Nocturnal, made of boxwood, with a shaped handle pierced by a heart and the inscription 'BOTH BEARS' at the top of the handle. On the front of the main disc is a date scale, which is subdivided to 10 days and 2 days, and an hour scale numbered anticlockwise 1-12, 1-12. The rotatable disc also has an hour scale, as well as a lunar age scale and two shaped pointers marked 'GB' and 'LB'. A rotating pointer is fixed to the centre of the rotatable disc. The instrument's central sighting hole is protected by a brass fitting. The Rule of the North Star is inscribed on the back of the main disc, which also has a compass rose with sixteen points and lines for the by-points.