A rare wood cased 7” Duplex Test Gauge No 43720 by Davies, Shephard (Syd) Pty Ltd c1930

Duplex test gauge having 7“ white painted and black printed open centred dial with duplicated scale calibrated in Lbs/inch with a range from 0-650, the upper part marked “Duplex-Test-Gauge” with maker’s details below. “Davies, Shephard (Syd) Pty Ltd. Twin japanned pointers, open centre affording a view of the jewelled movement comprising twin Bourdon tubes, and associated levers and gearing, assembled between two plates. All contained in a two part drum form case, inlet threaded ½” BSP, flat to head struck “9/44” with broad arrow property mark. Attached illegible label.

Presented in its original red baize lined mahogany case, lock and key.

Condition: The dial very good with no visible losses, some discolouration, the reflector ring with some ageing and minor losses. The movement remains untested though a visual inspection would suggest good function. The timber case worn, with abrasions and discolouration, carry handles and swinging clips missing.

Comments: Extensive research has shown brought notice of only one other similar gauge of this type, and this particular gauge is not a duplex or compound type as we may understand by modern standards. As a test gauge it was designed as a fail safe, two autonomous gauges working in unison, the idea being that if one failed or fell dramatically out of calibration this would become immediately obvious by the disparity in readings. This system also offered the operator the ability to take an average reading which should be closer to the true pressure being measured.

Davies, Shephard (Syd) Pty Ltd were known for the production of high quality parts for torpedos, particularly during the Second World War. This gauge carries an added military part code and date of 9 /44, suggesting that it was requisitioned for use in 1944.

Very ususual, and certainly a collector’s piece.