The occlusion of the residual gas and the fluorescence of the glass walls of crookes tubes

In a previous paper on the first part of this subject, the writer has described experiments indicating that the occlusion of the gas is due, at any rate in some instances, to the gas being mechanically driven into the glass, in which it forms bubbles on the glass being heated strongly. Since this paper was published, several comments on the writer’s conclusions have appeared, and these have led to the writer making further experimental investigations which it is one of the purposes of this paper to describe.