94 ON DRAINING, 



■\vitliout reg-ard to systematic rotation, may be produced, and 

 ■vvitliout the aid of manure, for many years. 



But the -whole of this land is much too wet; it is too salt; 

 and its powers will not be appreciable until after deep and 

 complete under-draining-. It appears, however, that the 

 lands Avarped at a greater distance from the mouth of the 

 river, must be skilfully treated in respect of imder-drainage. 

 A complete power of deep under-drainag-e should be estab- 

 lished, to withdraw the water, and keep it down low beneath 

 the surface when injurious, whilst there should be provided 

 means of sustaining- vvater nearer to the surface and to the 

 roots of plants, when imder the influence of such a dry 

 season as was experienced in 1844. 



In many of these warped lands means exist to fulfil this 

 end, as water is raised out of the ditches by machinery when 

 in excess, and the height of water in the ditches is maintain- 

 able by drawing- it from the high land drains. A farmer, 

 i-esiding- near to Hatfield Chase, informed me that he con- 

 sidered he saved crops of the value of 1500/. in 1844 (when 

 it will be remembered we had fourteen Aveeks of hot sun, 

 without a drop of rain), by his command of water to charge 

 Lis ditches. The warped lands are very commonly divided 

 into fields of 10 acres, being squares of 220 yards, surrounded 

 by open ditches, and it is considered that the water is tho- 

 roughly drawn out of the soil to the level maintained in the 

 ditches ; but this I much doubt, and am satisfied from my 

 observation of these flat warped lands, both in wet and dry 

 weather, that they would be astonishingly benefited by a 

 system combining both sub-drainag-e and sub-irrigation ; but 

 it is possible that the farmer may have reason for not drain- 

 ing this soil more deeply or more completely, unless means 

 are pi'ovided for sub-irrigation in droughty seasons. 



There has been rather recently introduced by some drainers 

 a practice of making what they term air-drains, with the 

 view of providing for a ventilation of the soil, and also for 

 promoting, as they think, a freer flow of water from drains. 

 As regards the latter point, it is quite certain that such air- 

 drains mxist be superfluous and unnecessary. The fact of 

 ■water entering subterranean drains at all is quite decisive as 

 to the imiversal presence of air in soil, and no one has shown 

 or has attempted to show, so far as I know, its insufliciency. 

 Water could no more issue from a drain laid in the earth, 

 than it could flow from a tight barrel, if air did not press on 

 the surface of the liquid within it. Every one knows how 



