A high-school astronomy: in which the descriptive, physical, and practical are combined .. (1853)
Mattison, Hiram, 1811-1868 · New York, F. J. Huntingdon [etc.] · leaf 226
ld be very difficult to direct such a telescope towardcelestial objects, or to get the eye in the focus after it was thus directed. 516. The Galilea/h telescope consists of two glasses—a double-convex next the object, and a double-concavenear the eye. The former converges the light till it canbe… … Here the light is converged by the lens A, till it can be received by the double-con-cave lens B, by which the rays are made to become a small parallel beam, that can enterthe eye at C. This was the form of the telescope constructed by Jansen, and improvedby Galileo; on which account it is called…
Astronomy
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