The octant has a mahogany frame and limb with a brass index arm, fittings, and a stop for the index arm. It also has an inlaid ivory plate on the back of the frame. There is no tangent screw, and the clamping screw is on the back of the index arm. The octant has three socket shades, two red, and one green, which are fastened by a milled screw on the back of the frame. The index glass is fixed and 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 has one pinhole. A pencil or screwdriver is missing from the crossbar. Decorative engravings are found on the lower part of the index arm. The octant is contained in a stepped oak 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 91°.The octant has an ivory vernier measuring to 1 arcminute, with zero at the centre.