A device which enabled atoms to be split in apparatus that could be mounted on a laboratory bench.

Built by Ernest Lawrence, it accelerated particles by using high-frequency pulsed magnets to whirl them round in a spiral, gradually imparting energy. This apparatus, together with John Cockcroft and Ernest Walton's accelerator, developed at Cambridge, launched modern particle physics. This allowed scientists to investigate particles less than a billionth of a centimetre across, and helped usher in the age of 'big science', which increasingly became a feature of atomic physics after the Second World War. The race to split the atom was won by Cockcroft and Walton in June 1932, although Lawrence reproduced the result three months later.

Inv. 1938-219