Bare Wire for Resistance-coils. 



The values of the 100 ohm coils are: — 

 No. of Coil. 



1 



2 



3 



4 



5 



6 



7 



223 



9 



April 5. 



April 6. 



100-511 



100-510 



100-967 



100-971 





100-266 



100-300 



100-305 



100-362 



100-365 



100-671 



100-676 



100-603 



100-607 



100*434 



100-435 



100-845 



100-850 



The 100 ohm proportional arms were determined by the 

 same method as was used for the 100 ohm standard coils. 

 Their values are : — 





April 17. 



April 20. 



April 21. 



Mean. 



100 in X 



. 100-224 



100-219 



100-220 



100*221 



100 in Y 



. 100-312 



100-314 



100-309 



100-312 



The 1000 ohm coils were also measured on the box itself. 

 In the gap A (fig. 4) was placed the 100 ohm standard coil ; 



Fig. 4. 



ioo Ohm 

 standard 



this, together with the first four dials, formed one arm of a 

 Wheatstone bridge ; the two other arms were the 100 ohm coils 

 in the proportional arms. A single flexible lead connected 

 the last coil of the 100 dial with any required coil on the 

 1000 dial. Another lead connected the other terminal of the 

 coil to be measured to the terminal of the proportional arm Y. 

 The current was provided by two storage-cells. 

 The values of the 1000 ohm coils are : — 



