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BELL SYSTEM TECHNICAL JOURNAL 

 TABLE VI 



Agreement between Me.\surements on a St.\ndard Condenser Box on Three 



Different Bridges, All Calibrated by the Step-up Method, 



Using the Same Primary Standard 



•Ld? X 108 = 11215, 





X 10- 



a = .0014%, 

 2,a = .0042%. 



Note: d = per cent deviation from the mean value for any setting. 

 where n = the number of observations. 



w 



bridge was probably appreciably less than ±.005 per cent in all cases, 

 as the values of Table VI were obtained in the course of the routine 

 calibration of the several bridges, while in the determinations of K only 

 the one bridge was used and special precautions were taken to make 

 the consistency of the step-up as high as possible. In any event this 

 value of ±3a is appreciably less than that for a single determination 

 of K, which ranges from ±.010 per cent to ±.014 per cent, as shown in 

 Tables II and III. Accordingly the assumption that the consistency 

 of the step-up method of calibration is sufficiently high for the purpose 

 is well founded. 



The accuracy of the capacitance values is also dependent upon the 

 accuracy of the determination of the equivalent shunt capacitance of 

 the resistance R. The phase angle of the series resistance r was 



