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increase of frequency did not diminish 

 the weight of the transformers. Pro- 

 fessor Forbes had brought a diagram 

 showing the output from the Grosvenor 

 Station (Fig. 28), and he argued that the 

 transformers by themselves absorbed an 

 energy equal to four thousand lamps. 

 That was surely not to be taken as a 

 serious argument. The diagram was not 

 one of HP., but one of current sent out. 

 Now the current sent out of course 

 depended on the lamps which were ' 

 alight. The argument was that in the 

 early hours of the morning there were 

 no lamps on circuit. But that was not 

 so certain. In the case of stations sup- 

 plying electric light by contract, for a 

 fixed rental without a meter, people were 

 wasteful with the lamps and allowed them 

 to burn all night long. Professor Forbes 

 had overlooked one important circum- 

 stance, namely, that if the transformers 

 were on the circuit without giving off 

 current to the lamps, there was a lag of 

 70°, 80° or more between the terminal 

 electromotive force and the primary cur- 



