.1902. 



FORESTRY AND IRRIGATION. 



245 



A SIMPLE METHOD OF RAISING WATER. 



By Major Gilbert Thompson, 



U. S. Geological .Survey 



IN 1 87 1 , ^vhile surveying along the Po- 

 tomac River, at Washington, D. C, 

 I noted a simple method of removing 

 water from a place of excavation at the 

 river's bank. The space was inclosed 

 by a board piling, and at a point above 

 the highest tide in the river a dipping 

 trongh was placed, b>' which the water 

 had been removed from the excavation. 

 This will be best understood by the ac- 

 companying sectional diagram : a, the 

 board piling ; b, the trough, which was 

 made of pine boards nailed together 

 and open at one end, c. It was kept in 

 place by two cleats upon the under side 

 where it rested in the piling. I think 

 it was worked by an upright handle, 

 similar to the ' ' rockers ' ' used by miners 

 in placer mining, and probably a similar 

 contrivance is used by them to remove 

 water from trenches and excavations. 

 I have added a flat vah^e and a lifting 

 rope to give it a more general design. 

 A brief examination of the diagram in- 

 dicates that a number of arrangements 

 can be designed to work it ; a pulley 

 with a counterpoise or lifting weight 

 would be a practicable method. 



There are a great number of purposes 

 for which such a simple apparatus for 

 lifting water a short distance would be 

 very valuable. There is \&xy often a 

 pond, with good soil about it, which 

 could be cultivated for garden purposes 

 if water could be raised even one foot. 

 Reservoirs can be frequently constructed 

 in wet, marshy ground, affording a small 

 but useful suppl}' of water. 



I have computed by graphic methods 

 the following tables, which are accurate 

 enough to be suggestive and of value in 

 making an estimate of performance re- 

 quired. I have adopted a trough 10 

 feet in length from pivot point and i 

 foot square, so the values can be easily 

 adapted for other widths. It can be 

 readily perceived that if the end which 

 is submerged was made a bucket by 

 fastening a board on the top, that more 

 water could be raised at a single lift. I 

 have accordingly computed such values 

 for a bucket i foot, 2 feet, etc., in depth. 

 How far this is entirely useful depends 

 upon the fact that as the depth of sub- 

 mergence becomes greater the working 

 becomes much slower. It mav be re- 



1, BOARD piling; b, DIPPING TROUGH, OPEN AT C; d, CLOSED END AND LIFTING ROPE; 

 e e, CLEATS TO HOLD TROUGH IN PLACE ; d, FLAT VALVE ; i, INSIDE LEVEL, 



OR RESERVOIR ; (9, OUTSIDE LEVEL. 



