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ample space and cooling surface could be 

 provided, and from which it could be 

 easily removed when not required, that 

 was when it was only necessary to run 

 one machine. The armature was the 

 very worst place for iron. He ventured 

 to think it was much the best to make 

 the armature stationary, as he had done. 

 It then had only to resist the tangential 

 drag of the field. He thought a great 

 mistake was made in some alternators in 

 using Pacinotti projections. In all cases 

 there should be, as nearly as possible, a 

 steady magnetic flux in the field. This 

 could not be done if projections were 

 used. The Zipernowsky and Parsons 

 machines were faulty in this respect. 

 Much had been said about the form of 

 the wave yielded by alternators. He had 

 some time ago made an experiment with 

 the first of his machines, using the 

 method which was now described by 

 Professor Ayrton, and found that the 

 curve had the form shown by Fig. 38, 

 which was almost a sine-curve. On the 

 subject of the lag in transformers, to 



