Four members of the Faculty of Arts and Sciences have received promotions, University authorities announced yesterday. Among those elevated is L. Don Leet '30, Director of the Seismograph Station at Harvard, Massachusetts, who has been made a full professor of Geology.

Herbert Bloch was raised to the rank of associate professor of Greek and Latin, while Louis Hartz '40 and David B. Truman became assistant professors of Government in the other three elevations.

Professor Leet, one of the nation's leading seismologists, was among the scientists who took part in the Los Alamos atom bomb test two years ago. As a specialist in the study of vibrations, Leet has recorded the effects of earthquakes and blasts on his underground machines. He is the author of a forthcoming book on "Causes of Catastrophes."

Born in Berlin-Charlottenburg, Germany, Bloch studied at the Universities of Berlin and Rome. He engaged in archeological field work near Rome before coming to this country in 1939 to join the Department of the Classics.

Hartz Was Summa Cum Laude

Hartz graduated summa cum laude from Harvard in 1930 and received his Ph.D. here last year. Since 1945 he has been a teaching fellow here. His book, "The People's Will: A Study of Politico-Economic Thought in Pennsylvania, 1776-1860," is now in press.

Truman is a native of Evanston, Illinois, and was graduated from Amherst College in 1935. He did graduate work at Chicago, where he received a Ph.D. in 1939. During the war, he did radio research for the Federal Communications Commission, worked for a time in the Bureau of Agricultural Economics and served in the United States Naval Reserve. He was Deputy Chief of the Morale Division, U. S. Strategic Bombing Survey (Pacific).