THE IRRIGATION AGE. 



233 



MEASURING THE FLOW IN UNDERGROUND 

 STREAMS. 



In mountain regions, and especially in California, 

 rivers often rise among the mountains, flow for a dis- 

 tance upon the surface, and then suddenly disappear. 



In an interesting paper read before the Western 

 Society of Electrical Engineers, Professor Slichter dis- 

 cussed the flow of water through the ground, and the 

 apparatus used for measuring the rate of flow. Meas- 

 urements was made, among others, upon the Rio 

 Hondu and the San Gabriel rivers east of Los Angeles, 

 Cal. Rising in a canon they flow above the ground 

 to its mouth, and then disappear for ten miles. Rates 



FIG. 1. 



of underflow of from 3.8 feet to 48 feet per day were 

 found, says Papular Mechanics. 



The measurements were made between drive wells 

 sunk for the purpose. Common li/2-inch or 2-inch 

 drive well pipe is used, having on the end an ordinary 

 1%-inch brass jacket well point from forty-two inches 

 to forty-eight inches in length, with a brass gauze 

 strainer. The pipe is cut in lengths of six or seven feet, 

 threaded 1%-inch at each end, wrought iron recessed 

 couplings being used to fasten the lengths together for 

 different depths. Rolled steel shafting four inches long 

 with a hole for the escape of air is screwed on the 

 upper end of the pipe for a driving head, and a heavy 

 cylinder 5% feet long by 5% inches in diameter with 

 iron rings shrunk on the ends is used to drive the pipes 

 down. 



Pig. 1 shows the way the drive wells are located, 

 AC being the probable direction of the flow as deter- 

 mined by the slope of the land. For deep work the 

 wells are put farther apart to throw out any mistakes 

 due to driving the wells not plumb. 



In Fig. 2 two wells, say A and D, are electrically 

 connected as follows: On the pipe D is a binding 

 post from which a wire runs to an ammeter, A, for 

 measuring the current; then the current runs through 

 a battery of five or six dry cells and to the binding post 

 on the case of well A. Inside the well D is a %-inch 

 nickled brass rod, four feet long, kept from touching 

 the well case by wooden spools. From the upper end 



of this rod a rubber covered wire connects with the 

 wire from the casing on well A as shown. In every 

 group each of the down stream wells is connected, as 

 just described, to the upstream well A. 



To find how fast water is traveling through the 

 soil from A to B, C and D, a pail of water into which 



FIG. 2. 



all the sal ammoniac it will dissolve has been placed 

 is poured into the well A. It will flow toward the 

 B, C and D and being a conductor of electricity, when 

 it reaches any one of the three wells it will form a 

 circuit between the casing and the nickle bar, and a 

 current from the battery will at once swing the am- 

 meter needle well up on the scale. The distance from 

 A to each down stream well being known, this divided 

 by the time elapsing between putting sal ammoniac in 

 well A, and the swing of the ammeter needle, will 

 give the rate of underflow. 



Finely powdered sal ammoniac may be used in 

 well A, lowering it as in Fig. 2 by a wire screen bucket 

 holding about two pounds. The method succeeds using 

 only common pipe and wiring between the casing of 

 up-stream and down-stream wells, leaving out the 

 nickled rod. 



Special clock work and self recording instruments 

 have been made which measure the slowest and fastest 

 flows yet found, so that after the wells are driven, 

 wired, and salted, the observer need not be always pres- 

 ent. A No. 2 cast iron pipe puller and five-ton rail- 

 road jacks will serve to pull the well casings when 

 through. 



A publication, interesting alike to the engineer and 

 layman, is the new catalogue on Hydraulic Rams, re- 

 cently issued by the Columbia Engineering Works of 

 Portland, Ore. It is replete with facts and figures 

 which demonstrate the superiority of this device over 

 the old fashioned ram; a superiority imparted to it 

 by a very ingenious valve mechanism fully described 

 in the catalogue. The most interesting feature of the 

 latter is the disclosure that by virtue of the peculiar 

 construction of the waste valve the shock so pronounced 

 in old style rams is completely subdued, making it pos- 

 sible to increase the size and capacity of single units 

 to mammoth proportions. This feat, formerly consid- 

 ered impracticable, raises the Phillip's Hydraulic Ram 

 from the level of what might be termed a cut and dry 

 mechanism to that of a highly scientific hydraulic en- 

 gine, which, owing to its great efficiency, inexpensive 

 operation and comparative simplicity, will fill a long 

 felt want in hydraulic engineering. 



The catalogue contains fifty-four pages, each of 

 which is covered with interesting reading matter. It 

 can be had for the asking. 



! 





 ! 



X 



Send $2.50 for The Irrigation Age 

 1 year, and The Primer of Irrigation 



