220 



Mr. F. W. Burstall on the Use of 



No. of 





















Coil. 



Jan. 12. Jan. 20. 



Jan. 22. 



Jan. 24. 



Jan 25. 



Jan. 26. 



Mar. 11. 



Mar. 14. 



Mean. 



1 ... 



•10067 



10071 







•10065 



•10065 



•10073 



•10073 



•10073 



2 ... 



•10012 



10012 



•10009 



■10008 



•10008 





•10012 





•10010 



3 ... 



•10067 



10069 



•10063 



•10061 



•10063 





•10050 





•10050 



4 ... 



•10008 



•10014 









•10011 



•10010 





•10011 



5 ... 



•09976 



09974 



•09975 





•09973 



•09972 



•09975 





•09974 



6... 



•09982 



•09987 







•09985 



•09985 







•09985 



7 ... 



•10046 



•10046 







•10042 









•10045 



8 ... 



•10003 



•10004 









•10003 







•10003 



9 ... 



•10055 



•10061 









•10066 







•10061 



It will be noticed that, in coils 1 and 3, I have rejected 

 certain values determined on dates before March 11 ; the 

 reason being that, when the new flexible leads were attached 

 in February, these two coils were touched and slightly bent, 

 and had in consequence to be re-annealed. 



The values of the 1 ohm coils are — 



No. of 

 Coil. 



1.... 



2.... 



3.... 



4.... 



5.... 



6.... 



7.... 



Jan. 8. 

 •99929 

 •99956 

 •99569 

 •99964 

 •99776 



9 



Jan. 11. 

 •99929 

 •99956 

 •99568 

 •99969 

 •99774 



1-00007 

 •99976 

 •99878 



Jan. 26. Feb. 12. 



•99970 



1-00007 

 •99979 

 •99875 



•99978 

 •99875 



Feb. 16. 

 •99931 



1-00053 1-00051 



1-00008 

 ■99980 

 •99878 



1-00053 



Mean. 

 •99930 

 •99956 

 •99568 



•99975 



1-00007 



•99978 



•99877 



1-00054 



Values of the proportional arms are- 



linX 

 1 in Y 



April 3. 



•99863 



•99645 



Mar. 8. 

 •99860 

 •99641 



Mar. 16 

 •99860 

 •99642 



Mean. 

 •99861 

 •99643 



Considerable trouble was experienced in the determination 

 of the 1 ohm coils in the proportional arms, owing mainly to 

 variations in the resistance of the plugs, which were fitted into 

 the usual divided blocks. The amount of this error is of 

 little moment when compared with the 10 ohm coil. The 

 1 ohm coils have not been employed in the determination of 

 the larger resistances. 



The values of the 10 ohm coils are : — 



