270 



IRRIGATION FABMINO. 



ized, which is a disadvantage, or not, according to the 

 character of the solids present. 



There are three systems of well boring employed in 

 artesian work. For shallow wells the spring pole is the 

 cheapest means as well as the slowest, and is often re- 

 sorted to by a farmer desiring to dig his own well at small 

 expense. A more pretentious outSt is such a one as is 

 shown in Figure 86. In this machine the band wheel 



FIG. 85. ARTESIAN WELL. 



is turned by a belt from the engine. When drilling 

 elliptic gears revolve, which raise and lower the drill as 

 the hole is deepened. A hand wheel having a worm is 

 turned to unwind a rope on the drum that lowers the 

 drill. The elliptic gears are engaged to the machinery 

 by a friction clutch, which can be engaged or disengaged 



