278 IRRIGATION FARMING. 



three feet long and sharpened at one end is provided, to 

 pass through the iron ring at the point of the canvas. 

 The device is shown in Figure 89. In use, the ends of 

 the stick rest upon the banks of the lateral, the iron rod 

 through the ring with the top slanting in the direction 

 of the water source and the sharpened end thrust to a 

 good depth in the earth at the bottom of the ditch. 



The author has used (many years ago, however) a 

 metallic dam consisting of a sheet of galvanized iron 

 about thirty inches long and fifteen inches wide and having 

 two rounded corners. There was an aperture four by 

 ten inches square in the center, for the water to flow 

 through. When the gate was in position the flow of 

 water through the aperture was regulated by a sliding 

 adjustable gate, made also of galvanized iron, easily 

 moved up or down by hand. The dam was set in 

 position across a lateral by crowding its sharp edges 

 down into the soil to the proper depth, thus forming a 

 check to the flow of the water in the lateral except as it 

 passed through the sliding gate. 



A Water Gate. Of all the flood gates, patented 

 or otherwise, there is but one that is worth building. 

 This gate is called the Carlisle gate, as a man by that 

 name invented it. Suppose a canal is sixteen feet wide ; 

 drive three good six-inch posts into the bottom of the 

 stream one on each side, and one in the middle ; make 

 a water gate just as if intended to swing it to a pole the 

 old-fashioned way. Then fasten the gate to the stakes 

 at the bottom with strap hinges, or if cheapness is an 

 item, with wires, then prop it up so that it will stand 

 erect against the common stream, but so that high water 

 will wash it down where it will lie, letting the drift go 

 over, but will not carry the gate away. The stakes or 

 posts at the bottom should be driven clear down to the 

 bottom of the stream, or the water will make a whirl 

 around them and finally dig them up. If the stream is 



