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PARALLELS of Latitude, in Astronomy, are lesser circles of the sphere, parallel to the ecliptic, and imagined to pass through every degree and minute of the colures.

PARALLELS of Altitude, or Alticentars, are circles parallel to the horizon, imagined to pass through every degree and minute of the meridian between the horizon and zenith, and having their poles in the zenith.

PARALLELS of Declination, in Astronomy, are the same with parallels of latitude in geography.