552 



Mr. P. E. Shaw on 



Calibration work could not be done in the daytime ; tbe 

 working of a neighbouring factory caused a rythmic fluc- 

 tuation of the ring system. 



Table V. gives a rough calibration for the lever system 

 when the bearings were so placed that the leverage was 

 higher. Only approximate values were obtained, for these 

 leverages were never used in actual measurements ; but it 

 was interesting to find values for the higher leverages and to 

 see how nearly they agreed with one another. 



The highest leverage position gives for the value of one 

 disk-unit the value O'l /u,/jl, which is certainly small. 



Table V. 



Calibration results for the apparatus, using the levers in the 

 middle and high ratios. 



Ring 

 Creep. 



No. of 



Rings. 



Read- 

 ings. 



Diff. 



Ring 

 Creep. 



No. of 

 Rings. 



Read- 

 ings. 



Diff. 



1 ring in 



30s 

 contract. 



1 

 2 



36-2 

 9-8 



43-2 

 49-6 



26-4 

 536 



None 

 apparent. 



5 



5 



235 

 40 



40-0 

 9-3 



33-5 

 30-7 



1 ring in 



45s 

 contract. 



2 



49 9 



17-3 



52-6 





5 



93 

 27-1 



32-2 





2 



17-3 



17-5 



49-8 





5 



27-1 



47-1 



29-4 





2 



17-5 

 14-G 



52-9 





5 

 5 

 5 



477 

 136 



491 

 153 



15-3 

 325 



34-1 

 338 



32-8 



1 ring (mean of 9) 26'2. 



X 



•• 2 =2620 units. 



588 

 lumfc = 2^2620 W" 



=0-112 mi. 



1 ring (mean of 35) 6"46. 

 \ =646 units. 



589 

 1 umt = 2^646"W- 



= 0-45^. 



