Horologium oscillatorium, sive de motu pendulorum ad horologia aptato demonstrationes geometricae
$95,000 · Offered by Sophia Rare Books
First edition
Paris: François Muguet, 1673. / First edition, a fine copy, of “the most original work of this kind since Galileo's Discorsi” PMM and “second in scientific importance perhaps only to Newton's Principia, which is in some respects based on it” Singer . Huygens proves that the tautochrone is the cycloid, shows that the evolute of a cycloid is another cycloid, applies both results to a cycloidally
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