The energy taken off on the motor shaft is close on 200 horse power, but varies according to the machines at work; the speed of the motor does not, however, vary more than 3 per cent., and the brushes need no adjustment. About 6 ft. of shafting is coupled on in line with the motor shaft, and an extra plummer block fixed at the end. This shafting carries at its extremity an additional 2 ft. pulley, the power being delivered by belting from these pulleys to two large pulleys on the main shaft.
The machines run by this transmission consist of the looms of Rieter & Co., of Winterthur; the large flour mill and lift of A. Millot & Co.; the flour milling machinery of Frederick Wegmann & Co., of Zurich; the brick and tile making machines of the Rorschach foundries; and the looms of Messrs. Houget & Teston, of Verviers, in the Belgian section. A 15 horse power two-pole Oerlikon dynamo is also run by a belt from the main shaft, and generates power to drive a motor of similar type in the Swiss section of the upper gallery. This runs a length of countershafting supplying power to three silk-weaving machines constructed by Benninger Frères; six weaving machines from the Ruti works, near Zurich; and one knitting machine exhibited by Edward Dubied & Co., of Couvet.
The dynamo and motor are connected to the main cable by switches of the type shown in Fig. 5. These are specially designed to destroy the extra current on breaking circuit by the formation of an arc which gradually increases the resistance till the break occurs, rendering it less sudden. One wire passes through the handle and makes contact with the springs, and the other is attached to the clamp in which the carbon rod is held. The current is made to enter at the carbon rod, so that the arcs formed cause consumption of the carbon. A magnetic cut-out--Fig. 6--is also provided to each machine; this consists of an electro-magnet, through which the main current passes, provided with side pole pieces. A flat soft iron plate armature is hinged so as to come up against the pole pieces when attracted. When the current is not sufficiently strong to cause the plate to be attracted, a hole in the center of the latter engages over a small projection in the top of a weighted arm hinged in the center of the board, and keeps it upright. If now the current exceeds the limits of safety to the machine, due to a too heavy load being thrown on, the armature is attracted and releases the vertical arm, which falls over and enters with considerable force between the two spring contacts below. These contacts are connected to the field terminals, which are, therefore, short-circuited, and prevent the dynamo generating any current. A retractile spring can be adjusted to cause cut-off at any required current. These details are indicated in our illustrations mounted on their respective switch boards.