Eighty-five years ago today, on August 30, 1940 (July 27, 1940 lunar calendar), physicist Thomson died in Cambridge, England. Thomson was busy doing experiments. On December 8, 1856, Thomson was born near Manchester, England. At the age of 14, he entered Owens College, studied engineering and then science, and was awarded a scholarship to Trinity College, Cambridge University. After graduating in 1876, he was a member of the college, holding various positions and living his life. He worked in the Cavendish Laboratory under John Raleigh, and succeeded Raleigh as Professor of Physics in the Cavendish Laboratory in 1884. Thomson's most brilliant scientific work was his study of cathode rays, in which he discovered electrons. Using a discharge tube with a high vacuum, and adjusting the deflection caused by the electric and magnetic fields, he calculated the velocity of the rays to determine the ratio of charge e to mass m of the cathode rays. Thomson found that the charge-to-mass ratio e/m of the cathode rays was independent of the type of gas in the discharge tube and the metal of the cathode; about a thousand times smaller than the corresponding value of hydrogen ions in the electrolyte already obtained. He later went on to measure the charge carried by various negative ions and found that the charge in the gas discharge was the same as that in the electrolysis. Thus he finally concluded that cathode rays were negatively charged particles, elementary particles of matter, much smaller than the smallest known atoms. This opened the way for new concepts of atoms and for the study of subatomic particles. In April 1897, Thomson announced his discovery of this entity smaller than the hydrogen atom. Thomson's later research included the study of polar tunneling rays by Eugen Goldstein, which Thomson called anode rays. This research proposed a new method by which cathode rays could be deflected in magnetic and electric fields to separate various atoms and molecules. In this way, Thomson was the first to identify the isotope neon 22. This method was adopted by Francis-W-Aston, who later developed the mass spectrometer. Thomson was awarded the Nobel Prize in Physics in 1906.