Dwight was born on November 23, 1921, on a farm near Paullina, Iowa to Claude and Hazle Wilde Johnston. He was raised on the family farm and attended country school at Dale Township No. 5. He was a graduate of Paullina High School and he received a degree in Chemical Engineering in 1942 from the University of Iowa in Iowa City. Following his education he joined the research and development organization of Shell Oil Company. At retirement in 1984, he held the position of senior staff research engineer. His work locations included Los Angeles, San Francisco and Emeryville, California as well as brief assignments in the Netherlands, England and Mexico. From 1942 to 1963, he was engaged in the economic evaluation and design of oil refining and manufacturing processes. He designed ethyl chloride plants near Chester, England and Coatzacoalcos, Mexico, and a hydrogen peroxide plant near Norco, Louisiana. From 1963 to 1984, he led a group engaged in the development of computer tools for the design and optimization of manufacturing processes. He holds a patent for the manufacture of pivalic acid. From 1978 to 1982, he was on an advisory board at the Massachusetts Institute of Technology at Boston for a major United States Department of Energy Project. Dwight was reared in the United Presbyterian Church of Paullina. He was united in marriage to Elsie M. Ward on July 11, 1945 at the Klemme United Methodist Church. He was an active church member throughout his life and is now a member of the Grinnell United Methodist Church. Upon retirement in Grinnell, Dwight was active in Main Street Grinnell, Grinnell 2000, Grinnell Renaissance, Kiwanis, Second Mile and the Mayflower Homes. His hobbies included travel, photography, and a variety of computer applications. He is survived by his wife, Elsie of Grinnell; two sons, Bruce of Albany, California and Clarke of Vallejo, California; one brother, William of Chula Vista, California; two sisters, Joan of McKenna, Washington and Carolyn of Escondido, California.