14 



No. V. 



AN AUTOMATIC STOP MOTION FOR A 

 WATER MOTOR. 



Figure f. 



We use as a motor for working our pump one of Rams- 

 bottom's Water Motors, worked by the Town's pressure of 

 water, and in the tower-tank we have an arrangement for 

 stopping the motor when the tank is full, and starting it 

 again when down at a certain level. We have tried several 

 modifications of the principle on which the ball tap works 

 with varying degrees of success, until we arrived at the one 

 about to be described, which acts perfectly. 



A. is a wood float connected by an adjustable arm B. with 

 the lever C, which is supporced on the edge of the tank by 

 the pillar P. In use it was found that the float A., on being 

 forced up by the water, was liable to leave the side of the 

 tank, so that a double-jointed arm 1. 1., was fixed on the 

 opposite side to keep it in its place. E. represents the arm 

 which goes down to the tap, and F. is a weight corre- 

 sponding to that of the long rod E., so as to balance the 

 arrangement. As the float A. is forced up, of course, E. is 

 lowered to a corresponding degree, and would be gradually 

 shutting off the tap of the motor unless steps were taken to 

 prevent this being done until the tank was full. It will be 

 observed, however, that the arm B. is slotted at its upper 

 end, so that the float does not begin to press on the lever 

 until it has risen through a distance corresponding with the 

 length of the slot. A similar slot is made where the rod E. 

 is connected with the lever of the tap, and both these slots 

 are adjustable so that at the time the lever over-balances the 

 tank is full, and the time has arrived for the motor to be 

 stopped. This was done gradually at first, but it was found 

 that with a rotary pump, a time arrived when the motor was 

 working so slowly that the pump had not power enough to 

 lift the water the required height, and thus went on wasting 

 power until the level of water in the tank had been suffi- 

 ciently lowered to start the pump more vigorously. To avoid 

 this the present system was devised where, instead of having 

 an arm with a weight like F. directly over the fulcrum of the 

 lever C, a flat bar of iron G., about 2in. wide, is supported 

 over C. by two pillars, and turned up at both ends so as to 

 prevent the rolling weight H. from falling off. This weight 

 is made from a solid piece of iron and turned out in the 

 middle, so as to leave a flange hanging over G. on each side. 

 For further safety a light rod K. connects the two ends of 

 G., so that there is no chance of the weight H. falling off. 

 It will be seen that as soon as ever the lever C. is in the 



