372 



A, W. Eioell — Rotatory Polarization. 



In the final; vertical form of apparatus the lower clamp conld 

 be freely suspended from the jelly tube, simply guided by the 

 ring i, and the twist was applied by the cords x, great care 

 being taken to have them horizontal. 



Change of Length (m.m.). 



The following readings show that compression and elonga- 

 tion have no appreciable effect on the natural rotation. 



Aug. 5. Tube C 5. 



Change of length .... 1*7 3-6 

 Position of analyzer 



-1-1 



87 86 87 



3'3 



86 



