| In 1911, Ernest Rutherford conducted experiments at
Manchester University in which he bombarded gold foil with alpha particles. These
experiments were followed in 1919 when he conducted a series of experiments bombarding
nitrogen gas with alpha particles.
The photograph shows Rutherford (right) and Hans Geiger, who devised an ionisation
counter (now known as a Geiger counter).

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With kind permission of the University of Manchester. |