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 297
Jide (-^^—•) produced, that whole produced fide ( ■■•), and its external fegment (——--—) will be proportional to thefides (-^——■..— and ), which contain the angle adjacent to the external bifeSled angle. For if I be drawn || -.---»•»■• ^ then ^^ = \ / , (B. i. pr. 29); and = ^,(hyp-). = ^P, (B. I.… … X
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-42-20.webp)