The more energetic the particles produced by an accelerator, the more interesting physics they can create in the laboratory. Lawrence did not remain satisfied with the million-volt protons provided by his eleven-inch cyclotron, but hoped to increase the energy by a factor of ten or more. Higher energies required bigger magnets and faster oscillators. It also demanded more money. It was not a good time to raise money for research, as the U.S. reached the depths of the Great Depression. Universities in general suffered less than other segments of society. Still, in 1933 the physics department of the University of California at Berkeley had to cut its research budget by a third and impose an austerity program of lower salaries and fewer teaching assistants.
Lawrence was obliged to seek new funding sources. He was as adept at fundraising as at building new devices, despite the grim Depression environment, he found donors for his next machine. One patron was the Research Corporation, a company that filed patents on behalf of university professors and plowed the proceeds back into academic research. Another was the Chemical Foundation, set up by the federal government to administer the thousands of German patents seized in World War I. The Research Corporation urged Lawrence to take a patent on his cyclotron. Lawrence at first resisted. Like many prewar scientists, he did not think of academic research as a money-making business. But when he learned that an engineer at Raytheon had applied for a patent on a similar circular accelerator, the fear of an industrial monopoly made him file an application for the cyclotron (the patent was granted in 1934).
The university provided the remainder of the funds and a building to house the new machine. In August 1931 an old civil engineering building was made available for Lawrence, which came to be called the Radiation Laboratory. The building housed a new 27-inch cyclotron, with an 80-ton magnet originally built to power a transatlantic radio link in World War I. Lawrence acquired the magnet at a discount as war surplus. By September 1932 the cyclotron was accelerating protons up to 3.6 million electron-volts.
In what became typical for Lawrence, he was already planning his next machine before the current one started working. In 1937 he had a 37-inch cyclotron operating, followed two years later by a 60-inch device. To build the succession of machines Lawrence solicited $550,000 worth of expenses and equipment for his laboratory between 1931 and 1940. Donors included the state of California through the university; private philanthropies, notably the Macy and Rockefeller Foundations; and the federal government through the National Cancer Institute. Industrial firms donated equipment.
—A student of Lawrence in 1938
The federal government also provided support through two New Deal agencies, the Works Progress Administration and the National Youth Authority, which put electricians, machinists, carpenters, and other technical assistants to work in the Rad Lab on the government's payroll. The Depression also produced a steady supply of physicists willing to work for nothing in order to learn cyclotronics. From 1933 to 1940 the Rad Lab had several graduate and postdoctoral students paying their own way at the lab. They helped the Rad Lab staff grow from a total of ten in 1932 to sixty in 1939.
Lawrence found another important way to elicit funds—appeals to biomedical applications. Lawrence's colleague David Sloan had put his linear accelerator to work at the university's medical school as a powerful source of X-rays. The example encouraged Lawrence to promote similar applications of the cyclotron, such as the production of radioactive isotopes, which had medical uses in attacking cancers and as "tracers" in research on metabolism, and beams of neutrons, which promised to rival the utility of X-rays.
Philanthropies at the time donated far more money to medicine, public health, and biology than to physics. In 1933 the Rockefeller Foundation, a dominant supporter of American fundamental research in years between the wars, decided to concentrate on applications of the methods of physics and chemistry to biology and medicine. But Lawrence did not just give lip service to biomedicine. He believed in the promise of particle accelerators as a possible weapon against cancer. In 1937 Lawrence brought his mother, diagnosed with inoperable cancer, to San Francisco for treatment with Sloan's X-ray tube, after which her condition dramatically improved.
—Lawrence to Niels Bohr, 1935