John Van Nostrand Dorr died in Wallingford, Connecticut, on 29th June, 1962, at the age of 90.
Mr. Dorr was born and educated in Newark, New Jersey. After working in Thomas Edison’s laboratories for two years Mr. Dorr entered Rutgers College, graduating B.Sc. (Chemistry) in 1894. From then until 1901 he undertook analytical work with various mining and milling companies in Colorado and South Dakota.
Mr. Dorr first set up in business as managing partner in Lundberg and Dorr at Deadwood, South Dakota, in 1901 and, with his colleagues, for several years worked on cyanide mills and a number of inventions, among them the Dorr classifier, thickener and air lift agitator. The rapid expansion of his activities led, in 1910, to the foundation of the Dorr Cyanide Machinery Co., Inc., followed, in 1916, by the incorporation of the Dorr Co., Inc., New York, and later the formation of a number of holding companies. His European companies included the Dorr Co., Ltd., London, and Dorr Gesellschaft, Berlin, both founded in 1925. Subsidiaries were later formed throughout the world. In 1954 came the merger with Oliver United Filters, Mr. Dorr being founder-chairman of Dorr-Oliver, Inc. He continued to serve on the board of directors until 1961.
His numerous inventions and achievements were widely acclaimed. He was awarded honorary degrees by Rutgers University, South Dakota School of Mines, Michigan College of Mining and Technology, Columbia University, Colorado School of Mines and the Polytechnic Institute of Brooklyn.
Mr. Dorr was a member of technical and professional bodies in many countries. His outstanding work was recognized and among the many awards he received were the John Scott Medal of the Franklin Institute, the James Douglas Medal of the American Institute of Mining, Metallurgical and Petroleum Engineers, the Perkin Medal of the Society of Chemical Industry and the Founders Award of the American Institute of Chemical Engineers, of which body he was President in 1932 and 1933. Mr. Dorr was also an Honorary Member of the South African Institute of Mining and Metallurgy. He had a long record of service on many committees and boards, both institutional and national; he served on the National Research Council Advisory Committee for Metals and Minerals, National Committee for Reorganization of the Executive Branch of Government, and Committee on Patents of the U.S. House of Representatives National Advisory Council.
Among his many technical publications was the joint paper (with F.L. Bosqui) entitled ‘Recent developments in classification and fluidization as applications of the principle of particle dynamics’ published in the Institution’s ‘Recent developments in mineral dressing in 1953. He was also the joint author of Cyanidation and concentration of gold and silver ores’ (McGraw-Hill, 1936).
Mr. Dorr was elected to Associate Membership of the Institution in 1905 and was transferred to Membership in 1911.
Vol. 19, Trans IMM 1963-64, pp.763-4
