THE DRAINAGE OF GRASS LAND 13 



by the drains. This accounts for the necessity of apply- 

 ing lime from time to time on drained land which happens 

 to be deficient in it. But while ammonia — which, by the 

 process known as nitrification, becomes oxidised into nitric 

 acid, and, entering into combination with lime, forms nitrate of 

 lime — may possibly be wasted, it is satisfactory to remember 

 that superphosphate of lime and other forms of phosphoric 

 acid are never thus lost. Nor does it appear that potash is 

 easily abstracted, so that there need be no hesitation in apply- 

 ing these substances from fear that they will be carried away 

 by the drains. 



It may be accepted as a general truth that grass land 

 should not be drained so deeply as arable land. The weight of 

 engines and heavy agricultural machinery has not to be allowed 

 for, and there is no doubt that grass can advantageously absorb 

 more moisture than corn crops. Further, the roots of most 

 grasses do not penetrate very deep, and therefore it is desirable 

 to have the water somewhat nearer the surface than on the 

 arable part of the farm. 



As to the practical part of draining I need say but little. 

 There are tracts of country without any arterial drainage, 

 no river or stream being available into which drains, if laid, 

 could discharge their effluent water. The remedy is of 

 course beyond the power of private individuals, except in 

 a few rare instances. Such works can only be carried out by 

 Government, or by companies with large funds and under 

 parliamentary sanction. This subject will, however, one day 

 claim more attention from statesmen. Scientific engineering 

 has rendered the task possible ; the real difficulty lies in 

 its cost. Meanwhile, in such exceptional districts, pastures 

 having no fall for drain-pipes may be considerably improved 

 by a system of gutter-cutting on the surface. This practice 

 would often be serviceable on land subject to floods. Water 

 should not be allowed to lie on portions of a field after the 



