John William Rayleigh, British physicist, c 1910-1920.
© Science Museum / Science & Society Picture Library
Photogravure by Walker & Cockerell after a photograph by Maull & Fox. John William Strutt Rayleigh, third Baron Rayleigh (1842-1919) was a nobleman who divided his time between his estates and his scientific studies. His experiments in electricity led to the establishment of the standards of resistance, current, and electromotive force. In 1904 he was awarded the Nobel Prize for Physics for his investigations of the densities of gases, and for his discovery of argon.