Meanwhile, Pryce investigated how long a runaway nuclear chain reaction in an atomic bomb would continue before it blew itself apart. He calculated that since the neutrons produced by fission have an energy of about this corresponded to a speed of . The major part of the chain reaction would be completed in the order of (ten "shakes"). From 1 to 10 per cent of the fissile material would fission in this time; but even an atomic bomb with 1 per cent efficiency would release as much energy as 180,000 times its weight in TNT.