... thinge, a great distance, and specyally by the ayde of other glasses. [Here we have the principle of the Refracting Telescope.] . . . the smallest sorte of them, commonly called spectacle glasses . . . ys grounde vppon a toole of Iron, made of purpose,...
Descartes and the Hyperbolic Quest: Lens Making Machines and Their ... - Page 13
by D. Graham Burnett - 2005 - 152 pages
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