Don died July 16, 2014, in Spring Run, Pa. He was 97.
He majored in physics at Princeton and was elected to Phi Beta Kappa. Don was a member of the Student Tutoring Association and a manager of Terrace Club, and played soccer and squash. Freshman year he roomed at Pyne, sophomore and junior years at Witherspoon, and senior year at Foulke.
He earned a master’s degree from Columbia University and then did a three-year fellowship in Langmuir film research. From 1942 to 1946 he was a research physicist at Columbia’s Division of Government Aided Research and worked for the Manhattan Project. In 1950, he received a Ph.D. in physics from Columbia and became a research physicist for the DuPont Co., where he worked until his retirement in 1986.
Don was an active Quaker and a director of Quaker Funds and the DuPont Experimental Station Credit Union. He was a talented musician, volunteering to play the piano at many functions. He played on the Hockessin (Del.) Friends softball team and enjoyed squash, tennis, and pingpong. He volunteered on local farms.
Don was predeceased by his wife of 52 years, Elizabeth, and son Peter. He is survived by his daughters, Dorothy and Elisabeth; sons Roger C., Alan H., and Avery M. Cook; nine grandchildren; two step-grandchildren; and five great-grandchildren.