VERTICAL DRAINS 



125 



sinkhole, or a cavern in the underground rock, affords a splendid 

 outlet for a system of tile drainage. 



FIG. 60. Can any good thing come out of this marsh full of brush, cat-tails, reeds, and 

 rushes? (See Fig. 61.) 



Fia. 61. Corn that will fill the silo to good measure has been grown on the same marsh 

 as shown in Figure 60, after being properly drained. 



Now and then a drilled well, or one dug and filled with stones, 

 furnishes the only possible means whereby water in basins can be 

 drained out. Not all wells made for such a purpose prove success- 

 ful this one may fill with water, while another may bring to 



