After serving in the Union Army during the Civil War, General Theodore Grenville Ellis resumed work as an engineer in Hartford, Conn. In 1867 he was placed in charge of the U.S. Corps of Engineers navigation improvement study of the Connecticut River. For that task, in 1874, he built a current meter with four revolving cups and a four-blade rudder that was similar to, but smaller than, the current meter designed by Daniel F. Henry. The Department of Civil Engineering of the University of Wisconsin donated this Ellis meter to the Smithsonian.
Ref: Buff & Berger, Hand-Book and Illustrated Catalogue of the Engineers’ and Surveyors Instruments (Boston, 1890), pp. 61-62 and 135-137.
Arthur H. Frazier, Water Current Meters in the Smithsonian Collections of the National Museum of History and Technology (Washington, D.C., 1974), pp. 62-63 and 74-75.
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