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BELL SYSTEM TECHNICAL JOURNAL 



This little unit will pump water at the rate of over one barrel per 

 minute and discharge it through a hose away from the job to any 

 location desired. It will operate all day with practically no atten- 

 tion, upon a gallon or two of gasoline. When pumping under ordinary 

 conditions it will handle water faster than 12 men with hand pumps. 



One very desirable feature of the diaphragm pump is that it is 

 self-priming. For instance, if splicers are working in a manhole the 

 pump can be started and the initial volume of water removed, then 

 as seepage water enters the manhole it will be immediately taken 

 up and discharged without any attention from the splicers or helpers. 



Fig. 18 — Light Weight Centrifugal Pump. Capacity Seven Barrels per Minute 



For handling larger volumes of water there has just been developed, 

 as the result of careful study and cooperation with the manufacturer, 

 a new type of centrifugal pump shown in Fig. 18. This unit consists 

 of an air cooled engine similar to that used in the concrete mixers. 

 On the end of the engine shaft is mounted the centrifugal pump im- 

 peller. The pump casting also forms a base for the engine. 



As an indication of the capacity of this pump it might be of interest 

 to note that it would not be possible to get enough men with hand 

 pumps around a manhole to handle water as fast as this unit. It will 

 pump seven barrels of water per minute and mounted on skids as 

 shown it weighs only about 500 pounds. 



In the case of trucks which do a considerable amount of under- 

 ground cable placing in districts where water must be removed from 

 manholes in advance of the cable placing operation, centrifugal 



