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 61
■^■■■- is greater than the other; and .*. they are equal; and 4 = 4, (pr. 4.). CASE II.Again, let ^——• ^ ■——— ^ which lie oppofite the equal angles flik and ^^^. If it be poflible, let Then in ^ and J^^^ we have = and /^ = J^, Iut H^ = JBi^ (hyp.).*. jf^ = ^^^ which is abfurd (pr. 16.).… … F ajlralght line ( ) meet- i?2g tivo other Jiraight lines, - and ) makes with them the alternate angles (
Euclid's Elements · Geometry
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![An illustration from Lo presente libro insegna la vera arte delo excelle[n]te scriuere de diuerse varie sorti de litere : le quali se fano p[e]r geometrica ragione & con la presente opera ognuno le potra imparare impochi giorni p[er] lo amaistramento, ragione, & essempli, come qui seguente vederai (1544)](https://img.insideoutlibrary.com/img/200/ia-gri_33125008713881-38-1.webp)
