XI. Experimental researches on the electric discharge with the chloride of silver battery

The question has been mooted whether there is a polarisation of the terminals of a vacuum-tube after the discharge through it has been interrupted by breaking connexion between it and the source of electricity. This question we understand in the sense—does there exist a chemical polarisation as is the case for instance with the terminals of a voltameter under similar circumstances ? It is evident that if a polarisation of this kind could he proved, the formula used for determining the tube potential (“ Phil. Trans.,” Part I, vol. clxxi, p. 65) would no longer hold good. The problem is by no means easy of solution, and it has engaged our attention for the last five months. We believe, however, that the few experiments we are about to describe, and which we select from a long series, will show that there is really no such polarisation of the terminals.