Disintegration in a Vacuum Tube. 



423 



however, did not work at constant cathode-fall, and more- 

 over, as was first pointed out by Holborn and Austin, his 

 experimental numbers do not give much support to his- 

 statement. 



Kohlschutter, from the relative slopes of the disintegration- 

 cathode-fall curves at different currents, concluded that the 

 rate of disintegration for a given cathode at constant cathode- 

 fall is proportional to the current. These observations were 

 however, taken with relatively small currents and at high 

 cathode-fall, when the straight-line law between it and dis- 

 integration holds good. The authors have shown that in the 

 general case the relationship between disintegration and 

 current is more complex. Curves 3 show the results for 



Curves 3. 



f 6 * 



>v i 11 L a.+n./se yes 



a series of determinations with currents ranging from 1 to 

 7*5 m.a. and cathode-falls from 400 to 1000 volts. The 

 ordinates " D " are values of disintegration in milligrams 

 per half-hour. It is clear from these curves that as the 

 current increases the rate of increase of the disintegration 

 decreases. 



