CONVICT LABOR FOR ROAD WORK. 85 



is to be placed; (8) the preference as to elevated tank, hydro- 

 pneumatic tank, or pneumatic-pump methods; (9) the kind of 

 power to be used (hand, gasohne engine, or electric motor); (10) 

 the nimiber of people to be served; (11) the approxioaate number 

 of faucets desired and an estimate of the amounts of water to be used 

 for various purposes; (12) the number of head of live stock of all 

 kinds. 



HYDRAULIC EAMS. 



When there is available in the immediate neighborhood of the 

 camp a spring or other supply of pure water so situated that a con- 

 siderable fall may be obtained within a reasonable distance, a hy- 

 drauHc ram may be used for pumping to the storage tank. The ram 

 is a simnle though wasteful machine, which utilizes the momentum 

 of a stream of water falling a small height to elevate a portion of the 

 water to a greater height; and once started the operation is contin- 

 uous until the valves become worn. 



The proper size of ram to suit any special condition is a matter 

 which should be taken up with manufacturers of rams. It will 

 depend upon the following factors: 



(1) The flow of Water from the source of supply, determined by the 

 time required to fill a vessel of known capacity; (2) the difference 

 between the level of the supply and the lowest point within a reasona- 

 ble distance suitable for the location of the ram; (3) the distance 

 between the source of supply and the proposed location of the ram; 

 (4) the difference in elevation between the ram location and the 

 highest point to which water is to be delivered; (5) the length of 

 pipe necessary to conduct the water to the point of delivery. 



In purchasing a ram, information with regard to the foregoing 

 factors should be sent to the manufacturer. 



The efficiency of a ram is governed by the ratio of the fall of water 

 from the spring to the ram to the height to which water is to be 

 pumped. It is greatest when this ratio is from 1 to 2^ to 1 to 3, and 

 the ram usually will not work well when the height to which the water 

 is to be pumped is more than 25 times as great as the fall from the 

 spring to the ram. 



The relation between the four interdependent factors, fall at the 

 ram, lift to the tank, the supply at the spring, and quantity of deliv- 

 ered water are expressed approximately by the following equation: 



„ QXH 



in which 



Q=supply of spring in gallons per minute, 

 11 = fall in ff'fit from spring to ram, 

 h=hoight of storage tank abovo ram in feet, 

 q=quantity of water piifnpod in gallons per minute. 



