The Elements of Euclid : viz. the first six books, together with the eleventh and twelfth : the errors, by which Theon, or others, have long ago vitiated these books, are corrected, and some of Euclid's demonstrations are restored : also, the book of Euclid's Data, in like manner corrected (1806)
Euclid, Simson, Robert, 1687-1768, Euclid. Elements. Book 11-12. English. 1806, Euclid. Data. English. 1806, Simson, Robert, 1687-1768. Notes, critical and geometrical. 1806, Simson, Robert, 1687-1768. Elements of plane and spherical trigonometry. 1806 · Philadelphia : Published by Mathew Cary, and sold by J. Conrad & Co., S.F. Bradford, Birch & Small, and Samuel Etheridge, printed by T. & G. Palmer ... · leaf 85
4.1.EBA is equal to the angle EDF : but EDF is a right angle,wherefore EBA is a right angle : and EB is drawn from the *»>centre : but a straight line diawn from the extremity of adiameter, at right angles to it, touches the circle^: thereforedCor. 16AB touches the circle ; and it is drawn from… … PROP. XVIII. THEOR. IF a Straight line touches a circle, the straight linedrawn from the centre to the point of contact shallbe perpendicular to the line touching the circle. Let the straight line DE touch the circle ABC in the pointC ; take the centre F, and draw the straight line FC : FC is…
Euclid's Elements · Mathematics, Greek · Geometry
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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-298-193.webp)
