William Alexander (1876-1947)
1917 Patent on liquid speedometer
1949 Obituary 
"WILLIAM ALEXANDER, Wh.Ex., who was born in Edinburgh in 1876, was well known as an authority on problems relating to the separation of steam, air, and gas. He was educated at the Royal Technical College, Glasgow, and the Imperial College of Science, London, winning a National Scholarship mechanics and a Royal Exhibition. After serving his apprenticeship with Messrs. Duncan Stewart and Company, Ltd., and the London and Glasgow Engineering and Iron Shipbuilding Company, Ltd., from 1892 to 1898, he was appointed assistant manager in the high-speed engine department of Messrs. Alley and MacLellan, Ltd., and later was with Messrs. James Howden and Company, Ltd., for whom he designed their first two high-speed engines.
From 1901 to 1905 he was "Young" assistant in engineering at Glasgow University under Professor A. Barr, D.Sc., and during the next three years head of the mechanical engineering department of Wellington Technical College, New Zealand.
In 1912 he became chief lecturer in mechanical engineering at the South African School of Mines and Technology (now Witwatersrand University). On his return to England in 1917 he was attached to the technical department 'of the Air Board, where he was chiefly concerned with the development of aero-engines and research in lubrication. In the following year he went into business on his own account as a consulting engineer in Glasgow, and was actively engaged up to the time of his death, which occurred on 30th December 1947, in developing his inventions, which covered a wide range including the "Teledep" pneumatic depth, draught, and displacement indicator, the "Vortex" appliances—comprising dust collectors and separators for air, gas, and steam—and more recently the "Suprex" oily-water separator. Mr. Alexander's dust collectors have been of great service in the prevention of the pollution of the atmosphere in industrial areas and have been installed in all types of ships including those of the Royal Navy. He was elected an Associate Member of the Institution in 1903 and was transferred to Membership in 1944. In addition he was a Member of the Institution of Naval Architects and an Associate Member of the Institution of Civil Engineers. He was the author of a paper, presented to the Institution in 1917, on "An Energy Diagram for Gas Mixture and Some of its Uses". He also contributed many papers and articles on engineering subjects to various technical societies and was responsible for numerous scientific publications."