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BELL SYSTEM TECHNICAL JOURNAL 



which the reactance was so small that 



CC 



7 was no different from 



Ci + C 



Ci to the order of accuracy of the determinations. The parallel capaci- 

 tance of R in the cases where single unit resistances only were used 

 could also be made negligibly small compared with C in some cases, 

 though the resistance values of R were in general considerably higher 

 than those of r, and it was therefore more difficult to secure very small 

 phase angles in the former. However, in a large number of the de- 

 terminations a shielded resistance box was used for R, its phase angle 

 was some 5 to 10 times that of the single units, and too large to neglect. 

 Accordingly d' can be eliminated from the formula for K for the 

 purpose of this investigation while C cannot. The formula may 

 then be written in the more simple form: 



K = 



1 



Ci - (C + C) 



(3) 



The nominal values of the first order quantities used in the actual 



determinations are shown in Table 1. In this table Q is the ratio of 



reactance to resistance of either of the total arm impedances r and C\ 



or R and C. 



TABLE I 



Nominal Capacitance and Resistance Combinations Used in 

 Determination of K 



K 



J_ 19}. 



uCir \ 



