Rutherford
A promising young scientist in September 1895, 24-year-old Ernest Rutherford said good-bye to his fiancee, Mary Newton. Rutherford was leaving the island of New Zealand, where he had grown up. His destination was Cambridge University in England, halfway around the world. He looked forward to working at the Cavendish Laboratory. Rutherford brought with him his electromagnetic wave detector. He had found a way to detect radio signals using magnetized steel needles. In Cambridge, he managed to send a message to a room three-quarters of a mile away. Impressed with Rutherford’s talent, J.J. Thomson invited the young scientist to collaborate with him. Under Thomson’s guidance, Rutherford measured the electric current in gases ionized by X-rays and ultraviolet light. When the atoms in a gas acquire a positive or negative electric charge, the gas is said to be ionized. Rutherford wondered if Becquerel’s uranium rays would ionize gas. Rutherford set two parallel metal plates one above the other. He spread uranium powder on the bottom plate. After connecting the plates to a battery, he measured the electric current between them. The current told him that uranium rays were ionizing the gas.
