" Bacher asked for a receipt from the Army for the material it would soon explode. Los Alamos was officially an extension of the University of California working for the Army under contract and Bacher wanted to document the university’s release from responsibility for some millions of dollars’ worth of plutonium that would soon be vaporized. Bainbridge thought the ceremony a waste of time but Farrell saw its point and agreed. To relieve the tension Farrell insisted on hefting the hemispheres first to confirm that he was getting good weight. Like polonium but much less intensely, plutonium is an alpha emitter; “when you hold a lump of it in your hand,” says Leona Marshall, “it feels warm, like a live rabbit.”2390 That gave Farrell pause; he set the hemispheres down and signed the receipt. "

― Richard Rhodes , The Making of the Atomic Bomb