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Word A Word B Word C Word D Occurrence Frequency Band MI MI Band Prominent
reason_n angle_n equal_a triangle_n 2,577 5 14.6378 5 false
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ID Title Author Corrected Date of Publication (TCP Date of Publication) STC Words Pages
A80170 Navigation by the mariners plain scale new plain'd: or, A treatise of geometrical and arithmetical navigation; wherein sayling is performed in all the three kindes by a right line, and a circle divided into equal parts. Containing 1. New ways of keeping of a reckoning, or platting of a traverse, both upon the plain and mercators chart ... 2. New rules for estimating the ships way through currents, and for correcting the dead reckoning. 3. The refutation of divers errors, and of the plain chart, and how to remove the error committed thereby ... as also a table thereof made to every other centesm. 4. A new easie method of calculation for great circle-sayling, with new projections, schemes and charts ... 5. Arithmetical navigation, or navigation performed by the pen, if tables were wanting ... By John Collins of London, Pen-man, accomptant, philomathet. Collins, John, 1625-1683. 1659 (1659) Wing C5378A; Thomason E1002_1; ESTC R207824 177,819 300

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give_v i_o have_v show_v in_o a_o treatise_n entitle_v the_o sector_n on_o a_o quadrant_n page_n 139_o 140._o and_o how_o to_o find_v the_o point_n i_o or_o k_o without_o draw_v the_o line_n e_o f_o or_o o_o g_o and_o that_o by_o help_n of_o a_o cross_n or_o intersection_n like_o that_o at_o e_o which_o may_v either_o happen_v within_o or_o without_o the_o outward_a circle_n the_o reader_n may_v attain_v from_o the_o last_o scheme_n for_o find_v the_o amplitude_n the_o converse_n of_o the_o former_a scheme_n for_o find_v the_o hour_n will_v find_v the_o sun_n altitude_n on_o all_o hour_n and_o the_o distance_n of_o place_n in_o the_o arch_n of_o a_o great_a circle_n example_n latitude_n 51_o 32′_n declination_n 23_o 31′_n north._n hour_n 75_o from_o noon_n that_o be_v either_o 7_o in_o the_o morning_n or_o 5_o in_o the_o afternoon_n have_v draw_v the_o semicircle_n its_o diameter_n and_o by_o a_o perpendicular_a from_o the_o centre_n divide_v it_o into_o two_o quadrant_n and_o therein_o have_v prick_v off_o a_o l_o the_o latitude_n and_o through_o the_o same_o draw_v l_o m_o produce_v and_o parallel_v to_o d_o c_o therein_o from_o l_o to_o m_n and_o q_o prick_v off_o the_o sine_fw-la of_o the_o declination_n then_o prick_v off_o the_o hour_n from_o noon_n from_o a_o to_o r_n and_o lay_v the_o ruler_n from_o the_o centre_n draw_v the_o line_n r_o e_o and_o with_o the_o cousin_a of_o the_o declination_n namely_o the_o near_a distance_n from_o f_o to_o d_o c_o draw_v the_o arch_n g_o e_o and_o transfer_v the_o distance_n between_o the_o point_n m_o and_z e_z from_o m_n to_o h._n last_o the_o distance_n between_o the_o point_v n_n and_o h_n be_v the_o chor●_n of_o the_o sun_n distance_n from_o the_o zenith_n for_o that_o hour_n namely_o 62_o 37′_n the_o compliment_n whereof_o 27_o 23′_n be_v the_o altitude_n seek_v moreover_o the_o distance_n between_o h_n and_o q_n be_v the_o chord_n of_o the_o sun_n distance_n from_o the_o zenith_n for_o the_o winter_n declination_n namely_o 99_o 30′_n which_o be_v great_a than_o a_o quadrant_a argue_v the_o sun_n to_o have_v 9_o 30′_n of_o depression_n under_o the_o horizon_n and_o so_o much_o be_v his_o altitude_n for_o the_o hour_n of_o 5_o in_o the_o morning_n or_o 7_o in_o the_o afternoon_n when_o his_o declination_n be_v 23_o 31′_n north._n another_o example_n for_o the_o same_o latitude_n and_o declination_n let_v the_o hour_n from_o noon_n be_v either_o 10_o in_o the_o morning_n or_o 2_o in_o the_o afternoon_n prick_v off_o 30_o from_o a_o to_o k_o and_o from_o the_o centre_n draw_v the_o line_n k_o g_o place_z the_o distance_n m_o g_z from_o m_n to_o o_o so_o be_v the_o distance_n o_o n_n the_o chord_n of_o 36_o 16′_n the_o compliment_n whereof_o 53_o 44′_n be_v the_o summer_n altitude_n for_o that_o hour_n and_o the_o distance_n o_fw-fr qui_fw-fr be_v the_o chord_n of_o 79_o 32′_n the_o compliment_n whereof_o 10_o 28′_n be_v the_o winter_n altitude_n for_o that_o hour_n also_o for_o the_o distance_n of_o place_n in_o the_o ark_n of_o a_o great_a circle_n the_o case_n in_o spherical_a triangle_n be_v the_o same_o with_o that_o here_o resolve_v so_o if_o there_o be_v two_o place_n the_o one_o in_o north_n latitude_n 51_o 32′_n the_o other_o in_o north_n latitude_n 23_o 31′_n the_o difference_n of_o longitude_n between_o they_o be_v 75_o their_o distance_n by_o the_o former_a scheme_n will_v be_v find_v to_o be_v 62_o 37′_n but_o if_o the_o latter_a place_n be_v in_o as_o much_o south_n latitude_n than_o their_o distance_n will_v be_v 99_o 30′_n another_o example_n for_o find_v the_o distance_n of_o place_n in_o the_o arch_n of_o a_o great_a circle_n example_n let_v the_o two_o place_n be_v according_a to_o the_o seaman_n calendar_n isle_n of_o lobos_n longitude_n 307_o 41′_n latitude_n 40_o 21′_n south_n lizard_n 18_o 30._o latitude_n 50_o 10_o north._n difference_n of_o longitude_n 289_o 11._o compliment_n 70_o 49′_n have_v describe_v a_o circle_n make_v ae_n m_o 70_o 49′_n m_o i_o the_o latitude_n of_o the_o island_n b_o i_o the_o sine_fw-la thereof_o fall_v perpendicular_o on_o c_o m_n ae_n l_o the_o latitude_n of_o the_o lizard_n l_o a_o the_o sine_fw-la thereof_o make_v a_o e_o equal_a to_o the_o extent_n a_o b_o and_o prick_v b_o i_o from_o l_o upward_o to_o h_n when_o the_o place_n be_v in_o different_a hemisphere_n but_o downward_o to_o k_o when_o in_o the_o same_o hemisphere_n and_o the_o extent_n h_o e_o or_o k_n e_o be_v the_o chord_n of_o the_o ark_n of_o distance_n between_o both_o place_n in_o this_o example_n h_o e_z be_v 109_o 41′_n k_o e_z be_v 48_o 57′_n demonstration_n this_o scheme_n i_o first_o meet_v with_o in_o a_o map_n make_v in_o holland_n the_o foundation_n whereof_o be_v long_o since_o lay_v by_o copernicus_n and_o regiomontanus_n who_o from_o a_o right_n line_v plain_a triangle_n happen_v at_o the_o centre_n of_o the_o sphere_n have_v prescribe_v a_o method_n of_o calculation_n for_o find_v a_o angle_n when_o three_o side_n be_v give_v here_o we_o shall_v illustrate_v the_o converse_n how_o from_o two_o side_n and_o the_o angle_n comprehend_v to_o find_v the_o three_o side_n from_o any_o two_o point_n in_o the_o sphere_n suppose_v perpendicular_o to_o fall_v on_o the_o plain_a of_o the_o equator_fw-la here_o represent_v by_o ae_n l_o q_o m_o which_o perpendicular_o be_v the_o sin_n of_o the_o latitude_n of_o those_o two_o point_n and_o the_o distance_n of_o the_o point_n in_o the_o plain_a of_o the_o equinoctial_a from_o the_o centre_n of_o the_o sphere_n be_v the_o cosines_n of_o those_o latitude_n &_o the_o angle_n at_o the_o centre_n between_o those_o point_n in_o the_o plain_a of_o the_o equator_fw-la be_v equal_a to_o the_o arch_n of_o the_o equinoctial_a between_o the_o two_o meridian_n pass_v through_o the_o suppose_a point_n in_o the_o sphere_n now_o a_o right_a line_n extend_v in_o the_o sphere_n between_o any_o two_o point_n be_v the_o chord_n of_o the_o ark_n of_o distance_n between_o those_o point_n understand_v then_o that_o the_o three_o point_n a_o c_o b_o limit_v the_o side_n of_o a_o righ●_n line_v triangle_n in_o the_o plain_a of_o the_o equator_fw-la whereof_o the_o angle_n a_o c_o b_o be_v at_o the_o centre_n than_o the_o extent_n a_o b_o be_v place_v from_o a_o to_o e_o if_o then_o we_o draw_v d_o e_o g_o perpendicular_a to_o a_o q_o and_o place_n b_o i_o from_o e_z to_z g_z and_o d_o the_o extent_n l_o g_o shall_v be_v the_o chord_n of_o the_o three_o side_n when_o the_o place_n be_v in_o different_a hemisphere_n and_o the_o extent_n l_o d_o be_v the_o chord_n of_o their_o distance_n when_o they_o be_v in_o the_o same_o hemisphere_n and_o if_o the_o extent_n e_o d_o e_o g_o be_v place_v from_o l_o to_o h_n and_o k_n the_o line_n d_o e_o g_o need_v not_o be_v draw_v because_o the_o extent_n l_o g_o and_o l_o d_o if_o it_o be_v right_o conceive_v be_v the_o two_o very_a point_n at_o first_o suppose_v in_o the_o sphere_n the_o extent_n a_o b_o as_o to_o 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declination_n and_o right_a ascension_n divers_a other_o scheme_n from_o other_o proportion_n may_v be_v add_v for_o find_v the_o hour_n and_o azimuth_n etc._n etc._n which_o which_o i_o be_o loath_a to_o trouble_v the_o reader_n withal_o i_o shall_v add_v another_o scheme_n for_o this_o purpose_n which_o carry_v on_o the_o same_o proportion_n by_o which_o this_o case_n be_v usual_o calculate_v the_o proportion_n be_v express_v in_o a_o treatise_n the_o sector_n on_o a_o quadrant_n page_n 127._o example_n latitude_n 51_o 32′_n declination_n 23_o 31._o hour_n 60_o from_o noon_n have_v draw_v a_o semicircle_n and_o the_o radius_fw-la z_o d_o prick_v the_o latitude_n from_o c_o to_o l_o
which_o snellius_n assert_n be_v that_o the_o tangent_fw-la cut_v off_o to_o wit_n i_o b_o be_v somewhat_o short_a than_o the_o arch_n i_o a_o though_o near_o it_o in_o length_n when_o the_o arch_n be_v not_o above_o 1_o 12_o part_n of_o a_o quadrant_n and_o this_o hugenius_n demonstrate_v in_o his_o book_n de_fw-fr magnitudine_fw-la circuli_fw-la where_o he_o find_v fault_n with_o snellius_n his_o demonstration_n thereof_o now_o the_o proportion_n for_o find_v a_o angle_n raise_v from_o that_o scheme_n lie_v thus_o as_o r_n e_o the_o sum_n of_o the_o double_a of_o the_o hipotenusal_a c_o a_n and_o of_o the_o side_n c_o e_o be_v to_o e_o a_o the_o lesser_a side_n ∷_o so_n be_v r_n i_o the_o triple_a of_o the_o radius_fw-la or_o hipotenusal_a ∷_o to_z i_o b_o the_o length_n of_o the_o arch_n require_v ∷_o propé_fw-fr verum_fw-la this_o proportion_n find_v the_o length_n of_o the_o arch_n make_v the_o hipotenusal_a always_o radius_fw-la whereas_o in_o calculation_n we_o always_o retain_v such_o a_o radius_fw-la whereof_o the_o circumference_n of_o the_o circle_n be_v 360_o now_o the_o diameter_n of_o such_o a_o circle_n will_v be_v find_v by_o the_o number_n in_o page_n 112_o in_o which_o the_o proportion_n of_o the_o circumference_n to_o the_o diameter_n be_v express_v to_o be_v 114_o 5915_o wherefore_o the_o radius_fw-la of_o such_o a_o circle_n be_v 57_o 2957_o and_o the_o triple_a thereof_o be_v 171_o 8871_o then_o retain_v the_o two_o first_o term_n of_o the_o former_a proportion_n we_o may_v make_v this_o number_n the_o thy_o d_o term_n and_o by_o one_o single_a work_n find_v the_o angle_n or_o rather_o take_v the_o half_n of_o all_o four_o term_n the_o proportion_n will_v hold_v as_o the_o sum_n of_o the_o hipotenusal_a and_o of_o half_a the_o great_a leg_n of_o a_o plain_a right_a angle_a triangle_n be_v to_o the_o lesser_a leg_n thereof_o ∷_o so_n be_v 86_o to_o the_o angle_n oppose_v to_o the_o lesser_a leg_n the_o half_a of_o 171_o 8871_o be_v 85_o 9435_o which_o because_o we_o have_v take_v it_o to_o be_v 86_o the_o proportion_n if_o the_o angle_n be_v less_o than_o 30_o find_v the_o angle_n to_o be_v about_o one_o centesimal_n part_n of_o a_o degree_n too_o much_o but_o if_o the_o angle_n be_v above_o 35_o by_o reason_n the_o scheme_n be_v not_o absolute_o true_a must_v have_v these_o addition_n make_v to_o the_o angle_n find_v thereby_o from_o 35_o to_o 38_o add_v one_o centesm_n from_o 38_o to_o 40_o add_v two_o centesme_n to_o it_o and_o afterward_o to_o 45_o for_o every_o degree_n it_o exceed_v 40_o add_v one_o centesm_n more_o beside_o the_o former_a two_o centesm_n and_o thus_o we_o may_v always_o find_v the_o lesser_a acute_a angle_n and_o consequent_o the_o great_a be_v the_o compliment_n thereof_o within_o one_o centesm_n of_o the_o truth_n which_o be_v near_o than_o any_o mechanic_n way_n example_n in_o the_o former_a triangle_n let_v there_o be_v give_v the_o side_n c_o e_z 4_o 17_o a_o e_z 3_o 93_o by_o extract_v the_o square_a root_n of_o the_o sum_n of_o the_o square_n of_o these_o two_o number_n we_o shall_v find_v the_o side_n c_o a_o to_o be_v 5_o 73_o to_o which_o add_v the_o half_a of_o c_o e_o the_o sum_n be_v 782_o the_o divisor_n then_o multiply_v 393_o the_o lesser_a leg_n by_o 86_o the_o product_n be_v 33798_o to_o which_o you_o may_v annex_v cipher_n at_o pleasure_n to_o find_v the_o decimal_a part_n of_o a_o degree_n and_o divide_v by_o 782_o you_o will_v find_v the_o quotient_a to_o be_v 43_o 22_o centesme_n to_o which_o if_o you_o add_v 5_o centesme_n error_n the_o angle_n seek_v be_v 43_o 27_o centesm_n ready_o to_o find_v what_o allowance_n must_v be_v make_v in_o respect_n of_o the_o arch_n find_v you_o may_v repair_v to_o a_o table_n of_o natural_a sin_n and_o take_v the_o two_o leg_n of_o the_o right_a angle_a triangle_n to_o be_v the_o sine_fw-la and_o cousin_n of_o any_o arch_n and_o by_o the_o last_o proportion_n find_v how_o near_o you_o can_v recover_v the_o arch_n again_o whereby_o you_o will_v find_v what_o allowance_n must_v be_v make_v the_o example_n here_o use_v be_v that_o mention_v in_o page_n 16_o and_o 109_o so_o that_o hereby_o we_o find_v a_o course_n and_o distance_n on_o the_o plain_a chart_n without_o the_o help_n of_o table_n and_o by_o the_o like_a reason_n the_o height_n of_o a_o gnomon_n and_o the_o length_n of_o its_o shadow_n be_v give_v the_o sun_n height_n may_v be_v get_v without_o table_n hugenius_n not_o think_v this_o way_n of_o snellius_n to_o be_v exact_a enough_o propound_v another_o of_o his_o own_o upon_o this_o consideration_n that_o the_o chord_n of_o a_o arch_n be_v increase_v by_o one_o three_o part_n of_o the_o difference_n between_o the_o sine_fw-la and_o the_o chord_n of_o the_o say_a arch_n shall_v be_v very_o near_o equal_a in_o length_n to_o the_o arch_n itself_o yea_o so_o near_o that_o in_o a_o arch_n of_o 45_o it_o shall_v not_o err_v or_o fall_v short_a above_o 1_o 18000_o part_n of_o a_o degree_n and_o in_o a_o arch_n of_o 30_o not_o above_o the_o 1_o 21600_o part_n of_o a_o degree_n whereby_o the_o sin_n may_v be_v examine_v and_o a_o angle_n find_v without_o table_n as_o if_o the_o side_n of_o the_o former_a triangle_n be_v give_v by_o take_v c_o e_o out_o of_o c_o a_o there_o remain_v e_z i_o the_o square_a whereof_o add_v to_o the_o square_n of_o e_o a_o the_o sine_fw-la be_v equal_a to_o the_o square_n of_o the_o line_n a_o i_o the_o chord_n whereby_o may_v be_v find_v the_o length_n of_o the_o arch_n i_o a_o to_o the_o give_v radius_fw-la c_o a_o and_o then_o by_o another_o proportion_n the_o measure_n of_o the_o say_a arch_n to_o the_o radius_fw-la of_o such_o a_o circle_n who_o circumference_n be_v 360d._o in_o like_a manner_n if_o the_o side_n of_o a_o oblique_a plain_a triangle_n be_v give_v the_o angle_n thereof_o may_v be_v find_v if_o you_o first_o reduce_v that_o oblique_a triangle_n to_o two_o right_a angle_a plain_a triangle_n which_o be_v perform_v in_o every_o book_n of_o trigonometry_n without_o table_n but_o for_o such_o case_n of_o plain_a triangle_n in_o which_o but_o one_o side_n with_o two_o angle_n be_v give_v to_o find_v the_o other_o side_n in_o regard_n the_o proportion_n for_o such_o case_n require_v sin_n and_o that_o we_o have_v not_o attain_v any_o ready_a way_n to_o make_v the_o sine_fw-la of_o any_o arch_n at_o command_n forbear_v to_o mention_v such_o way_n as_o be_v both_o troublesome_a and_o uncertain_a we_o must_v suppose_v that_o the_o reader_n be_v furnish_v with_o a_o table_n of_o sines_n which_o most_o mariner_n have_v in_o their_o seaman_n calendar_n finis_fw-la errata_fw-la page_n 1_o line_n 31_o for_o will_v read_v shall_v p._n 48._o l._n 30._o for_o 48_o degree_n r._n 84_o degree_n p._n 49_o l._n 3._o for_o angle_n r_o angle_n l._n 4_o for_o sine_fw-la r._n line_n p._n 51._o l._n 25._o for_o follow_a r_o former_a p._n 59_o l._n 14._o for_o or_o r._n of_o p._n 60._o l._n 21._o for_o as_o every_o r._n or_o ever_o p._n 81_o l._n 16._o for_o one_o be_v r._n one_o in_o page_n 88_o l._n 26._o for_o tangent_fw-la r._n tangent_n a_o table_n of_o meridional_a part_n d_o 0_o 1_o 2_o 3_o 4_o 5_o 6_o 7_o 8_o 9_o 0_o 0_o 000_o 1_o 000_o 2_o 000_o 3_o 001_o 4_o 003_o 5_o 006_o 6_o 011_o 7_o 017_o 8_o 02●_n 9_o 037_o 2_o 020_o 020_o 2_o 020_o 0●1_n 023_o 029_o 031_o 037_o 046_o 057_o 4_o 040_o 040_o 04●_n 041_o 043_o 046_o 051_o 057_o 066_o 077_o 6_o 060_o 060_o 060_o 061_o 063_o 066_o 071_o 077_o 086_o 097_o 8_o 080_o 080_o 080_o 081_o 083_o 086_o 091_o 097_o 106_o 117_o 10_o 100_o 1_o 100_o 2_o 100_o 3_o 101_o 4_o 103_o 5_o 106_o 6_o 111_o 7_o 118_o 8_o 127_o 9_o 138_o 12_o 120_o 120_o 120_o 121_o 123_o 126_o 131_o 138_o 147_o 158_o 14_o 140_o 140_o 140_o 141_o 143_o 146_o 151_o 158_o 167_o 178_o 16_o 160_o 160_o 160_o 161_o 163_o 166_o 171_o 178_o 187_o 198_o 18_o 180_o 180_o 180_o 181_o 183_o 186_o 191_o 198_o 207_o 218_o 20_o 200_o 1_o 200_o 2_o 200_o 3_o 201_o 4_o 204_o 5_o 207_o 6_o 212_o 7_o 219_o 8_o 228_o 9_o 239_o 22_o 220_o 220_o 220_o 221_o 224_o 227_o 232_o 239_o 248_o 259_o 24_o 240_o 240_o 240_o 241_o 244_o 247_o 252_o 259_o 268_o 279_o 26_o 260_o 260_o 260_o 261_o 26●_n 267_o 272_o 279_o 288_o 300_o 28_o 280_o 280_o 280_o 281_o 284_o 287_o 292_o 299_o 308_o 320_o 30_o 300_o 1_o 300_o 2_o 300_o 3_o 301_o 4_o 304_o 5_o 307_o 6_o 312_o 7_o 319_o 8_o 329_o 9_o 341_o 32_o 320_o 320_o 320_o 321_o 324_o 327_o 332_o 339_o 349_o 361_o 34_o 340_o 340_o 340_o 341_o 344_o 347_o 352_o