An introduction to astronomy : designed as a text book for the students of Yale College (1846)
Olmsted, Denison, 1791-1859, Yale College (1718-1887) · New York : Collins, Brother & Co. · leaf 77
s, two on eachside of the central wire, and allat equal distances from eachother, as is represented in thefollowing diagram. The timeof arriving at each of the wiresbeing noted, and all the timesadded together and divided bythe number of observations, theresult gives the instant of cross-ing the… … ASTRONOMICAL INSTKUMENTS. 53 on its axis ; that is, it is regulated to sidereal time. It measuresthe progress of a star, indicating an hour for every 15°, and 24hours for the whole period of the revolution of the star. Siderealtime, it will be recollected, commences when the vernal equinoxis on the…
Astronomy
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