The first six books of the elements of Euclid, in which coloured diagrams and symbols are used instead of letters for the greater ease of learners (1847)
Byrne, Oliver, Whittingham, Charles, 1795-1876, Chiswick Press · London : William Pickering · leaf 162
fcribe a circle. Bifeft ^ and ^V. (B. i.pr. 9.) byand —^^ from the point where thefe linesmeet draw -•■■—,and »•••■ refpedlively per-pendicular to —BMI^HiB , … In and / and > A 4 and common, ,*, «••••••.•. ^^ .■■■...•.». (B. i. pr. 4and 26.) In like manner, it may be fhown alfo that hence with any one of thefe lines as radius, defcribe and it will pafs through the extremities of the o other two; and the fides of the given triangle, being per-pendicular…
Euclid's Elements · 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-151-85.webp)
