82 AGRICULTURE 



flow may be reduced to 400 yards, which 

 would mean a fall of 1 in 200, or twice as 

 much as formerly. 



It sometimes happens that fields which 

 slope upwards towards a hill are wet, owing 

 to the outpouring of water along the base of 

 the steep ground. One may often find a 

 series of springs, or, at any rate, moist spots, 

 along a certain level on a hillside, the water 

 being forced to the surface at these points, 

 owing to the dip and character of the strata 

 of which the hill is composed. If, for in- 

 stance, the strata dip towards the north there 

 may be springs along the north side of the 

 hill but none along the south side, the rain- 

 water, in fact, that falls upon such a hill 

 sinking down until it meets with some 

 stratum through which it cannot pass, and 

 along this stratum it will flow until it finds 

 its way to the surface on the north side. 

 Having gained the surface of the ground, 

 the water may then proceed to flow over the 

 fields immediately adjoining. Of course 

 such water can be got rid of by the ordinary 

 process of drainage, which consists in con- 

 structing parallel drains at comparatively 

 close intervals, and into these drains the 

 water will find its way. But it must neces- 

 sarily be relatively very expensive to drain 



