emission of energy of 3·6 × 10 5 ergs per second. Now when radio-active equilibrium is reached, the number of α particles expelled from radium C per second is equal to the number of α particles expelled per second from radium at its minimum activity. This number, n , is 6·2 × 10 10 (section 93).
substituting the value of n, and the value of the ionic charge e. The value of e in this case has not been assumed, since n = i/e, where i was the measured current due to the charge carried by the α rays.
From the magnetic deflection, it is known that
From these two equations we obtain
These values are in surprisingly good agreement with the previous values of the writer and Des Coudres (section 91). On account of the uncertainty attaching to the value of n, not much weight can be attached to the determination by this method of the constants of the α particles.