42 



On Draining. 



lutely invariable, inflexible, or unexceptionable. It will be my 

 business to show that, in the matter of depth at least, they are not 

 to be taken as rules pures et simples uniform under all 

 varying circumstances, and always rigidly applicable under the 

 same form. I hope to be able to convince my readers that there 

 are conditions under which a certain amount of deviation, or 

 rather perhaps of relaxation, may be admitted with advantage ; 

 and before I attempt this I may farther justify myself by stating 

 that I have not presumed to enter upon it without having allowed 

 a sufficient lapse of time to test my conclusions, however carefully 

 considered; and to ratify them, to the best of my judgment and 

 belief, by the only certain seal of practical success. 



I have executed my work here at various depths and distances. 

 In my first steps I was disposed to be cautious and empirical 

 rather than theoretical and hasty. I was comparatively un- 

 acquainted with the peculiar elements of my case. I had, of 

 course, many prejudices and misgivings to meet and to surmount; 

 and I was solicitous that my commencement should not risk a 

 failure of efficiency on the one hand, or on the other raise the 

 cost too high. I began, therefore, with drains of 3 feet deep and 

 8 yards distance. These appeared to be safe dimensions ; and I 

 found that in most cases they produced not an unsatisfactory re- 

 sult. I have a good deal of ground apparently well dried upon 

 this plan ; still it did not always appear to answer quite equally 

 well, even where the nature of the subsoil seemed to sanction it ; 

 and I was, moreover, not quite satisfied with the depth ; which I 

 had always considered rather as a minimum than as a standard 

 measure. I therefore tried an extension of it to 3 ft. 6 in., also 

 at 8 yards distance ; but then the other end of the beam began to 

 rise, and I found the cost augment, according to the accelerated 

 ratio of a district of high wages, beyond the proper limit. I now 

 therefore increased the distance to 10, and occasionally even to 12 

 yards, without perceiving much difference in the result ; though 

 on the whole, perhaps, it was less generally satisfactory than in the 

 former case. Early in these operations 1 resolved to treat ex- 

 perimentally a field of about four acres in my own occupation, 

 and to ascertain whether it would distinctly answer the plain but 

 doubtful question which I wished to solve, if fairly put to it. 

 I accordingly divided it into two halves, and drained one side at a 

 depth of 3 feet, with intervals of 10 yards ; the other to 4 feet 

 deep, with 13 yards of distance ; giving to each half a separate 

 outlet. The field is one of a poor description originally, lying 

 on a steep S.W. slope, which in this country implies across the 

 edge of the geological beds; for the most part boasting but a 

 limited amount of soil, covering a stiff yellow clay ; but somewhat 

 more generous at its upper edge, which was also its steepest part, 

 and into which we thought it best to drive the drains still deeper 



