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286 suitably pivoted. This is well illustrated in the case of the Krièger or Postel-Vinay motor, fig. 7, designed by M. Cuènod, which is in general use on the Krièger vehicles, and has in consequence become generally known as the Krièger motor. This motor has four poles with four flat coils,. Each of the coils on each of the poles is of a twofold composition, being partially a thick wire winding designed for use as a series winding, and partially a thin wire winding designed for use as a shunt winding; the Krièger vehicle, as we shall subsequently show, using the motors sometimes as series motors, and sometimes as shunt motors, according to the conditions



of running. The motors, which are pivoted, and swung on springs, are provided with only two brushes,. It might be supposed that, having four poles, four brushes should have been provided, and some of the original four-pole motors were so constructed. It was shown, however, by Mr. Mordey that by connecting the opposite wires on an armature in parallel with one another two brushes only might be employed instead of four. Electrically this is of course the same thing as using four brushes and cross-connecting them.

Other types of motor have also been employed successfully for the propulsion of electromobiles. Noticeable amongst