Field Drainage. 4 1 



Undrained ground is less calculated to take in a store of 

 heat in summer than drained land, the summer sun being 

 wasted in drying up, by evaporation, the winter rain from 

 the soil, and in the process cooling down the land. 



Increased Value of Land from Drainage.— The actual 

 increased return from drainage must vary a great deal, accord- 

 ing to circumstances and the nature of the soil Numerous 

 cases were given in evidence before parliamentary committees 

 of rents being raised 50 to 1 00 per cent, after drainage. 

 The average of several different classes of soils showed a net 

 return of 10 per cent on the outlay. As a fair average it 

 may be taken that on clay soils a wheat crop will yield 

 one quarter to the acre more on drained than on undrained 

 land, and this without any additional seed or labour. In ^et 

 cold seasons the increase will be much greater, and the 

 drainage is often paid for by the extra produce of a single 

 season. 



After a series of years the subsoil of a thoroughly drained 

 field changes into the nature of soil as far down as the level 

 of the water in the drains, due to the ameliorating effects of 

 air and water producing healthy decomposition of the organic 

 and inorganic constituents. 



When the working of the land and the treading of the 

 horses is considered — a treading which in the case of a pair 

 of horses leaves more than 200,000 footprints when cutting a 

 9-in. furrow over an acre of land — and the effect of this in 

 puddling a wet clay soil and injuring its texture, the advan- 

 tage of freeing such a soil from surplus water may more fully 

 be estimated. Also by the penetration of roots and by their 

 ultimate decay in the subsoil, and by the working of earth- 

 worms, the texture of the soil is improved. The diainer has 

 not a better assistant than the worm. Worms work their 

 way down through dry soil to great depths. The author has 

 seen worm-holes at depths of 10 feet and 12 feet below 

 the surface ; and in a drained soil their burrows always extend 



