on certain strong Clay Subsoils. 241 
Surface. 
The ploughed soil. 
A soil partaking of the character of the superincumbent cultivated earth 
and of the strong clay beneatli, and which will admit of percolation. 
A bed of tenacious clay, not full of water, but almost impervious, 
being the cause of the wetness of the land, rain-water not going 
into it. 
In this case the water will be found just above the tenacious 
clay, and it is a great error in draining to go deeper into this 
than to bury your tile or pipe with safety, unless this mass of 
retentive clav is within a foot or two of the surface ; then place 
your drain 30 inches or 3 feet, filling that portion in the retentive 
clay with some porous material, such as a grass sod or soil, for 
the purpose of at any future time deepening your soil by subsoil 
ploughing, trenching, &c. In proof that deep draining will not 
in all cases answer upon the weald clay, I quote the following 
letter : — 
Slaplelmrst, January 30, 1847. 
Dear Sir, — In reply to your favour of the 25th inst., I beg to say that 
the land in my occupation is for the most part very stitF, wet, and flat, 
consequently subjected fiequently to serious injury from wet seasons, to 
obviate which I have been draining about 200 acres on the farm upon 
which I reside, besides small quantities of other faims, perhaps altogether 
rather more than 300 acres, nearly the whole of which has been done on 
the clay soils of the Weald of Kent. I commenced by going: 2^ feet deep, 
and found it answer my expectations fully. Subsequent to this an opinion 
began to be entertained that deeper drains would be much more bene- 
ficial for our clays ; many advocated it and adopted it, some of which is 
said to have been successful, although I must confess I have never myself 
been an eye-witness to a single case in which deep drainijig has been suc- 
cessful upon wet stiff clai/s. Although my employment as a land asent and 
valuer gives me the greatest possible opportunity for observation, the 
gfeneral prevalence of the opinion induced me to go a little deeper than 
before, and in one field of between 6 and 7 acres, at the earnest request 
of my deep draining friends, I put in the drains near 4 feet deep and 33 
feet apart 4 years ago (this was in 1843): in consequence of the stiffness 
of the soil, being nearly all strong clay, it proved an entire failure ; and I 
have this winter drained it again about 30 inches deep, and am fully per- 
suaded that depth in land like mine is much the best, being wet from the 
rain that falls upon it, and not subject to springs. I have no doubt the 
water would after a time pass down to the deeper drain ; but it would do 
great injury belbre doing so. I should recommend the deep drains upon 
porous soils and land suiyect to springs, but on those soils on which there 
are no springs, which are wet from rain that falls on them only, and are 
not porous, it is next to madness, in my opinion, to drain them deep, say 
4 or 5 feet, as some contend for. Yours, &c. William Barnes 
W. B. Webster, Esq., &c. &c. 
Turning northward, we will pause at Norfolk to record the 
opinion upon the subject of draining deep upon strong clay of 
VOL. IX. R 
