The octant has an ebony frame and limb with a brass index arm and fittings. It has inlaid ivory plates on the crossbar and on the back of the frame. The tangent screw is positioned on the top of the index arm and the clamping screw is on the back. The octant has three socket shades, two red, and one green. Index-glass adjustment is made by a screw. On the horizon glass it is made by a lever and worm gear and on the back horizon glass by a lever, wing nut and a milled clamping screw. The sight vane has two pinholes and a swivelling shutter, which is missing, whereas the back sight vane has one pinhole. An ivory-capped pencil is fitted in the crossbar. The octant is contained in an oak keystone box, with a handwritten label in the lid ‘Given to me by Mr. Charles Wilson 1914’.

The instrument has an inlaid ivory scale from -2° to 101° by 20 arcminutes, measuring to 95°. The octant has an ivory vernier measuring to 1 arcminute, with zero at the right.

Davis, an optician, may have been the retailer rather than the maker of this instrument.