﻿by Change in Angular Velocity. 11 



been retained, for the constraint will be still further reduced 

 and greater irregularity is possible. 



It is particularly noticeable that as tlie constant rotation D. 

 of the cylinder is increased, the departure from theory becomes 

 more marked. 



Only three figures were obtained for the small cylinder, 

 because the agreement with the theoretical curves in the 

 three cases omitted will be practically exact. 



The curves for the " stopping " experiments show a much 

 greater departure from theory than the curves for the 

 "starting" experiments. This is due to the break-up of 

 the regular motion, owing to instability at the fixed outer 

 wall. Except with the high speed and the large cylinder, 



