o theory_n can_v so_o easy_o be_v put_v in_o execution_n therefore_o we_o will_v here_o add_v another_o way_n of_o perform_v the_o same_o problem_n if_o it_o shall_v chance_v to_o happen_v that_o the_o chanellet_n can_v not_o commodious_o be_v divert_v from_o the_o great_a channel_n but_o that_o it_o be_v easy_a for_o the_o water_n of_o another_o small_a channel_n to_o be_v bring_v into_o the_o great_a channel_n which_o water_n of_o the_o small_a channel_n may_v be_v easy_o measure_v as_o have_v be_v show_v in_o the_o first_o problem_n or_o in_o case_n that_o there_o do_v fall_v into_o a_o great_a channel_n a_o lesser_a channel_n that_o may_v be_v divert_v and_o measure_v therefore_o i_o say_v in_o the_o first_o case_n if_o we_o will_v measure_v the_o quantity_n of_o the_o water_n that_o run_v in_o a_o certain_a time_n through_o the_o great_a channel_n into_o which_o another_o lesser_a channel_n that_o be_v measurable_a may_v be_v bring_v we_o must_v first_o exact_o measure_v the_o chanellet_n and_o then_o observe_v the_o quick_a height_n of_o the_o great_a channel_n before_o the_o introduction_n of_o the_o lesser_a and_o have_v bring_v in_o the_o say_a chanellet_n we_o must_v agnin_n find_v the_o proportion_n that_o the_o water_n of_o the_o chanellet_n have_v to_o all_o the_o water_n of_o the_o great_a channel_n for_o these_o term_n of_o the_o proportion_n be_v know_v as_o also_o the_o quantity_n of_o the_o water_n of_o the_o chanellet_n we_o shall_v also_o come_v to_o know_v the_o quantity_n of_o the_o water_n that_o run_v through_o the_o great_a channel_n it_o be_v likewise_o manifest_a that_o we_o shall_v obtain_v our_o intent_n if_o the_o case_n be_v that_o there_o enter_v into_o the_o great_a channel_n another_o lesser_a channel_n that_o be_v measurable_a and_o that_o may_v be_v divert_v consideration_n it_o will_v be_v necessary_a to_o make_v use_n of_o this_o doctrine_n in_o the_o distribution_n of_o the_o water_n that_o be_v employ_v to_o overflow_v the_o field_n as_o be_v use_v in_o the_o brescian_a cremonese_n bergamase_v lodigian_a milanese_n territory_n and_o many_o other_o place_n where_o very_o great_a suit_n and_o difference_n arise_v which_o not_o be_v to_o be_v determine_v with_o intelligible_a reason_n come_v oftentimes_o to_o be_v decide_v by_o force_n of_o arm_n and_o instead_o of_o flow_v their_o ground_n with_o water_n they_o cruel_o flow_v they_o with_o the_o shed_n of_o humane_a blood_n impious_o invert_v the_o course_n of_o peace_n and_o justice_n sow_v such_o disorder_n and_o feud_n as_o that_o they_o be_v sometime_o accompany_v with_o the_o ruin_n of_o whole_a city_n or_o else_o unprofitable_o charge_v they_o with_o vain_a and_o sometime_o prejudicial_a expense_n propos_fw-fr iv._o theor._n ii_o if_o a_o river_n increase_v in_o quick_a height_n the_o quantity_n of_o water_n which_o the_o river_n discharge_v after_o the_o increase_n have_v the_o proportion_n compound_v of_o the_o proportion_n of_o the_o quick_a height_n to_o the_o quick_a height_n and_o of_o the_o velocity_n to_o the_o velocity_n let_v there_o be_v a_o river_n which_o whilst_o it_o be_v low_a run_v through_o the_o regulator_n df_n with_o the_o quick_a height_n ab_fw-la and_o afterward_o let_v a_o flood_n come_v and_o then_o let_v it_o run_v with_o the_o height_n db_n i_o say_v that_o the_o quantity_n of_o the_o water_n that_o be_v discharge_v through_o df_n to_o that_o which_o discharge_v through_o of_o have_v the_o proportion_n compound_v of_o the_o proportion_n of_o the_o velocity_n through_o df_n to_o the_o velocity_n through_o of_o and_o of_o the_o height_n db_n to_o the_o height_n ab_fw-la as_o the_o velocity_n through_o df_n be_v to_o the_o velocity_n through_o of_o so_o let_v the_o line_n r_o be_v to_o the_o line_n s_o and_o as_o the_o height_n db_n be_v to_o the_o height_n ab_fw-la so_o let_v the_o line_n s_o be_v to_o the_o line_n t._n and_o let_v a_o section_n be_v suppose_v lmn_n equal_a to_o the_o section_n df_n in_o height_n and_o length_n but_o let_v it_o be_v in_o velocity_n equal_a to_o the_o section_n af._n therefore_o the_o quantity_n of_o the_o water_n that_o run_v through_o df_n to_o that_o which_o run_v through_o ln_o shall_v be_v as_o the_o velocity_n through_o df_n to_o the_o velocity_n of_o ln_o that_o be_v to_o the_o velocity_n through_o ln_o that_o be_v to_o the_o velocity_n through_o af._n therefore_o the_o quantity_n of_o water_n which_o run_v through_o df_n to_o that_o which_o pass_v through_o ln_o shall_v have_v the_o proportion_n that_o r_o have_v to_o saint_n but_o the_o quantity_n of_o the_o water_n that_o run_v through_o ln_o to_o that_o which_o run_v through_o of_o the_o section_n be_v equal_o swift_a shall_v have_v the_o proportion_n that_o the_o section_n ln_o have_v to_o the_o section_n of_o that_o be_v that_o the_o height_n bd_o have_v to_o the_o height_n basilius_n that_o be_v that_o saint_n have_v to_o t._n therefore_o by_o equal_a proportion_n the_o quantity_n of_o the_o water_n which_o run_v by_o df_n to_o that_o which_o run_v by_o of_o shall_v have_v the_o proportion_n of_o r_o to_o t_n that_o be_v shall_v be_v compound_v of_o the_o proportion_n of_o the_o height_n db_n to_o the_o height_n ab_fw-la and_o of_o the_o velocity_n through_o df_n to_o the_o velocity_n through_o af._n and_o therefore_o if_o a_o river_n increase_v in_o quick_a height_n the_o quantity_n of_o the_o water_n that_o run_v after_o the_o increase_n to_o that_o which_o run_v before_o the_o increase_n have_v the_o proportion_n compound_v etc._n etc._n which_o be_v to_o be_v demonstrate_v corollary_n i._n hence_o it_o follow_v that_o we_o have_v show_v that_o the_o quantity_n of_o the_o water_n which_o run_v whilst_o the_o river_n be_v high_a to_o that_o which_o run_v whilst_o it_o be_v low_a have_v the_o proportion_n compound_v of_o the_o velocity_n to_o the_o velocity_n and_o of_o the_o height_n to_o the_o height_n and_o it_o have_v be_v demonstrate_v that_o the_o velocity_n to_o the_o velocity_n be_v as_o the_o height_n to_o the_o height_n it_o follow_v i_o say_v that_o the_o quantity_n of_o the_o water_n that_o run_v whilst_o the_o river_n be_v high_a to_o that_o which_o run_v whilst_o it_o be_v low_a have_v duplicate_v proportion_n of_o the_o height_n to_o the_o height_n that_o be_v the_o proportion_n that_o the_o square_n of_o the_o height_n have_v corollary_n ii_o upon_o which_o thing_n depend_v the_o reason_n of_o that_o which_o i_o have_v say_v in_o my_o second_o consideration_n that_o if_o by_o the_o diversion_n of59._o of_o the_o water_n that_o enter_v by_o the_o river_n into_o the_o moor_n or_o fen_n the_o water_n be_v abate_v such_o a_o measure_n that_o same_o shall_v be_v only_o one_o three_o of_o its_o whole_a height_n but_o moreover_o divert_v the_o 49_o it_o shall_v abate_v two_o other_o three_o a_o most_o principal_a point_n and_o such_o that_o it_o be_v not_o have_v be_v well_o understand_v have_v cause_v very_o great_a disorder_n and_o there_o will_v now_o more_o than_o ever_o follow_v extreme_a damage_n if_o one_o shall_v put_v in_o execution_n the_o diversion_n of_o the_o sile_z and_o other_o river_n and_o it_o be_v manifest_a that_o in_o the_o same_o manner_n wherewith_o it_o have_v be_v demonstrate_v that_o the_o quantity_n of_o the_o water_n increase_v quadruple_a the_o height_n will_v increase_v only_o double_a and_o the_o quantity_n increase_v nonuple_n the_o height_n increase_v triple_a so_o that_o by_o add_v to_o unit_v all_o the_o odd_a number_n according_a to_o their_o series_n the_o height_n increase_v according_a to_o the_o natural_a progression_n of_o all_o the_o number_n from_o unit_n as_o for_o example_n there_o pass_v through_o a_o regulator_n such_o a_o certain_a quantity_n of_o water_n in_o one_o time_n add_v three_o of_o those_o measure_n the_o quick_a height_n be_v two_o of_o those_o part_n which_o at_o first_o be_v one_o and_o continue_v to_o add_v five_o of_o those_o say_a measure_n the_o height_n be_v three_o of_o those_o part_n which_o at_o first_o be_v one_o and_o thus_o add_v seven_o and_o then_o nine_o and_o then_o 11._o and_o then_o 13_o etc._n etc._n the_o height_n shall_v be_v 4._o then_o 5_o than_o 6._o then_o 7_o
in_o the_o low_a part_n namely_o below_o the_o breach_n there_o be_v beget_v in_o the_o channel_n of_o the_o river_n a_o certain_a ridge_n or_o shelf_n that_o be_v the_o bottom_n of_o the_o river_n be_v raise_v as_o be_v sufficient_o manifest_a by_o experience_n and_o thus_o just_a in_o the_o same_o manner_n cut_v the_o bank_n at_o bondeno_n there_o be_v at_o it_o be_v a_o breach_n make_v from_o which_o follow_v the_o rise_n in_o the_o low_a part_n of_o the_o main_a po_n be_v past_o the_o mouth_n of_o pamaro_n which_o thing_n how_o pernicious_a it_o be_v let_v any_o one_o judge_n that_o understand_v these_o matter_n and_o therefore_o both_o for_o the_o small_a benefit_n and_o so_o many_o harm_n that_o ensue_v from_o maintain_v this_o diversion_n i_o shall_v think_v it_o be_v more_o sound_a advice_n to_o keep_v that_o bank_n always_o whole_a at_o bondeno_n or_o in_o any_o other_o convenient_a place_n and_o not_o to_o permit_v that_o the_o water_n of_o the_o grand_a po_n shall_v ever_o come_v near_o to_o ferara_n corollary_n fourteen_o in_o the_o grand_a river_n which_o fall_v into_o the_o sea_n as_o here_o in_o italy_n po_n adige_n artesia_n and_o arno_n which_o be_v arm_v with_o bank_n against_o their_o excrescency_n it_o be_v observe_v that_o far_o from_o the_o sea_n they_o need_v bank_n of_o a_o notable_a height_n which_o height_n go_v afterward_o by_o degree_n diminish_v the_o more_o it_o approach_v to_o the_o seacoast_n in_o such_o sort_n that_o the_o po_n distant_a from_o the_o sea_n about_o fifty_o or_o sixty_o mile_n at_o ferara_n shall_v have_v bank_n that_o be_v above_o twenty_o foot_n high_o than_o the_o ordinary_a water-mark_n but_o ten_o or_o twelve_o mile_n from_o the_o sea_n the_o bank_n be_v not_o twelve_o foot_n high_o than_o the_o say_v ordinary_a water-mark_n though_o the_o breadth_n of_o the_o river_n be_v the_o same_o so_o that_o the_o excrescence_n of_o the_o same_o innundation_n happen_v to_o be_v far_o great_a in_o measure_n remote_a from_o the_o sea_n then_o near_o and_o yet_o it_o shall_v seem_v that_o the_o same_o quantity_n of_o water_n pass_v by_o every_o place_n the_o river_n shall_v need_v to_o have_v the_o same_o altitude_n of_o bank_n in_o all_o place_n but_o we_o by_o our_o principle_n and_o fundamental_o may_v be_v able_a to_o render_v the_o reason_n of_o that_o effect_n and_o say_v that_o that_o excess_n of_o quantity_n of_o water_n above_o the_o ordinary_a water_n go_v always_o acquire_v great_a velocity_n the_o near_a it_o approach_v the_o sea_n and_o therefore_o decrease_v in_o measure_n and_o consequent_o in_o height_n and_o this_o perhaps_o may_v have_v be_v the_o cause_n in_o great_a part_n why_o the_o tiber_n in_o the_o innundation_n anno_fw-la 1578._o issue_v not_o forth_o of_o its_o channel_n below_o rome_n towards_o the_o sea_n corollary_n xv._n from_o the_o same_o doctrine_n may_v be_v render_v a_o most_o manifest_a reason_n why_o the_o fall_a water_n go_v lessen_v in_o their_o descent_n so_o that_o the_o same_o fall_a water_n measure_v at_o the_o begin_n of_o its_o fall_n be_v great_a and_o big_a and_o afterward_o by_o degree_n lessen_v in_o measure_n the_o more_o it_o be_v remote_a from_o the_o begin_n of_o the_o fall_n which_o depend_v on_o no_o other_o than_o on_o the_o acquisition_n which_o it_o successive_o make_v of_o great_a velocity_n it_o be_v a_o most_o familiar_a conclusion_n among_o philosopher_n that_o grave_a body_n fall_v the_o more_o they_o remove_v from_o the_o begin_n of_o their_o motion_n the_o more_o they_o acquire_v of_o swiftness_n and_o therefore_o the_o water_n as_o a_o grave_a body_n falling_z gradual_o velocitates_fw-la and_o therefore_o decrease_v in_o measure_n and_o lessen_v corollary_n xvi_o and_o on_o the_o contrary_a the_o spirting_n of_o a_o fountain_n of_o water_n which_o spring_n on_o high_a work_v a_o contrary_a effect_n namely_o in_o the_o beginning_n they_o be_v small_a and_o afterward_o become_v great_a and_o big_a and_o the_o reason_n be_v most_o manifest_a because_o in_o the_o beginning_n they_o be_v very_o swift_a and_o afterward_o gradual_o relent_v their_o impetuosity_n and_o motion_n so_o that_o in_o the_o begin_n of_o the_o excursion_n that_o they_o make_v they_o ought_v to_o be_v small_a and_o afterward_o to_o grow_v big_a as_o in_o the_o effect_n be_v see_v appendix_n i._o into_o the_o error_n of_o not_o consider_v how_o much_o the_o different_a velocity_n of_o the_o same_o run_a water_n in_o several_a place_n of_o its_o current_n be_v able_a to_o change_v the_o measure_n of_o the_o same_o water_n and_o to_o make_v it_o great_a or_o less_o i_o think_v if_o i_o be_v not_o deceive_v that_o ginlio_n frontino_n a_o noble_a ancient_a writer_n may_v have_v fall_v in_o the_o second_o book_n which_o he_o write_v of_o the_o aqueduct_n of_o the_o city_n of_o rome_n whilst_o find_v the_o measure_n of_o the_o water_n water_n commentariis_fw-la less_o than_o it_o be_v in_o erogatione_fw-la 1263._o quinary_n he_o think_v that_o so_o much_o difference_n may_v proceed_v from_o the_o negligence_n of_o the_o measure_n and_o when_o afterward_o with_o his_o own_o industry_n he_o measure_v the_o same_o water_n at_o the_o begin_n of_o the_o aqueduct_n find_v it_o near_o 10000_o quinary_n big_a than_o it_o be_v in_o commentariis_fw-la he_o judge_v that_o the_o overplus_n be_v imbezile_v by_o minister_n and_o partaker_n which_o in_o part_n may_v be_v so_o for_o it_o be_v but_o too_o true_a that_o the_o public_a be_v almost_o always_o defraud_v yet_o nevertheless_o i_o very_o believe_v withal_o that_o beside_o the_o fraud_n of_o these_o officer_n the_o velocity_n of_o the_o water_n in_o the_o place_n wherein_o frontino_n measure_v it_o may_v be_v different_a from_o those_o velocity_n which_o be_v find_v in_o other_o place_n before_o measure_v by_o other_o and_o therefore_o the_o measure_n of_o the_o water_n may_v yea_o ought_v necessary_o to_o be_v different_a it_o have_v be_v by_o we_o demonstrate_v that_o the_o measure_n of_o the_o same_o run_a water_n have_v reciprocal_a proportion_n to_o their_o velocity_n which_o frontino_n not_o well_o consider_v and_o find_v the_o water_n in_o commentariis_fw-la 12755._o quinary_n in_o erogatione_fw-la 14018_o and_o in_o his_o own_o measure_n ad_fw-la capita_fw-la ductuum_fw-la at_o the_o head_n of_o the_o fountain_n 22755._o quinary_n or_o thereabouts_o he_o think_v that_o in_o all_o these_o place_n there_o past_a different_a quantity_n of_o water_n namely_o great_a at_o the_o fountain_n head_n than_o that_o which_o be_v in_o erogatione_fw-la and_o this_o he_o judge_v great_a than_o that_o which_o be_v in_o commentariis_fw-la appendix_n ii_o a_o like_a mistake_n chance_v late_o in_o the_o aqueduct_v of_o acqua-paola_n which_o water_n shall_v be_v 2000_o inch_n and_o so_o many_o effective_o aught_o to_o be_v allow_v and_o it_o have_v be_v give_v in_o so_o to_o be_v by_o the_o signor_n of_o bracciano_n to_o the_o apostolic-chamber_n and_o there_o be_v a_o measure_n thereof_o make_v at_o the_o begin_n of_o the_o aqueduct_v which_o measure_n prove_v afterward_o much_o less_o and_o short_a consider_v and_o take_v in_o rome_n and_o thence_o follow_v discontent_n and_o great_a disorder_n and_o all_o because_o this_o property_n of_o running-water_n of_o increase_v in_o measure_n where_o the_o velocity_n decrease_v and_o of_o diminish_v in_o measure_n where_o the_o velocity_n augment_v be_v not_o look_v into_o appendix_n iii_o a_o like_a error_n in_o my_o judgement_n have_v be_v commit_v by_o all_o those_o learned_a man_n which_o to_o prevent_v the_o diversion_n of_o the_o reno_n of_o bologna_n into_o po_n by_o the_o channel_n through_o which_o it_o at_o present_a run_v judge_v that_o the_o reno_n be_v in_o its_o great_a excrescence_n about_o 2000_o foot_n and_o the_o po_n be_v near_o 1000_o foot_n broad_a they_o judge_v i_o say_v that_o let_v the_o reno_n into_o po_n it_o will_v have_v raise_v the_o water_n of_o po_n two_o foot_n from_o which_o rise_n they_o conclude_v afterward_o most_o exorbitant_a disorder_n either_o of_o extraordinary_a inundation_n or_o else_o of_o immense_a and_o intolerable_a expense_n to_o the_o people_n in_o raise_v the_o bank_n of_o po_n and_o reno_n and_o with_o such_o like_a weakness_n often_o vain_o disturb_v the_o mind_n of_o the_o person_n concern_v but_o now_o from_o the_o thing_n demonstrare_v it_o be_v manifest_a that_o the_o measure_n of_o the_o reno_n in_o reno_n will_v be_v different_a from_o the_o measure_n of_o reno_n in_o po_n in_o case_n that_o the_o velocity_n of_o the_o reno_n in_o po_n shall_v differ_v from_o the_o velocity_n of_o reno_n in_o reno_n as_o be_v more_o exact_o determine_v in_o the_o four_o proposition_n appendix_n iu._n no_o less_o likewise_o be_v those_o ingeneer_n and_o artist_n deceive_v that_o have_v affirm_v that_o let_v the_o reno_n into_o po_n there_o will_v be_v
great_a convenience_n in_o travail_v that_o without_o the_o least_o trouble_n they_o can_v go_v with_o their_o family_n house_n and_o whole_a city_n to_o place_n far_o remote_a like_a as_o i_o say_v i_o be_o certain_a such_o a_o person_n though_o of_o never_o so_o pierce_v a_o imagination_n can_v never_o fancy_v to_o himself_o fish_n the_o ocean_n ship_n fleet_n armado_n at_o sea_n thus_o and_o much_o more_o easy_o may_v it_o happn_v that_o in_o the_o moon_n remote_a from_o we_o by_o so_o great_a a_o space_n and_o of_o a_o substance_n perchance_o very_o different_a from_o the_o earth_n there_o may_v be_v matter_n and_o operation_n not_o only_o wide_o off_o but_o altogether_o beyond_o all_o our_o imagination_n as_o be_v such_o as_o have_v no_o resemblance_n to_o we_o and_o therefore_o whole_o inexcogitable_a in_o regard_n that_o what_o we_o imagine_v to_o ourselves_o must_v necessary_o be_v either_o a_o thing_n already_o see_v or_o a_o composition_n of_o thing_n or_o part_n of_o thing_n 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problem_n ii_o a_o channel_n of_o water_n be_v give_v who_o breadth_n exceed_v not_o twenty_o palm_n or_o thereabouts_o and_o who_o quick_a height_n be_v less_o than_o five_o palm_n to_o measure_v the_o quantity_n of_o the_o water_n that_o run_v through_o the_o channel_n in_o a_o time_n give_v place_v in_o the_o channel_n a_o regulator_n and_o observe_v the_o quick_a height_n in_o the_o say_a regulator_n then_o let_v the_o water_n be_v turn_v away_o from_o the_o channel_n by_o a_o chanellet_n of_o three_o or_o four_o palm_n in_o breadth_n or_o thereabouts_o and_o that_o be_v do_v measure_v the_o quantity_n of_o the_o water_n which_o pass_v through_o the_o say_a chanellet_n as_o have_v be_v teach_v in_o the_o second_o proposition_n and_o at_o the_o same_o time_n observe_v exact_o how_o much_o the_o quick_a height_n shall_v be_v abate_v in_o the_o great_a channel_n by_o mean_n of_o the_o diversion_n of_o the_o chanellet_n and_o all_o these_o particular_n be_v perform_v multiply_v the_o quick_a height_n of_o the_o great_a channel_n into_o itself_o and_o likewise_o multiply_v into_o itself_o the_o lesser_a height_n of_o the_o say_v big_a channel_n and_o the_o lesser_a square_a be_v take_v from_o the_o great_a the_o remainder_n shall_v have_v the_o same_o proportion_n to_o the_o whole_a great_a square_n as_o the_o water_n of_o the_o chanellet_n divert_v have_v to_o the_o water_n of_o the_o big_a channel_n and_o because_o the_o water_n of_o the_o chanellet_n be_v know_v by_o the_o method_n say_v down_o in_o the_o first_o theorem_n and_o the_o term_n of_o the_o theorem_fw-la be_v also_o know_v the_o quantity_n of_o the_o water_n which_o run_v through_o the_o big_a channel_n shall_v be_v also_o know_v by_o the_o golden_a rule_n which_o be_v that_o that_o be_v desire_v to_o be_v know_v we_o will_v explain_v the_o whole_a business_n by_o a_o example_n let_v a_o channel_n be_v for_o example_n 15_o palm_n broad_a its_o quick_a height_n before_o its_o diversion_n by_o the_o chanellet_n shall_v be_v suppose_v to_o be_v 24_o inch_n but_o after_o the_o diversion_n let_v the_o quick_a height_n of_o the_o channel_n be_v only_o 22_o inch_n therefore_o the_o great_a height_n to_o the_o lesser_a be_v as_o the_o number_n 11._o to_o 12._o but_o the_o square_n of_o 11._o be_v 121_o and_o the_o square_a of_o 12._o be_v 144_o the_o difference_n between_o the_o say_v lesser_a square_a and_o the_o great_a be_v 23._o therefore_o the_o divert_a water_n be_v to_o the_o whole_a water_n as_o 23._o to_o 144_o which_o be_v well_o near_o as_o 1_o to_o 6â—_n and_o that_o be_v the_o proportion_n that_o the_o quantity_n of_o the_o water_n which_o run_v through_o the_o chanellet_n shall_v have_v to_o all_o the_o water_n that_o run_v through_o the_o great_a channel_n now_o if_o we_o shall_v find_v by_o
strange_a and_o unlikely_a to_o many_o other_o the_o point_n be_v that_o i_o say_v that_o by_o raise_v the_o level_n of_o fiume_n morto_fw-la one_o half_a brace_n only_o at_o its_o mouth_n it_o will_v penipenitrate_v into_o serchio_n far_a than_o it_o will_v into_o the_o sea_n it_o shall_v cause_v the_o water_n to_o rise_v three_o or_o perhaps_o more_o brace_n upon_o the_o field_n towards_o pisa_n and_o still_o more_o by_o degree_n as_o they_o shall_v recede_v far_o from_o the_o seaside_n and_o thus_o there_o will_v follow_v very_o great_a inundation_n and_o considerable_a mischief_n and_o to_o know_v that_o this_o be_v true_a you_o be_v to_o take_v notice_n of_o a_o accident_n which_o i_o give_v warning_n of_o in_o my_o discourse_n of_o the_o measure_n of_o run_v water_n where_o also_o i_o give_v the_o reason_n thereof_o 1._o coral_n 14._o the_o accident_n be_v this_o that_o there_o come_v a_o land-flood_n for_o example_n into_o arno_n which_o make_v it_o to_o rise_v above_o its_o ordinary_a mouth_n within_o pisa_n or_o a_o little_a above_o or_o below_o the_o city_n six_o or_o seven_o brace_n this_o same_o height_n become_v always_o lesser_a and_o lesser_a the_o more_o we_o approach_v towards_o the_o seaside_n insomuch_o that_o near_o to_o the_o sea_n the_o say_a river_n shall_v be_v raise_v hardly_o half_a a_o brace_n whence_o it_o follow_v of_o necessary_a consequence_n that_o shall_v i_o again_o be_v at_o the_o seaside_n and_o know_v nothing_o of_o what_o happen_v shall_v see_v the_o river_n arno_n raise_v by_o the_o accession_n of_o a_o land-flood_n one_o three_o of_o a_o brace_n i_o can_v certain_o infer_v that_o the_o same_o river_n be_v raise_v in_o pisa_n those_o same_o six_o or_o seven_o brace_n and_o that_o which_o i_o say_v of_o arno_n be_v true_a of_o all_o river_n that_o fall_v into_o the_o sea_n which_o thing_n be_v true_a it_o be_v necessary_a to_o make_v great_a account_n of_o every_o small_a rise_n that_o fiume_n morto_fw-la make_v towards_o the_o seaside_n by_o fall_v into_o serchio_n for_o although_o the_o rise_n of_o fiume_n morto_fw-la by_o be_v to_o disgorge_v its_o water_n into_o serchio_n towards_o the_o sea_n be_v only_o a_o quarter_n of_o a_o brace_n we_o may_v very_o well_o be_v sure_a that_o far_o from_o the_o sea_n about_o pisa_n and_o upon_o those_o field_n the_o rise_n shall_v be_v much_o great_a and_o shall_v become_v two_o or_o three_o brace_n and_o because_o the_o country_n lie_v low_a that_o same_o â—ise_v will_v cause_v a_o continual_a innundation_n of_o the_o plain_n like_a as_o it_o do_v before_o i_o cause_v the_o mouth_n to_o be_v open_v into_o the_o sea_n and_o therefore_o i_o conclude_v that_o the_o mouth_n of_o fiume_n morto_fw-la aught_o by_o no_o mean_n to_o be_v open_v into_o serchio_n but_o aught_o to_o be_v continue_v into_o the_o sea_n use_v all_o diligence_n to_o keep_v it_o open_v after_o the_o manner_n aforesaid_a so_o soon_o as_o ever_o the_o wind_n shall_v be_v lay_v and_o if_o they_o shall_v do_v otherwise_o i_o confident_o affirm_v that_o there_o will_v daily_o follow_v great_a damage_n not_o only_o in_o the_o plain_n but_o also_o in_o the_o wholesomeness_n of_o the_o air_n as_o have_v be_v see_v in_o time_n past_a and_o again_o it_o ought_v with_o all_o care_n to_o be_v procure_v that_o no_o water_n do_v by_o any_o mean_v run_v or_o fall_v from_o the_o trench_n of_o libra_n into_o the_o plain_a of_o pisa_n for_o these_o water_n be_v to_o discharge_v into_o fiume_n morto_fw-la they_o maintain_v it_o much_o high_a than_o be_v imagine_v according_a to_o that_o which_o i_o have_v demonstrate_v in_o my_o consideration_n upon_o the_o state_n of_o the_o lake_n of_o venice_n i_o have_v say_v but_o little_a but_o i_o speak_v to_o you_o who_o understand_v much_o and_o i_o submit_v all_o to_o the_o most_o refine_a judgement_n of_o our_o most_o serene_a prince_n leopold_n who_o hand_n i_o beseech_v you_o in_o all_o humility_n to_o kiss_v in_o my_o name_n and_o implore_v the_o continuance_n of_o his_o princely_a favour_n to_o i_o and_o so_o desire_v your_o prayer_n to_o god_n for_o i_o i_o take_v my_o leave_n rome_n 1_o feb._n 1642._o your_o most_o affectionate_a servant_n d._n benedetto_n castelli_n the_o answer_n to_o a_o letter_n write_v by_o bartolotti_n touch_v the_o difficultye_n observe_v the_o former_a part_n of_o the_o letter_n be_v omit_v and_o the_o discourse_n begin_v at_o the_o first_o head_n and_o first_o i_o say_v whereas_o i_o suppose_v that_o the_o level_n of_o the_o serchio_n be_v high_a than_o that_o of_o fiume_n morto_fw-la this_o be_v most_o true_a at_o such_o time_n as_o the_o water_n of_o fiume_n morto_fw-la be_v discharge_v into_o the_o sea_n but_o i_o do_v never_o say_v that_o thing_n can_v never_o be_v bring_v to_o that_o pass_n as_o that_o the_o level_n of_o fiume_n morto_fw-it shall_v be_v high_o than_o serchio_n and_o so_o i_o grant_v that_o it_o will_v follow_v that_o the_o water_n of_o fiume_n morto_fw-it shall_v go_v into_o serchio_n and_o it_o be_v very_o possible_a that_o the_o drain_n of_o fiume_n morto_fw-la into_o serchio_n may_v be_v continuate_a and_o i_o far_o grant_v that_o its_o possible_a that_o the_o serchio_n do_v never_o disgorge_v through_o fiume_n morto_fw-la towards_o pisa_n nay_o i_o will_v yet_o far_o grant_v that_o it_o may_v have_v happen_v that_o fiume_n morto_fw-it may_v have_v have_v such_o a_o fall_n into_o serchio_n as_o will_v have_v suffice_v to_o have_v turn_v mill_n but_o then_o i_o add_v withal_o that_o the_o plain_n of_o pisa_n and_o the_o city_n itself_o must_v be_v a_o mere_a lake_n 2._o signore_v bartolotti_n say_v confident_o that_o when_o the_o sea_n swell_v by_o the_o south-west_n or_o other_o wind_n the_o level_n of_o serchio_n in_o the_o place_n mark_v a_o in_o the_o platt_n distant_a about_o 200._o brace_n rise_v very_o little_a but_o that_o fiume_n morto_fw-la in_o d_o and_o in_o e_z many_o mile_n more_o up_o into_o land_n rise_v very_o much_o and_o that_o certain_a fisherman_n confirm_v this_o and_o show_v he_o the_o sign_n of_o the_o rise_n of_o the_o water_n i_o grant_v it_o to_o be_v very_o true_a and_o i_o have_v see_v it_o with_o my_o own_o eye_n but_o this_o come_v to_o pass_v when_o the_o mouth_n of_o fiume_n morto_fw-la be_v stop_v up_o by_o the_o sea_n as_o i_o shall_v show_v by_o and_o by_o and_o this_o rise_n near_o the_o seaside_n be_v of_o no_o considerable_a prejudice_n to_o the_o field_n and_o this_o be_v as_o much_o as_o i_o find_v to_o be_v true_a in_o the_o assertion_n of_o signore_fw-la bartolotti_n without_o his_o confirm_v it_o by_o any_o other_o proof_n as_o indeed_o it_o need_v none_o that_o the_o level_n of_o fiume_n morto_fw-la rise_v in_o e_o and_o many_o mile_n far_a upward_o it_o rise_v much_o nor_o do_v i_o ever_o affirm_v the_o contrary_n 3._o concern_v the_o difficulty_n of_o open_v the_o mouth_n of_o fiume_n morto_fw-la into_o the_o sea_n that_o which_o ill_n castellano_n say_v be_v most_o certain_a namely_o that_o at_o the_o entrance_n upon_o the_o open_n of_o the_o mouth_n it_o be_v necessary_a to_o make_v a_o deep_a trench_n but_o i_o say_v that_o at_o that_o time_n it_o be_v difficult_a to_o open_v it_o unless_o upon_o great_a occasion_n for_o that_o the_o difficulty_n proceed_v from_o the_o water_n of_o fiume_n morto_fw-la be_v low_o and_o the_o field_n drain_v 4._o as_o to_o the_o particular_a of_o the_o cause_n that_o you_o tell_v i_o man_n press_v so_o much_o unto_o the_o most_o serene_a grand_a duke_n and_o to_o the_o prince_n i_o have_v not_o much_o to_o say_v because_o it_o be_v not_o my_o profession_n nor_o have_v i_o consider_v of_o the_o same_o yet_o i_o believe_v that_o when_o the_o prince_n and_o his_o highness_n see_v the_o benefit_n of_o his_o people_n and_o subject_n in_o one_o scale_n of_o the_o balance_n and_o the_o accommodation_n of_o huntsman_n in_o the_o other_o his_o highness_n will_v incline_v to_o the_o profit_n of_o his_o subject_n such_o have_v i_o always_o find_v his_o clemency_n and_o nobleness_n of_o mind_n but_o if_o i_o be_v to_o put_v in_o my_o vote_n upon_o this_o business_n i_o will_v say_v that_o the_o point_n of_o spear_n and_o the_o mouth_n of_o gun_n the_o yelp_a of_o dog_n the_o wilynesse_n of_o huntsman_n who_o run_v thorough_a and_o narrow_o search_v all_o those_o wood_n thicket_n and_o heathe_n be_v the_o true_a destroyer_n of_o buck_n and_o boar_n and_o not_o a_o little_a salt-water_n which_o settle_v at_o last_o in_o some_o low_a place_n and_o spread_v not_o very_o far_o yet_o nevertheless_o i_o will_v not_o enter_v upon_o any_o such_o point_n but_o confine_v myself_o sole_o to_o the_o business_n before_o i_o 5._o that_o experiment_n of_o join_v together_o the_o water_n