as a new lighting system that enabled him to take pictures in one thirty-thousandth of a second. During this expedition, Henry Allen Moe, then president of the Guggenheim Foundation, Professor Raymond Birge, head of the physics department at the University of California, Berkeley, and German physicist Hans Bethe visited the mountaintop laboratory. In 1941, Powell went to the University of California, Berkeley to continue cosmic ray research with Robert Brode. Scientific contribution during the Manhattan Project Upon finishing the Guggenheim Fellowship in 1942, Powell began work in the Manhattan Project. He became head of the magnet group, which designed the magnets for the calutrons. Developed by Ernest O. Lawrence, these large machines were used to separate uranium isotopes. Powell worked on the pilot models first at the Radiation Laboratory at University of California, Berkeley and then on the racetracks at Oak Ridge, Tennessee. Postwar work at the radiation laboratory Powell was made an associate professor of physics at the University of California, Berkeley in 1946, and continued to lead the magnet group at the Radiation Laboratory after the war. He contributed to the development of the 184-inch synchrocyclotron and the 300 MeV electron synchrotron. He also constructed the 30-inch propane chamber. He introduced the use of scotchlite to illuminate the bubble chamber and was actively involved in the design of Argonne Laboratory's 12-foot heavy liquid chamber. In 1951, he was made a professor of physics at Berkeley. While directing the research of 33 Ph.D. students, Powell and his colleagues at the Lawrence Berkeley Laboratory published approximately 40 papers. Because Powell held a particular interest in optics, he taught the upper level optics courses. Musical interests Powell played several instruments, including the violin and the bagpipe. Collaborating with W.F. Fry, a physicist at the University of Wisconsin, Powell conducted research on the construction on violins, measuring such famous instruments as the Stradivarius and Guarnerius violins. The prototypes of the violins created were given to students. One was given to his granddaughter Heidi Powell Priddy. Personal life Powell married Fredrika Richardson in 1930 in Cambridge, Massachusetts. They had three children, Wilson M., David Richardson and Fredrika. They divorced in 1955. Powell married Dorothy J. Gardner in 1956, and adopted her daughter Claire. His grandchildren from Wilson M. include Mayan Archaeologist Christopher Powell, Cyber Security Consultant Gordon Powell, artist/filmmaker Heidi Powell Priddy, and Architect Benjamin Powell. Grandchildren from David Richardson include writer-producer J