﻿in the Emission of Positive Thermions from Salts. 145 



exhibited by the curves, fig. 1. It will be seen that the first 

 effect of" increasing the pressure is a slight scattering of the 



Fig. 1. 



ions by collision which results in a lowering and broadening 

 of the curves. As the pressure is further increased this 

 lowering and broadening becomes more marked. Before the 

 curves are completely flattened out the gas also begins 

 exerting an appreciable effect upon the value of 2#, the 

 distance between the peaks. The gas interferes with the 

 Phil Mag. S. 6. Vol. 23. No. 133. Jan. 1912. L 



