The octant is made from a mahogany frame, limb and index arm. It has brass fittings, a brass stop for the index arm and an inlaid ivory plate on the crossbar. The bottom of the index arm is of brass and is possibly a repair. There is no tangent screw and the clamping screw is on the back of the index arm. The octant has two red socket shades. Index-glass adjustment is made by a screw, which is now missing, and both horizon glasses by levers, wing nuts and milled clamping screws, one of which is also missing. The sight vane bracket is broken and the back sight vane and the back horizon glass are missing. Two wooden feet are missing from the frame. The octant has no box.

It has an inlaid boxwood transversal scale from 0° to 90° by 20 arcminutes, which is vice versa for the zenith distance, measuring to 90°. The scale reads to 2 arcminutes by the fiducial edge (with an ivory lining) at the end of the index arm.