Nuclear magnetic resonance electromagnet, 1951-1953.
© Science Museum / Science & Society Picture Library
This electromagnet was built by Rex Richards (b 1922) and colleagues at Oxford University. Nuclear magnetic resonance (NMR) allows scientists to investigate the atoms inside a specimen, by 'interrogating' the atoms using radio waves of a defined frequency from a transmitter close to the specimen and detecting and decoding the returned transmisions that the atoms give. NMR is a valuable means of providing information on the structure of molecules. It has also become an extremely effective clinical diagnosis tool in medicine, as a non-invasive method of obtaining images of sections through the human body.