in astronomy, an arch of the horizon, intercepted between the meridian of the place and the azimuth, or vertical circle passing through the centre of the object, which is equal to the angle of the zenith, formed by the meridian and vertical circle; or it is found by this proportion, as the radius to the tangent of the latitude of the place, so is the tangent of of the sun's or star's altitude, for instance, to the co- line of the azimuth from the south, at the time of the equinox. To find the azimuth by the globe, see GEOGRAPHY.

Magnetical Azimuth, an arch of the horizon intercep- ted between the azimuth, or vertical circle, passing through the centre of any heavenly body, and the magnetical meridian. This is found by observing the object with an azimuth-compass.

Azimuth-compass, an instrument adapted to find, in a more accurate manner than by the common sea-com- pass, the sun or stars magnetical amplitude, or azi- muth. See COMPASS.

Azimuth-dial, one whose style or gnomon is at right angles to the plane of the horizon.

Azimuth-circles, called azimuths, or vertical circles, are great circles of the sphere, intersecting each oth- er in the zenith and nadir, and cutting the horizon at right angles in all the points thereof.

AZOGA ships, are those Spanish ships commonly called the quick-silver ships, from their carrying quick-silver to the Spanish W. Indies, in order to extract the sil- ver out of the mines of Mexico and Peru. These ships, strictly speaking, are not to carry any goods unlent for the king of Spain's account.