G. E. Halm

R. S. Leonard

R. S. Leonard worked for the Tennessee Eastman Corporation at the Y-12 Plant.

Roy V. Henderson

Roy V. Henderson was a janitor at the University of Chicago’s Metallurgical Laboratory (“Met Lab”) during the Manhattan Project.

Clarence Johnson

Clarence Johnson (1912-2012) was a Canadian-born chemical engineer. He was born in Alberta, Canada on November 24, 1912 to Swedish migrant parents.

James J. Johnsey