The American practical navigator : being an epitome of navigation and nautical astronomy (1888)
Bowditch, Nathaniel, 1773-1838, United States. Navy Dept. Bureau of Navigation, Cooper, Philip Henry, 1844-1912 · Washington : Govt. Print. Off. · leaf 100
NAUTICAL ASTRONOMY. 67 … 1—ALTITUDE AND AZIMUTH. Alt. 166. In this system the primary circle is the Jiorizon. An observer in changing his position on the, surface of the earth changes his zenith, but the pole of the heavens remains fixed ; hence, the object of this systemis to connect the zenith with the fixed pole, by…
Navigation · Nautical astronomy
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