4G2 THE HOME, FARM AND BUSINESS CYCLOPEDIA. 



that are perfectly dead level ; but the fall on contiguous pieces of ground, 

 if taken advantage of, is generally sufficient to make water run. The 

 plan to adopt, therefore, in draining long level flats of country, is, to go 

 far enough down the descent, and bring up a main level, so accurately cut 

 that no fall has been lost. This will, in most instances, give the required 

 facilities for getting rid of the water discharged by the under drains 

 which must then be formed. I may be told that this will be costly. 

 And so it will ; but in those districts where the value of the soil is kept 

 at a very low figure, when it might soon be largely increased by the re- 

 moval of stagnant water, the question of expense, or mutual arrangement 

 between neighbouring farmers in respect thereto, is not the primary one. 

 Only convince the owner of such land that it is quite possible to drain it, 

 and he will soon find out that the improvement can be effected, so as to 

 leave him ultimately a good profit on the undertaking. 



At all times, the aim in carrying out drainage works should be to give 

 at the first deep and suitable outfalls ; and afterwards, too much care can 

 scarcely be exercised in keeping the open ditches and outlets free from 

 impediment of every sort. Once let the chief outfall become gorged or 

 ineffective, and, of necessity, the whole drainage works are likely to suffer 

 damage. 



DEPTH AND DISTANCES APART OF DRAINS. 



We have yet to find out how deep and how far apart the drains require to 

 be in ordinary cases, to afford complete drainage. It is difficult to deter- 

 mine how deep the roots of most species of our cultivated plants will go, 

 if unobstructed by noxious water or impenetrable layers of clay. Ex- 

 perience has proved that the roots of cereals and clovers will descend at 

 least three feet into a porous good subsoil, and mangold -wurzel extends 

 its fibres to a distance of four or five feet in all directions. There is, there- 

 fore, no exaggeration in taking three feet as the depth to which all culti- 

 vated soils should be dried. If it is supposed that drains three feet deep 

 will be sufficient to secure this end, the sooner the impression is given up 

 the better. In all cases, the law of capillary attraction conies into opera- 

 tion, and limits the action of the drains by at least six or eight inches. 

 When one puts the edge of a piece of blotting paper into water, the effect 

 of this attraction or imbibition is very well seen. Now, in the soil the 

 same process goes on, only the earth and clay are less bibulous than the 

 paper, and draw up the moisture to a comparatively limited extent. The 

 same law may be observed in operation when we fill a series of small 

 tubes with water. In the tubes which have the largest calibre say that 



