ON STANDARDS FOR USE IN ELECTRICAL MEASUREMENTS. 



31 



. legal 



Appendix I. 



On the values of the B.A. standards of resistance greater than 1 B.xi. unit. 



The coils of approximate value 10 B.A. units marked Elliott Bros., 

 No. 6(j and No. Ql, or ^ 20 and 21 respectively, were compared with the 

 B.A. standards by the method described in the last report,' with the results 

 given ill the following table : 



Mark of cuil 



Elliott No. 06 

 ^ No. 20 



Elliott No. G7 



t.> 



No. '_n 



Elliott No. G8 



f^N. 



I Elliott Xo. ()',i 



I ^ No. 23 



Elliott No. 70 

 ^ No. 24 



Date 



July 5 

 July 7 



July 5 

 July 7 



July :.' 1 

 Anu-ust 11 



July 24 



August 11 



Elliott No. 7 



t.> 



No. 



Elliott No. 72 

 ^ No. 2(5 



Elliott No. 7;'. 

 ^ No. l>- 



July 2G 

 August 11 



July 20 

 August 11 



Valiic touiul ill 1)..\.TJ. 



lo-ooor. 

 loooi:! 



lOOOGO 



loooi:; 



]oo-(i;is 

 inoiin 



100-024 



10O'0!)7 



August 11 



9!)9'71l 

 1000-78 



9tt!)vSl 

 1000'7i) 



August 1 1 



10000-2 



i0(K>(;-'.t 



The coils were immersed in the water bath, the temperature of which 

 remained constant during each observation, for some days before the 

 measurements were made. 



The values thus found wore used for the determination of the coils of 

 higher resistance, the methods of the last report '-' being employed in this 

 case also. The insulation of the various parts of the apparatus was tested 

 carefully. Each result given in the table is the mean of two or more 

 determinations at the same temperature. The readings of the thermo- 

 meter used were compared witli those of a standard instrument. 



' r.. A. lloport 1883, p. 43. 

 ' 13. A. Report 1883, p. 44. 



