Found with an Excel precision lathe, this self-contained bench-mounted countershaft provides both a variable-speed drive by a swashplate mechanism and, by using a air of jockey pulleys, a means of keeping the belt tight. Speeds were varied by using a long lever protruding from the top of the  unit
Cast into the casing is an elongated letter "H" and "GEARS" between the upper legs, "BRIT PAT" between lower legs together and the number 1491958 across the bar. Its only drawback in the installation illustrated is the need to slide the unit from side to side in order to line up the belt with the that chosen on the lathe's headstock. If set to run an intermediate countershaft, fitted with pulleys matching those on the headstock, this slight deficiency would be overcome.