The octant has an ebony frame and limb with a brass index arm, fittings, and a brass stop for the index arm. It also has inlaid ivory plates on the crossbar and on the back of the frame. There is no tangent screw and the clamping screw is located on the back of the index arm. The octant has three socket shades in orange, green, and red. Index-glass adjustment is made by a screw, however the glass is now missing. Both horizon glasses are adjusted by levers, wing nuts and milled clamping screws. The sight vane has two pinholes and a swivelling shutter, whereas the back sight vane, which is broken, has one pinhole. A pencil or screwdriver is missing from the crossbar. Simple decorative marks are found on the ivory plate on the crossbar. The octant has no box.

The instrument has an inlaid ivory scale from -5° to 95° by 20 arcminutes, which is vice versa for the zenith distance, measuring to 86.5°. The octant has an ivory vernier measuring to 1 arcminute, with zero at the centre.