The octant has an ebony frame and limb with a brass index arm, fittings, and a stop for the index arm. It also has inlaid ivory plates on the crossbar, which is missing, and on the back of the frame. There are remains of a slow motion device, that is probably a later addition, and the clamping screw is on the back of the index arm. The socket shades are missing. Index-glass adjustment is made by a screw, however on this item both the glass and this screw are missing. Both horizon glasses are also adjustable by levers, wing nuts, and milled clamping screws. The sight vane has two pinholes and a swivelling shutter, whereas the back sight vane has one pinhole. A pencil or screwdriver is missing from the crossbar. The octant has no box.

The instrument has inlaid ivory scale from -5° to 95° by 20 arcminutes, measuring to 91°. The octant has a broken ivory vernier measuring to 1 arcminute, with zero at the centre.