VARIOUS GENERATORS OF ELECTRIC LIGHT.
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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
FIG.
lower part.
The inducing
18.
system was therefore represented by the two flat horizontal B', and the induced armatures were placed at the ends
coils B
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;
supplied the current for the light. collected,' as in Wilde's machine, by a'
shown
in the figure.
and the other bobbin These currents were means of the springs