The word electron had been suggested in 1891 by G. Johnstone Stoney to indicate the natural unit of electrical charge, that is, the amount of electricity that must pass through an electrolytic cell to release one hydrogen ion to the cathode.
The value found by Thomson for the ratio between charge and mass of the electron differs by about 3% from the one obtained in 1932-33 by deflection with radiofrequency fields or spectroscopy (Zeeman effect). The good quality of the results obtained by Thomson is certainly owing to the null method he used in measurements.