For operating and controlling the above-described steering apparatus, and indicating the position of the rudder to the operator on shore, the following devices are employed, in combination with the pole changers _s_^{2}, _s_^{3} on the keyboard:--The pole changers are geared together by insulated toothed wheels, which are fixed on the spindles or axes of the said pole changers, so that the latter work accurately together and maintain the same relative positions to each other. The pole changer _s_^{2} is connected by one of the said insulated cable wires with a shunt on board the boat, which shunt is connected with a set of magnets arranged in combination with the valve of the engine that drives the steering apparatus, and which valve is reversed or opened and closed by the reversal of the currents through the said magnets, as above described, and the said engine moves the rudder to port or starboard at the will of the operator. In order that the operator may know the exact position of the rudder at any moment, a series of pins or projections fixed on an arc or other portion of the rudder stock, and arranged in combination with an insulated spring projecting into the path of the said series of pins, are employed. This spring is connected by one of the cable wires with the pole changer _s_^{3} on the keyboard, which is geared with and moves in unison with the pole changer _s_^{2}, so that the electric current that controls the steering engine, and the current that returns the indication of the rudder's position, will both be reversed simultaneously. A separate battery is connected with the index on the said keyboard, whereby a constant current is maintained between this index and the indicating apparatus on the boat. The current passing from the said spring to the shore is made to indicate the position of the rudder by the index on the keyboard by the contrivance shown in Fig. 129. This contrivance consists of a set of magnets _w_, which have a vibrating armature _w_^{1} pivoted to oscillate between them. One end of the armature lever is provided with insulated spring pawls _w_^{2}, which take into ratchet wheels _w_^{3}. On the same shafts on which these ratchet wheels are fixed are wheels _w_* formed with insulated teeth and geared with each other. The shaft of one of these wheels is geared by bevel pinions _w_^{4} with a vertical shaft _w_^{5}, to which is attached the index needle or finger _x_**, Fig. 128. Therefore it will be obvious that this index finger is placed in connection with the aforesaid spring and series of pins attached to the rudder yoke on board the boat.