Herbert G. MacPherson

Herbert G. MacPherson (1911 to 1993) was an American nuclear engineer and deputy director of Oak Ridge National Laboratory. After a physics doctorate at Berkeley in 1936 he joined the National Carbon Division of Union Carbide, where his knowledge of carbon arc spectra let him see that even high-quality graphite held traces of boron that would absorb neutrons. With colleagues he developed thermal purification techniques that produced AGOT graphite, described by W. P. Eatherly as the first true nuclear grade graphite. By November 1942 National Carbon had shipped 250 tons of it to the University of Chicago for Chicago Pile-1, and it was also used for the X-10 reactor at Oak Ridge and the Hanford reactors. From 1956 he led the Molten Salt Reactor Experiment at Oak Ridge, which was completed in 1965 and ran until 1969. He later taught nuclear engineering at the University of Tennessee and was elected to the National Academy of Engineering in 1978.