400 IRRIGATION FARMING. 



to the machinery by a fridlion clutch, which can be 

 engaged or disengaged while the machinery is running 

 or the tube is being rotated. A pump is operated by 

 steam, which forces water down the tubing to wash out 

 the cuttings. Expansion drills are, without doubt, the 

 best thing that can possibly be used for sinking wells, 

 as they cut a large hole below the casing, so that the 

 casing can be inserted more easily than can be done by 

 any other means. 



The most substantial outfit, and one that must be 

 used in very deep borings, is the old-fashioned Penn- 

 sylvania oil derrick. This rig is of a more permanent 

 charadler than the portable machine, and in setting it 

 up the posts must be well anchored. A walking-beam 

 is necessary, and this is operated by crank power. A 

 bull-wheel must be set in position to raise and lower 

 the tools, a sand-pump is necessary, and the drilling is 

 done by a man who attends to the temper-screw, which 

 rotates the drill-bit and prevents it from striking twice 

 in exac5lly the same place. 



The Uphill Siphon. — Sometimes farmers owning 

 water in reservoirs are desirous of using the water in 

 places which would necessitate what would be called 

 * * draining uphill. ' * Provided the land to be irrigated 

 lies lower than the surface of the water in the reser- 

 voir, this can be performed without any great effort 

 by using the principle of the siphon. A tile-layer once 

 agreed to drain a pond which at that time was full of 

 water, by laying the tile-drain from the pond over the 

 hill, no attention being given to the grade of the drain, 

 nor to the fac5l that the hill was three feet higher than 

 the water in the pond. He laid his line of tile about 



