172 THE CULTURE OF FARM CROPS. 



the top being made of strips nailed across, so as to form 

 many crevices for the entrance of the water. By extend- 

 ing the end of one board a foot past the end of the other 

 the laps in the drain may be joined firmly. These drains 

 are placed with the narrow part down, by which the flow 

 is made more rapid and the deposit of sediment in avoided. 



The outlets of the drains should be amply large to avoid 

 back w r ater and should discharge if possible above the level 

 of any high water. If in time of freshets or floods water is 

 backed up into the drains, or there is any danger of it when 

 making the outlets, it is advisable to fit a gate to the outlet, 

 so that when tile water rises it may be closed against the 

 entrance of sand or mud, and opened when the water has 

 subsided, so that the discharge may be rapid and carry off 

 any sediment that may have settled in the drains. 



In plowing drained lands, the open furrows should never 

 be made over drains, lest the water lying in them should 

 find its way down and make a channel through the soil by 

 which sand or mud may be carried into the drain. The 

 location of every drain should be marked by permanent 

 stakes or posts in the fencee so that it can be reached when 

 desired without difficulty. 



