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Houston Company, and put it on an 

 alternate-current circuit, it would start, 

 sparking badly at first, and eventually 

 synchronize. There was no difficulty in 

 starting the motor, but it would not 

 work efficiently. The author had asked 

 how it was that the ■ waste power was 

 greater in the armature conductors of a 

 machine without iron in the armature. 

 It was because the change of field was 

 more abrupt in that case. A great deal 

 had been said at different times about 

 the advantage or disadvantage of iron in 

 the armature, and it had been discussed 

 both from a mechanic's and from an 

 electrician's point of view ; but when it 

 was remembered that the air-space (in 

 spite of what Professor Forbes had 

 stated) was really the same whether there 

 was iron in the armature or not, it would 

 be seen that the whole question was one 

 of mechanical construction against elec- 

 trical efficiency. If there was iron, power 

 would be lost in the reversal of mag- 

 netization. If there was none, there 

 must be, to a certain extent, flimsiness. 



