A high-school astronomy: in which the descriptive, physical, and practical are combined .. (1859)
Mattison, Hiram, 1811-1868 · New York, Mason brothers · leaf 237
ted the construction of reflecting telescopes. 532. The Newtonian Reflector is so called after SirIsaac Newton, its inventor. Instead of a concave mir-ror in the focus of the speculum, he placed a plane inir- 531. How many kinds of reflectors ? Describe the Gregorian. (Diagram.Why mlled Gregorian… … The light from the speculum is here shown falling upon the inclined mirror in thecenter, and reflected out to the eye of the observer. 533. The Cassegranian Rpflector is so called from M.Cassegrain, its inventor. It resembles the Gregorian,except that the speculum placed in the focus of the…
Astronomy
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