Clarence Floyd Hirshfeld (January 30, 1881 – April 19, 1939) was an American electrical, mechanical and consulting engineer, educator, chief of research for the Detroit Edison Co., now DTE Electric Company, author, and inventor, who was awarded the John Fritz Medal posthumously in 1940.
In World War I he took a leave of absence to serve at the United States Ordnance Department in the rank of Major and Lieutenant Colonel.
[1] Afterwards Hirshfeld continued to run his Detroit Edison Company's research department.
"[3] From 1932 to 1939, in the last seven years of his life, he directed development of PCC streetcar as chief engineer.
In his days these form of transportation was introduced in cities, such as Toronto, Brooklyn, Pittsburgh, Washington, Baltimore, Chicago, San Diego and Los Angeles.