Recreations in astronomy : with directions for practical experiments and telescopic work (1879)
Warren, Henry White, 1831-1912 · New York : Harper & Brothers · leaf 113
ard the sun, as shownin ¥\^ 87. The rye-piece should be drawn out ahout half an inch be- 96 A SOLAR SYSTEM yond its usual focusing for distant objects. The farther it is drawn, thenearer must we hold the screen for a perfect image. By holding a paper near the eye-piece, the proper direction of the… … Fig. 37.—Holding Telescope to see the Snus Spots. First covering the eyes with very dark or smoked glasses, erect a di>kof pasteboard four inches in diameter between you and the sun; (one eye; stand near it, and the whole sun is obscured. Withdraw fromit till the suns rays just shoot over the…
Astronomy
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