Maker's Name: 
maker unknown
15 × 15 × 19 cm

This is a small dip circle suitable for an undergraduate teaching laboratory.

A dip circle is a magnetic compass with the needle moving in a vertical plane to indicate the inclination of the Earth's magnetic field to the horizontal - the so-called angle of dip.

The angle of dip in Brisbane is about 45 degrees.

The device has a brass baseplate with a bubble level and adjusting screws. The 'compass' part can be rotated until it is aligned with the horizontal component of the Earth's field. The is a mirror behind the needle to help avoid parallex error in reading.  Oddly, the scale shows the angle to the vertical rather than the horizontal.