Canal rays also known as anode rays are positively charged radiations which led to the discovery of positively charged subatomic particle called ‘Proton’. These rays were produced when high voltage electricity was passed through a gas at very low pressure taken in the discharge tube. This experiment led to the discovery of proton. Proton has a charge, equal in magnitude but opposite in sign to that of the electron. Its mass was approximately 2000 times as that of the electron.