American practical navigator: an epitome of navigation and nautical astronomy (1914)
Bowditch, Nathaniel, 1773-1838, United States. Navy Dept. Bureau of Equipment, Logan, George Wood, 1868-1915 · Washington, Govt. Print. Off. · leaf 130
me. A very satisfactory methodis to set the sextant in advance at definite intervals of altitude and note the time ascontact is observed. 319. Correct the observed altitude for instrumental and other errors, reducingthe apparent to the true altitude. If the sun, the moon, or a planet is observed,… … mean time of observation with a fair decree of accuracy, the first hour angle foundwill be an approximate one; the declination corrected by this new value of the timewill produce a more exact value of the hour angle, and the operation may be repeateduntil a sufficiently precise value is determined.…
Navigation · Nautical astronomy
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