The geography of the heavens, and class-book of astronomy: (1858)
Burritt, Elijah H. (Elijah Hinsdale), 1794-1838, Mattison, Hiram, 1811-1868 · New York, Mason brothers · leaf 324
supposed to be off on the right, in the direction towardswhich the instrument is pointed. It is called a Gregorian telescope, after Mr. JamesGregory, who first suggested the construction of reflecting telescopes. T05. The Newtonian Reflector is so called after Sir IsaacNewton, its inventor. Instead… … The light from the speculum is here shown falling upon the inclined mirror in the cen-ter, and reflected out to the eye of the observer. 106. The Cassegranian Reflector is so called from M. Casse-grain, its inventor. It resembles the Gregorian, except that thespeculum placed in the focus of the…
Constellations · Stars
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