Letter from Thomas Gold to Dr Charles W McCutchen, Department of Health, Education and Welfare, National Institutes of Health, Building 10, Room 3N-114, Bethesda, Maryland Thanks him for the most interesting reprint. If he was still working in that area he would certainly respond in print, since the results are so closely in accord with his work of 1948. He is sending him a couple of reprints for that era. 9 July 1971