A glazed azimuth circle with a silver scale around the circumference. Scale graduated 0-360 degs. On top of the glass is a framework of four radial arms, two of which terminate in verniers, graduated 0-30. This framework turns in azimuth and carries fore and back sight. Fore sight consists of open arch and thread with a small celestial reflector and prism. Back sight is a truncated fan-shaped plate with slit at centre. This also has two filters. Both sights are hinged.