Azimuth-compass

One very accurately constructed, fitted with reflectors, mirrors, etc. and a card divided into degrees instead of rhumb-points, as on the ordinary compa ; it is employed to take bearings of the sun or other celestial objects to And the magnetic Azimuth, which on comparison with the true Azimuth (calculated from an observation made at the same time of the same body) the variation of the Compa needle is found. Marine Encyclopedia — B b