22 N 46 N 2 N

* These are the principal fixed stars, near the ecliptic, to which only the planets can approach. If the student require the places of the stars for the purpose of bringing them to the midheaven or ascendant in a nativity, he may learn their right ascension and declination in the Nautical Almanac for each year, and he may readily calculate their longitudes and latitudes therefrom by the rules we have given.

N.B. The longitudes increase about 50" J each year; the latitudes do not vary.

Rules to find the Zodiacal Latitude and Longitude of a Fixed Star, Comet, Planet, or the fyc. from the Bight Ascension and Declination.

1st. If the right ascension be less than 180°, it is north; and if it be more than 180*, it is south.'

2d. To the logarithm co-tangent of the declination add the logarithm sine of the right ascension, measured from T or ; but if measured from s or Vf, the logarithm co-sine: the sum (minus 10 in the Index), will be the log. tangent of the angle A.

3d. If the right ascension and declination be both north, or both south, add 23° 28' to angle A, and it will give angle B.

4th. If the right ascension and declination be one north and the other south, the difference between 23° 28' and angle A will give angle B.

Note.—If angle B exceed 90°, the latitude will be of the contrary name to the declination; but if angle B be less than 90°, the latitude will be of the same name as the declination.

To find the Longitude. To the arithmetical comp. of the log. sine of angle A, and the log. sine of angle B, add the log. tang, of R.A. from T or (or the log. co-tang of R.A. from s or Vf). The sum will be the log. tang, of the longitude from r or or the log. co-tang. of the longitude from © or yp.

To find the Latitude. To the arithmetical comp. of the log. co-sine of angle A, and the log. co-sine of angle B, add the log. sine of the decimation. The sum will be the log. sine of the latitude.

N.B. The arithmetical complement of a logarithm is found by subtracting it from . . . 10.00000

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