A system of experimental philosophy prov'd by mechanicks [Microform] : wherein the principles and laws of physicks, mechanicks, hydrostatiks, and optiks, are demonstrated and explained at large by a great number of curious experments ... / as performed by J.T. Desaguliers ; to which is added Sir Isaac Newton's Colours ; the description of the condensing engine, with its apparatus ; and Royley's Horary, a machine representing the motion of the moon about the earth, Venus and Mercury about the Sun, according to the Copernian system