ALTERNATING CURRENT MEASUREMENTS. 



45 



voltages, and with care the unavoidable errors may be reduced 

 to one or two per cent, or even less. See a paper by H. W. 

 Fisher, Transactions of International Electrical Congress, Vol. II, 

 pages 294-312, St. Louis, 1904. 



Fig. 37. 



17. Transformer multipliers for alternating current instru- 

 ments. A given direct-current voltmeter may be adapted to 

 measure a high voltage by connecting a high resistance in series 

 with the instrument. Such a resistance is called a multiplier ; 

 it may be used with an alternating-current voltmeter (except the 

 electrostatic voltmeter). 



