Argus Arc Lamp for Microscopical Use, by W. Watson & Sons, London, c. 1926

The lamp is held on a retort stand with a circular base. It is attached by a brass coloured collar with a tightening screw that allows the height to be adjusted. The power connections are on this side of the body with two insulated wires going to brass holders for the carbon rods. On the other side of the body is a large double mill-edged control that moves both of the rod-holders. This side is also inscribed with the manufacture's name. A bar passes from the collar on the stand though the body to a wing-nut and the lamp can pivot on this bar. A blackened metal tube with the lens is mounted on the top of the body held by two screws. The tube can pivot backward revealing the point at which the carbon rods arc.