VARIOUS GENERATORS OF ELECTRIC LIGHT. 73 



machines of Gramme, of Lontin, of Brush, of Biirgin, and of 

 Wallace Farmer have all availed themselves of it. 



Ladd's machine, represented in Fig. 18, was in a manner 

 merely one of Wilde's machines turned horizontally, with its 

 upper part replaced by a second system, having a rotating 

 bobbin similar to that of the lower part. The inducing 



FIG. 18. 



system was therefore represented by the two flat horizontal 

 coils B B', and the induced armatures were placed at the ends 

 a a', inside of the two iron standards N M, M N, composed of 

 two parts forming the polar armatures of the magnetic coils 

 B B'. One of the bobbins a, less than the other, was intended 

 to excite the inducing electro-magnet; and the other bobbin 

 a' supplied the current for the light. These currents were 

 collected,' as in Wilde's machine, by means of the springs 

 shown in the figure. 



