Lessons in astronomy including uranography. A brief intoductory course without mathematics (1896)
Young, Charles A. (Charles Augustus), 1834-1908 · Boston, London, Ginn and company · leaf 126
nd light ofthe sun are so intense that we cannot look directly at it witha telescope, as we do at the moon,and it is necessary, therefore, toprovide either a special eye-piecewith suitable shade-glass, or arrangethe telescope, as in Fig. 27, so as tothrow an image of the sun upon ascreen. In the… … 116 GREAT SUN SPOT. [§164 operations, since an object-glass which would give admirableresults for visual purposes would be worthless photograph-
Astronomy
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