In J.J. Thompson’s cathode ray tube experiment electricity was discharged in a cathode ray tube with electricity flowing from the cathode to the anode. The particles that ejected from the cathode were deflected by a positive charged plate, which led Thompson to propose that the cathode rays are negatively charged particles. In the plum pudding analogy Thompson believed that the electron is made up of sea of electrons that are embedded in a pudding of positively charged particles.