240 
On the Failure of Deep Draining 
only lately, and the results may in some measure be different in 
another year; yet upon other portions of my land I have drains 
not exceeding 30 inches, which have acted perfectly for years. 
In another field I put some deep drains, and returned the clay on 
the tiles, and found in the spring, when I wanted to roll the 
wheat with Crosskill's clod-crusher, that on that portion of the 
field the land was not nenrly so dry, and the soil stuck to the roller. 
I may mention here that a railway cutting through my farm 18 
feet deep, drains no more land on each side of it than a drain 
3 feet deep. 
A neighbour of mine, the Rev. E. Tunson, of Woodlands, 
had several deep drains put on his farm many years ago. These 
drains continued open, but they ceased to act, and the land above 
them became so wet that it had to be redrained. The same may 
be seen on the estate of H. Holloway, Esq., at Marchnood; 
and also the Park at Norris Castle, Isle of Wight, where, though 
thousands have been expended in deep drains for springs, the soil 
being retentive, surface-draining is more wanted. This would 
not have been the case had the soil been of a porous nature : it 
arose from the fact that the water could not percolate through the 
clay-bed to the required depth. 1 found numerous other deep 
drains quite unobstructed, yet the land about them so wet that we 
did not know it had been drained ; for instance, at Thornhill near 
Southampton. And I remember Lord Portman telling me of a 
similar instance on an estate of his near Blandford. 
I wish to point to cases of the failure of deep drains, under 
those circumstances in which I have expressed myself opposed to 
their use, in many parts of England, and on various geological 
formations ; and I may as well, therefore, arrange them in some- 
thing of geographical order. From Hampshire, then, we will 
turn eastward and pass into Kent. We have heard much of the 
deep-draining on the weald-clay; like most other clays it varies 
greatly in its nature ; in some places it is of a very tenacious 
character on the surface, but as you dig into it, instead of be- 
coming stronger it becomes milder. In this case your drain may 
have a freer flow of water at 4 feet than at 2 or 3 ; because the 
water having, by however slow a process, percolated through the 
superincumbent mass, does not meet with a more retentive bed 
of clav at 2 or 3 feet, as on other soils ; but in other parts of the 
weald the arrangement will be found which is common with the 
clays of the London Basin — the oolite and lias. The section of 
the ground will then present soils in the following order : — 
