John Michael Callow died at his residence, Nutfield Priory, near Redhill, Surrey, on July 26th, 1940, in his 74th year.
On leaving school at Norwich in 1884, he became an articled pupil to Charles J. Watts, consulting mechanical engineer; in the same city, and at the conclusion of his articles he emigrated to the United States, where he resided for nearly fifty years.
From 1890 to 1895 he was engaged as draughtsman and in other capacities in a variety of work for engineering firms and mining companies in Colorado, and then took up the position of manager for the Golden Horn Mining Co., at Silverton, also in Colorado. In 1898 he joined the staff of Samuel Newhouse at Salt Lake City, but two years later he organized the General Engineering Company of Salt Lake City, New York, and London, and as president and general manager built up a connexion involving a wide variety of metallurgical work throughout the United States, Canada, Mexico and England.
Incidentally, he was well known as the inventor of various ore-dressing devices, of which the Callow screen and pneumatic flotation plant are outstanding examples. He was awarded the James Douglas Medal of the American Institute of Mining and Metallurgical Engineers in 1926, during the two years that he was a director of the Institute. He was also a director of the Engineering Foundation, New York City.
Mr. Callow was elected a Member of the Institution in 1928.
Vol. 50, Trans I.M.M. 1940-41, pp. 541-2
