The cyclotron, invented by Ernest Lawrence in the 1930s, is a unique circular particle accelerator, which Lawrence himself referred to as a "proton merry-go-round." In reality, the cyclotron specialized in smashing atoms. Part of this atom-smashing process requires very large, very heavy magnets -- sometimes weighing up to 220 tons. In this photo, workers at the Federal Telegraph facility in Menlo Park, California, are smoothing two castings for 80-ton magnets for use in one of Lawrence's cyclotrons at the University of California, Berkeley. Lawrence passed away in 1958 -- and just 23 days later, the Regents of the University of California voted to rename two of the university's nuclear research sites: Lawrence Livermore and Lawrence Berkeley Laboratories. | Photo courtesy of Lawrence Berkeley National Laboratory.

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