Sir Joseph John Thomson, a British physicist, discovered the electron in 1897. In experiments studying electric discharge in cathode tubes, he noted a high value for the ratio of charge to mass. His observation led him to identify the first subatomic particle, the electron.Know More
Thomson won the Nobel Prize for Physics in 1906 for his discovery. He also received a knighthood in 1908. His research into the nature of particles led to the invention of the mass spectrograph.
Thomson's father wanted him to become an engineer but could not afford the fees for his training. Instead, Thomson attended Owens College in Manchester, Britain. The school's science faculty recommended Thomson to Trinity College in Cambridge, where he studied to become a mathematical physicist.Learn more about Inventions
J.J. Thompson conducted his cathode ray experiment in 1897. Thompson had a long-lasting interest in the atomic structure, and this experiment resulted in the discovery of the electron.Full Answer >
Physicist Ernst Ruska and German engineer Max Knoll are credited with creating the first electron microscope in 1932. It permitted researchers greater magnification and resolution than traditional light microscopes.Full Answer >
The idea of electron shells was developed by Niels Bohr in his 1913 model of the atom, which places electrons into stable orbits around the nucleus. The Bohr model was a modification of the Rutherford model, which did not require that electrons move in orbits of fixed size and energy.Full Answer >
T.J. Marshall is credited with improving the design of the fire extinguisher, with a patent issued on March 26, 1872. He invented a system in which water is pumped through pipes in buildings to individual sprinkler heads. The system can be activated by manually turning a valve in the building.Full Answer >