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He was aware that he was disagreeing 

 with Professor Forbes on that point. He 

 hoped Mr. Atkinson would be able to 

 supply some particulars as to time lag, 

 that he would run the machine at differ- 

 ent speeds and give the results. The 

 kind of time lag mentioned by Professor 

 Ewing was well known to dynamo 

 makers, and the phenomenon was fa- 

 miliarly known as "creeping up." A 

 new machine sometimes took twenty 

 minutes to reach its full excitation. 

 Messrs. Crompton & Company were 

 making experiments on the important 

 question of loss of power in iron in 

 alternate-current work, which he hoped 

 would be published. The question of 

 hysteresis concerned transformers as well 

 as dynamos. He thought that most 

 people used bad iron. In testing iron 

 for direct-current machines they only 

 thought whether, with a given excitation, 

 they could get iron highly magnetized. 

 That was not the important question in 

 alternating currents. The question of 

 hysteresis must be considered. There 



