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After University of Minnesota 



Fig. 289. Diagram of the operation of 

 the special two-chamber pump. There 

 are no pistons. 



Pneumatic system. The pneumatic system (Fig. 288) 

 consists of an engine or motor, air pump (compressor), air 

 tank, reducing valve, and a special two-chambered pump 

 (Fig. 289). This pump is 

 placed in the well, under 

 water. 'The compressed 

 air is piped to it. Water 

 may run into one chamber ; 

 when this is filled, a float 

 opens the other chamber 

 and allows the air to enter 

 the filled chamber and force 

 the water up the service 

 pipe to the faucets. While 

 one chamber fills, the other 

 discharges. The automa- 

 tically operated valves 

 cause a continuous flow in the pipes. If all faucets are 

 closed, no water can get out, so no air comes in. In this 

 system the water is pumped direct from the well to the 

 faucets. It is not stored. 



The shortcomings of this system appear when several 

 faucets are opened at one time, or when the pressure- 

 regulating valve is opened to make it possible to do lawn 

 sprinkling or buggy washing. When this is done, the air is 

 allowed to enter the pump proper more rapidly than the 

 water can enter. The action is so vigorous that the floats 

 hook up, with the result that no water is delivered at the 

 faucets. This system is a little more expensive than the 

 hydropneumatic because of recent patents on the special 

 pump. 



Hydraulic ram. A ram is worth consideration where there 

 is a good spring or creek, safe and clean, or a flowing well 

 below which a little slope may be found, together with an 

 oversupply of water. Figure 290, page 372, shows the parts 

 and principles of the hydraulic ram. From a source, G, the 



