Bidspirit auction | British GPO Mahogany-Cased Single-Needle Telegraph

British GPO Mahogany-Cased Single-Needle Telegraph Indicator - An antique telegraph galvanometer of the single-needle type, manufactured for the British General Post Office (GPO). The instrument is housed in a mahogany case featuring a pointed Gothic arch profile. The case is constructed in two sections; the front panel, which incorporates a glazed brass circular bezel, is detachable from the main body and secured by a top-mounted brass latch. The entire assembly sits on a rectangular mahogany plinth. The silvered metal dial is engraved with the initials G. P. O. and the serial number 9943. It features a central vertical black needle positioned between two white stop-pins, with a horizontal brass retaining bar across the centre. The internal mechanism, visible when the case is opened, comprises an electromagnetic coil, a vertical steel bar, a tension spring, and a knurled brass adjustment knob. The rear of the case is fitted with two large slotted brass terminal nuts for electrical connections. A small number 50 is stamped into the wood on the reverse. Height: 21.5 cm Width: 15 cm.