In the 1930s, Professor Francis Bitter designed a new kind of high-powered magnet, which is still the basic design for the world’s strongest magnets. Making a strong magnetic field requires a large amount of energy, which generates heat. However, the heat then interferes with the magnetic field. Bitter’s design used layers of conductive plates with holes for water-cooling, dissipating the excess heat and increasing the magnetic field strength. The power requirements were enormous, so this first magnet was built inside of Boston Edison’s Scotia Street substation. Bitter details this pioneering effort in his draft report to the American Philosophical Society. His work not only opened up new fields in physics and electrical engineering, but had immediate practical effects as well. During World War II, Bitter worked with English scientists to defeat magnetically triggered German undersea mines by demagnetizing steel battleships. He was a passionate teacher and an enthusiastic participant in educational outreach efforts. In addition to a popular book, he worked with Richard Leacock to make this film for the famous PSSC physics curriculum project.

On loan from Institute Archives and Special Collections. Playing on the monitor, A Magnet Laboratory by Richard Leacock, 1959, courtesy of the Academic Film Archive of North America.