Separating isotopes with a mass spectrometer was a technique Oliphant had pioneered with lithium in 1934. Lawrence began converting his old 37-inch cyclotron into a giant mass spectrometer. On his recommendation, the director of the Manhattan Project, Brigadier General Leslie R. Groves, Jr., appointed Oppenheimer as head of its Los Alamos Laboratory in New Mexico. While the Radiation laboratory developed the electromagnetic uranium enrichment process, the Los Alamos Laboratory designed and constructed the atomic bombs. Like the Radiation Laboratory, it was run by the University of California. Electromagnetic isotope separation used devices known as calutrons, a hybrid of two laboratory instruments, the mass spectrometer and cyclotron. The name was derived from "California university cyclotrons". In November 1943, Lawrence's team at Berkeley was bolstered by 29 British scientists, including Oliphant. In the electromagnetic process, a magnetic field deflected charged particles according to mass. The process was neither scientifically elegant nor industrially efficient. Compared with a gaseous diffusion plant or a nuclear reactor, an electromagnetic separation plant would consume more scarce materials, require more manpower to operate, and cost more to build. Nonetheless, the process was approved because it was based on proven technology and therefore represented less risk. Moreover, it could be built in stages, and would rapidly reach industrial capacity. Oak Ridge Responsibility for the design and construction of the electromagnetic separation plant at Oak Ridge, Tennessee, which came to be called Y-12, was assigned to Stone & Webster. The calutrons, using 14,700 tons of silver, were manufactured by Allis-Chalmers in Milwaukee and shipped to Oak Ridge. The design called for five first-stage processing units, known as Alpha racetracks, and two units for final processing, known as Beta racetracks. In September 1943 Groves authorized construction of four more racetracks, known as Alpha II. When the plant was started up for testing on schedule in October 1943, the 14-ton vacuum tanks crept out of alignment because of the power of the magnets and had to be fastened more securely. A more serious problem arose when the magnetic coils started shorting out. In December Groves ordered a magnet to be broken open, and handfuls of rust were found inside. Groves then ordered the racetracks to be torn down and the magnets sent back to the factory to be cleaned. A pickling plant was established on-site to clean the pipes and fittings. Tennessee Eastman was hired to manage Y-12. Y-12 initially enriched the