Quadratum geometricum

by Georg Peuerbach

$18,500 · Offered by Sophia Rare Books

First edition

Nuremberg: Johann Stuchs, 1516. First edition, the Otto Schäfer copy, of one of Peuerbach’s rarest works: the treatise in which he standardised the geometric square and printed, for the first time, a table of arctangents. Peuerbach wrote it in 1455; it did not reach print until 1516. The instrument it describes, a square frame with a sighting rule, fills the title-page in a full-page woodcut and became a widely used

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