Born in Nashville, Tennessee, David Nelson Crosthwait Jr. (ME’1913) was considered an authority on heat transfer, ventilation, and air conditioning. He was a research engineer, director of research laboratories for CA Dunham Company in Marshalltown, Iowa, from 1925 to 1930. He was the technical advisor of Dunham-Bush Inc. from 1930 to 1971. He served as the past president of Michigan City Redevelopment.

Crosthwait designed the heating system for Radio City Music Hall at Rockefeller Center in New York City. He was the author of an instruction manual on heating and cooling with water and guides, standards, and codes that dealt with heating, ventilation, refrigeration, and air conditioning systems. Crosthwait received patents on 39 inventions relating to the design, installing, testing, and service of heating, ventilation, air conditioning (HVAC) power plants.

After retiring from business in 1969, he taught a course on steam heating theory and control systems at Purdue. For his achievements, Mr. Crosthwait was named a fellow of the American Society of Heating, Refrigeration, and Air Conditioning Engineers in 1971, making him the first African American to receive this honor. He was awarded an honorary doctorate degree from Purdue in 1975. Crosthwait died in West Lafayette, Indiana, in 1976.