He prepared at Mercersburg Academy. At Princeton he majored in biology, achieving second group departmental honors. He was on the varsity tennis squad, and was a church monitor and member of Campus Club.
Upon graduation, Jack joined E.I. du Pont de Nemours & Co. as a chemist for five years, then worked at Rohm and Haas Co. until his early retirement in 1978. He particularly enjoyed his position as corporate manager for urban affairs.
After retirement, his “second career” com bined the major interests he shared with his wife, Frances: tennis and international goodwill. The pair organized and led enthusiasts to Egypt, Kenya, Russia, and Spain, promoting goodwill through tennis tournaments.
Jack was a nationally ranked Super Senior tennis player, inducted into the U.S. Tennis Association Middle States Chapter Hall of Fame in 2001. The Geisels often said their most rewarding endeavor was their volunteer work with the National Junior Tennis League, coaching inner-city teams and helping to break down racial barriers.
He is survived by Frances, his wife of 66 years; sons John Jr. and Ritchie ’67 and their wives; four grandchildren; and 10 great-grandchildren. His classmates offer them their deepest sympathies.