Patterson type G4 electric hand lamps. The lamps are in two main parts. The bottom part consists of a welded steel cylinder which holds the alkaline battery. This cylinder is 185mm in height and a portion of it is square. The top has a screw thread so that the top of the lamp screws on. , , , , The top of the lamp consists of a steel pressing, to which the bulb assembly is fitted. The bulb is covered by a thick glass dome which is ribbed internally. The glass is protected by foue iron pillars, the top of which are connected to a steel plate. A carrying hook is attached to this plate by a ring. A magnetic lock fitted to the top part of the lamp prevents the two parts being unscrewed without the use of a special magnet. , , , , The lamp was turned on and off by rotating the top of the lamp slightly, relative to the bottom. Each lamp has a brass plate fixed to the top with the inscription: "Type G.4. Patterson Lamps Ltd. Gateshead-on-Tyne. Appd. under Ltg. Sched." Height: 310mm x Length: 110mm x Width: 110mm. No. "1854" stamped on top and base. Weight: 1.82KGS. Condition in 1999: good condition, needs cleaning, accumulator is removed. Date of manufacture 1950. Place of manufacture: Gateshead on Tyne.