1. Prof. of Hydraulics, Dept. of Civ. Engrg., Massachusetts Inst. of Tech., Cambridge, Mass.
2. Asst. Prof. of Hydraulics, Dept. of Civ. Engrg., Massachusetts Inst. of Tech., Cambridge, Mass.; formerly, Geologist, Soil and Water Conservation Research Div., Agric. Research Service, U.S. Dept. of Agric