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made with a large number of pole- pieces. 

 The Mordey machine had two ; in the 

 old type each pole-piece had its magnet- 

 izing coil, and there was great waste of 

 energy. Mr. Mordey had introduced 

 the idea of using a single coil to magnet- 

 ize the whole machine. Professor Forbes 

 had been experimenting a little in that 

 direction, and had thought it might be 

 worth while to exhibit a rough diagram 

 of a design, of a somewhat similar kind, 

 in which not only was a single coil used 

 for the magnetizing circuit, but a single 

 coil was also used for the induced circuit 

 (Figs. 27). The induction through the 

 radial parts of the field magnet was con- 

 stant. To prevent heating, it might be 

 necessary to subdivide the iron at the 

 pole-pieces into circular sheets ; but that 

 would be seen when the first machine 

 was made. That type of machine was 

 certainly of interest, and might prove of 

 value. The Parsons machine seemed to 

 him to fulfill the requirements of an 

 alternator better almost than anything 

 else which had been produced. It also 



