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 175
pO dcfirihc j r.-TiV chcn: s grom egh:.s: sJ ^nd csiii oik and ^^ Bilect ^JHk andbT ••••••»»»«» and ..-•...... , and ^om the point of fedion, draw ._^B, >••»»• , and ^^^^. (B. i.pr.6): … I like manner it mar be proved that■ ^ ^iB^^M ^ ^^——, andtherefore -••••••• ^ —^— ^ ••m>»...w. Therefore if a circle be defcribed from the point wherethefe five lines meet, with any one of tfaem as a radius, it will circumicribe the given pcntagoo. Q E- D.
Euclid's Elements · Geometry
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![An illustration from Cosmographia in qvatvor libros distribvta summo ordine, miraqve facilitate, ac breuitate ad magnam Ptolemæi mathematicam constructionem, ad vniuersamque astrologiam institutens. Francisco Barocio ... avtore. Cum præfatione eiusdem autoris, in qua perfecta quidem astrologiæ diuisio, & enarratio autorum illustrium, & voluminum ab eis conscriptorum in singulis astrologiæ partibus habetur: Joannis de Sacrobosco verò 84 errores, et alij permulti suorum expositorum, & sectatorum ostenduntur. rationibusq[uam] redarguuntur. Præcesserunt etiam quædam communia mathematica, necnon arithmetica, & geometrica principia, nonnullæq[uam] propositiones, de quibus in toto opere sæpe fit mentio: ac demum locupletissimus index eorum, quæ ipsa Cosmographia continentur .. (1585)](https://img.insideoutlibrary.com/img/200/ia-cosmographiainqv00baro-107-30.webp)
