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the direct-current dynamo the term self- 

 induction had been a sort of scapegoat 

 for all sorts of vague notions. Even 

 now, in the case of direct-current ma- 

 chines, people talked about the self- 

 induction of the armature. Of course 

 there was no such thing in direct-current 

 machines, and the idea was an absurdity. 

 In alternating currents, the same accusa- 

 tion could not be brought, as the whole 

 armature current varied. With regard 

 to motors, he thought the author's ideas 

 were a little elementary for the present 

 day. With a big motor, running at dif- 

 ferent loads, it was found that the 

 efficiency was extremely small if depend- 

 ence was placed simply on self-induction 

 to keep the motor and dynamo in step. 

 He did not think that motors which de- 

 pended on self-induction for keeping in 

 step would answer. Many seemed to 

 think the chief difficulty was to start the 

 motor. This was really a small matter. 

 All that had to be done was to make a 

 self- exciting motor. Take the commuta- 

 tor machine made by the Thomson- 



