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end_n draw_v line_n perpendicular_a 3,095 5 14.0786 5 true
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ID Title Author Corrected Date of Publication (TCP Date of Publication) STC Words Pages
A48344 Nine geometricall exercises, for young sea-men and others that are studious in mathematicall practices: containing IX particular treatises, whose contents follow in the next pages. All which exercises are geometrically performed, by a line of chords and equal parts, by waies not usually known or practised. Unto which the analogies or proportions are added, whereby they may be applied to the chiliads of logarithms, and canons of artificiall sines and tangents. By William Leybourn, philomath. Leybourn, William, 1626-1716. 1669 (1669) Wing L1925; ESTC R213612 96,458 212

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length_n of_o the_o perpendicular_a c_o a._n the_o analogy_n or_o proportion_n be_v as_o the_o sine_fw-la of_o the_o angle_n at_o c_z be_v to_o the_o log._n of_o a_o b_o so_o be_v the_o sine_fw-la of_o the_o angle_n b_o to_o the_o logar_n of_o c_o a._n or_o as_o the_o radius_fw-la be_v to_o the_o logar_n of_o a_o b_o so_o be_v the_o tangent_fw-la of_o b_o to_o the_o logar_n of_o c_o a._n case_n iu._n the_o hypotenuse_n c_o b_o 225_o the_o angle_n c_o 53_o degr_n 7_o min._n and_o the_o angle_n at_o b_o 36_o degr_n 53_o min._n give_v to_o find_v the_o base_a b_o a_o and_o the_o perpendicular_a c_o a._n draw_v a_o right_a line_n c_o b_o contain_v 225_o of_o your_o line_n of_o equal_a part_n then_o take_v 60_o deg_fw-la out_o of_o your_o line_n of_o chord_n set_v one_o foot_n of_o the_o compass_n in_o b_o and_o with_o the_o other_o describe_v the_o arch_n e_o d_o also_o the_o compass_n continue_v at_o the_o same_o distance_n place_v one_o foot_n in_o c_o and_o with_o the_o other_o 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