Ionization by Moving Electrified Particles

T HE theory developed in this paper is based on the following assumptions :-1. Cathode or positive rays when they pass through an atom repel or attract the corpuscles in it and thereby give to them kinetic energy. 2. When the energy imparted to a corpnsole is greater than a certain definite value-the value required to ionize the atom-a corpuscle escapes from the atom, and a free corpuscle and positively charged at~om are produced. We must first find under what circumstances a cathode ray moving with a given velocity will lose when it passes by a corpuscle a quantity of energy greater than the amount required to ionize an atom. In my ' Conduction of Electricity through Gases' it is shown that when a body with a charge E1 in electrostatic units and mass Mt is projected with a velocity V towards a body with a charge E2 and mass Ms at rest, the energy Q transferred to the latter is given by the equatioa 4M1M2-. Q-(Ml+M~)~'rsm t~,