An oxidised brass theodolite signed W.&L Gurley, Troy N.Y., with graduated bubble level, rack-and-pinion focusing, the half-vertical circle with silvered scale and vernier, tangent screw and clamp, on twin A frames, with bubble level and cross bubble, the horizontal circle with compass box, blued steel needle, horizontal circle with twin vernier scales on four screw tripod base, in fitted mahogany case - 11¼in.high