Young, Charles A. (Charles Augustus), 1834-1908, Young, Anne Sewell, b. 1871., ed · Boston, New York [etc.] Ginn and Company · leaf 25
while OB is the line drawn to the visible horizon. The visible horizon, therefore, is not a great circle of thecelestial sphere, but technically a small circle, parallel to the truehorizon and depressed below it by an amount measured by theangle HOB, which is called the Dip of the Horizon.1 In… … Fig. 3. — Dip of the Horizon. 1 The Dip (in minutes) = y/h (in feet) nearly. 12 VERTICAL CIRCLES. [§16 sextant the height of the sun or other heavenly body, in theoperations by which he determines the place of his ship. 17. Vertical Circles; the Meridian and the Prime Vertical.— Vertical Circles…
Astronomy · Constellations
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