<Tr> <Th_colspan="2"> Signature </Th> </Tr> <Table> External video <Tr> <Td_colspan="2"> </Td> </Tr> <Tr> <Td_colspan="2"> The Early Life of J.J. Thomson: Computational Chemistry and Gas Discharge Experiments, Profiles in Chemistry, Chemical Heritage Foundation </Td> </Tr> </Table> <Tr> <Td_colspan="2"> The Early Life of J.J. Thomson: Computational Chemistry and Gas Discharge Experiments, Profiles in Chemistry, Chemical Heritage Foundation </Td> </Tr> <P> Sir Joseph John Thomson OM PRS (/ ˈtɒmsən /; 18 December 1856--30 August 1940) was an English physicist and Nobel laureate in physics, credited with the discovery and identification of the electron; and with the discovery of the first subatomic particle . </P>

Who is credited with a supplemental discovery and what was it