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 269
t ^mmmmi^m and —-^— may be in the lameftraight line. Whence alfo i and -aiM^MMM mull be in the fame ftraight line. (B. i. pr. 14.) Draw ■——— , then > (B. 6. pr. I.) (B. 5. pr. 7.) (B. 6. pr. I.) BOOK VI. PROP. XV. THEOR. 235 > (B. 5. pr. II.) II. Let the fame conftruction remain, and (B. 6.… … : ■■). !■>..._..) contaifiedby the extremes, is equal to the rectangleX .........) contained by the means. PART II. And if the reSt-angle contained bythe extremes be equalto the reBangle con-tained by the means,the fourJlraight linesare proportional. PART I.From the extremities of •—i» and…
Euclid's Elements · Geometry
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