DRAINAGE. 125 



plain of some extent. The steep ground had a subsoil of 

 seraiporous marl, was not drained, and showed little sign 

 of wet. The drains in the lower land were in the line of 

 its descent, and were driven well into the point where the 

 steeper rise commenced. In this ground we sunk four trial- 

 holes at points equidistant from the drains, and in their 

 direction. The appearances disclosed by three of these holes 

 were not satisfactory. The water-table was less lowered 

 than in the previous case, and even after they had been 

 opened and exposed to a dry wind for some days, their 

 faces, and that which fronted the hill in particular, re- 

 mained dark and damp, and water was evidently squeezing 

 through them. In the fourth trial-hole the water-table 

 stood several inches lower than in the other three, and all 

 its faces exhibited the cracked appearance which is usual 

 in well-drained land. About 3 yards from the upper end 

 of this fourth trial-hole a deep drain passed between it and 

 the hill. The inevitable conclusion appears to be, that, in 

 land so situated as we have described, some sort of cutting 

 off drainage is essential to a perfect cure. A single deep 

 drain passing under the hill, at the point where the steeper 

 rise begins, may not be effectual, because, whenever its 

 depth (be it 4, 5, or 6 feet) is exhausted by the fall of the 

 land, the water from the higher ground having passed 

 under it will appear at the surface. We are about to drain 

 some land similarly circumstanced, and we have set out 

 the drains in the direction which a collier expressively 

 calls half-rise, bisecting the right angle formed by the line 

 of steepest descent and the horizontal line. We hope by 

 this compromise to secure, with respect to every portion of 

 the land drained, most of the advantages of a drain in each 

 of these directions. 



The late Sir K. Peel took an interest in the reprint of 

 this Essay. On the morning of the day on which he made 

 his last speech in the House of Commons, he addressed a 

 letter to us on the subject of the reprint. We cannot, 

 indeed, we know not why we should, deny ourselves the 



