DECLINATION, in Astronomy, the distance of any celestial object from the equinox, either northward or southward. It is either true or apparent, according as the real or apparent place of the object is considered.

DECLINATION of the Sea Compass or Needle, is its variation from the true meridian of any place.

DECLINATION of a Plane or Wall, in Dialing, is the ho-

horizontal arch contained between the plane and the prime vertical circle, reckoning from east to west, or between the meridian and the plane, reckoning from north to south. Many ways are used for finding this declination, but the most easy and practicable is by a declinator.