The elements of navigation : containing the theory and practice, with all the necessary tables, to which is added, a treatise of marine fortification ... (1754)
Robertson, J. (John), 1712-1776, Adams, Charles Francis, 1807-1886, former owner. BRL, Adams, John, 1735-1826, former owner. BRL, Boston Public Library) John Adams Library BRL · London : Printed for J. Nourse ... · leaf 72
167. PROBLEM. Xtl. To three given right lines a, b, c, to find d a fourth proportional. Operation, ift. Draw two right lines mak- A- - ing any angle, and meeting in a. 2d. In thefe lines take a b — firft term, a c ■=. fe-cond term, and ad = third term. 3d. Draw b c, and parallel thereto thro d… … * And is thus read, ah is to ac fo is ad to ae.The firft ; ftands for is to, the laft : for to, and : : for/a is. H2 16?. §2 GEOMETRY. -A
Navigation · Nautical astronomy · Fortification
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![An illustration from Nicolai Copernici Torinensis De reuolutionibus orbium coelestium, libri VI : Habes in hoc opere iam recens nato, & aedito, studiose lector, motus stellarum, tam fixarum, quàm erraticarum, cum ex ueteribus, tum etiam ex recentibus obseruationibus restitutos: & nouis insuper ac admirabilibus hypothesibus ornatos. Habes etiam tabulas expeditissimas, ex quibus eosdem ad quoduis tempus quàm facillime caculare poteris. Igitur eme, lege, fruere. [Line in Greek] (1543)](https://img.insideoutlibrary.com/img/200/ia-nicolaicopernici00cope-271-175.webp)
