Electron

   Sir Joseph John Thomson (1856 - 1940) the British Mathematical Physicist, was one of the outstanding pioneers of nuclear physics. His early work involved the pioneers of nuclear physics. His early work involved the application of dynamics to physics and chemistry.

   In 1897, Thomson discovered that cathode rays consisted of negatively charged particles (electrons). Thomson measured their speed and charge and came to the conslusion that these electrons must be nearly to two thousand times smaller in mass than the lightest knowsn atomic particle, the hydrogen ion.

    It was thomson's work that led to to a much greater understanding of electric current for current is made up of a flow of electrons; when electrons in a metal wire move at random there is no current; when a current flows the electrons all move in the same direction.