Padua: Paolo Frambotto, 1649. 8vo. [viii], 80 pp. THIRD EDITION. With a large folding engraved plate of the sector and numerous woodcut text diagrams. Early soft boards; a superb copy from the library of Felix and Frieda Pollak, with their bookplate. Preserved in a folding cloth box. Item #13842
Third edition of Galileo’s valuable first published book. He here describes and explains the use of his invention, the geometric and military compass, or circle of proportion. The instrument, the first important device to perform arithmetical calculations by mechanical means, made it possible to calculate the ratios between linear dimensions of planar and solid bodies, and was specifically created to calculate trajectories and distances for military purposes. According to DSB, Galileo “transformed [the device] from a simple device of limited use to an elaborate calculating instrument of varied uses and of great practical utility by adding to it a number of supplementary scales. He . . . wrote a treatise on its use for engineers and military men.”
Pollak (1909-1987), an Austrian émigre, became an accomplished American poet and special collections curator at the University of Wisconsin.