ELECTFJCAL MEASUREMENTS 337 



Resume. Summing up the results deduced in this paper, it is seen 

 that the methods for the absolute determination of self-inductance 

 and capacity do not give as concordant results as could be wished. The 

 irregularity of results was caused, in the most part, both in the deter- 

 mination of self -inductance and capacity by the variation of the periods 

 of the currents used in the experiments. As the period enters directly 

 into the determination of self-inductance and capacity, all variations 

 of the period will appear in the results. The determination of capacity 

 is complicated by the presence of electric absorption (p. 323 et seq.). 

 The effect of electric absorption is shown to be that of an added resist- 

 ance in series with the condenser, called absorption resistance. A 

 direct method is given by which absorption resistance can be measured 

 (p. 319), and experiments are given which show that when condensers 

 possessing absorption are in series or in parallel, their absorption re- 

 sistances act under these conditions as ohmic resistances in series with 

 the separate condensers (p. 323). Absorption resistance is also found 

 to be extremely sensitive to temperature. 



The methods for the comparison of two self-inductances or a self- 

 inductance and a capacity are independent of the period, and when the 

 self-inductances are of different magnitudes the comparison can be 

 made with an accuracy of 1 part in 10000. These methods, therefore, 

 give a means of comparison of a self-inductance with a standard self- 

 inductance, or a capacity with a standard capacity to an accuracy of 1 

 part in 10000, or they allow the establishment of standards. 



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