Mechanical movements, powers and devices; a treatise describing mechanical movements and devices used in construcive and operative mechinery and the mechanical arts, being practically a mechanical dictionary (1917)
Hiscox, Gardner Dexter, 1822?-1908 · New York : The Norman W. Henley publishing co. · leaf 145
498. IMPACT WATER WHEEL, Leffel pat-tern. Step buckets. Efficiency, eighty-five per cent.
Mechanical movements
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