On T) raining. 



43 



at their extremities, — to about five or six feet, — in order to reach 

 well the outbreak of under-water which we believed it to contain. 

 This field I watched with mucTi interest. It was drained in the 

 first month of 1848. It has had the advantage of being well 

 broken up (especially the deeper half) for crops of roots ; and 

 yet I am obliged to confess that I never could satisfy myself as 

 to any clear evidence of advantage on one side over the other ; and 

 at the present moment, near 3J years since the work was 

 done, there are parts stretching over hoth the halves, of which 

 the surface is undried, and that apparently with little reference 

 to the vicinity of the drains ; though the outlets have never failed 

 to do their duty. 



These last facts however, by no means unexampled in my 

 experience here, and of w^hich I have several other instances, seem 

 to me to prove two things irresistibly; first, that to clear such 

 ground of bottom icater deep drains are indispensable, and, within 

 rational limits, the deeper the better ; and, secondly, that in soils 

 so circumstanced the surface and the bottom drainage are two dis- 

 tinct things, with a real difference ; of which, though the latter 

 be complete and effective, the former may be at the same time a 

 failure. Looking then, primarily, to the fundamental and per- 

 manent source of saturation in such land from beneath, my con- 

 viction has been only thereby strengthened, that it can be reached 

 by deep drains alone ; I accordingly adopted a depth of 4 feet 

 in various localities. But then again, immediately sprung up 

 the difficulty of the cost, depending inversely on the distances, 

 which, when these were not proportionally expanded, became 

 seriously heavy. To meet this I determined to try an interval 

 between the 4-feet drains, in the first instance so much orpeater 

 that it might be possible to interpolate others if a failure should 

 require it. I placed them therefi^re at 16 or 18 yards apart, and 

 I was the less doubtful of this course, because in some of these 

 cases the subsoil seemed of a somewhat less tenacious character, 

 owing to a certain silicious admixture in its substance. But I 

 must avow that the experiment has not completely answered, and 

 that still verdant rushes, with a spongy or pasty surface, proclaim 

 that we have been partially baffled. It should be observed, 

 however, in passing, that much of this land lies high and exposed, 

 and where the temperature from various causes must needs be 

 generally low. 



These imperfect and unsatisfactory results seemed to tell me 

 in clear language that the problem was still unsolved, and to bid 

 me re-examine and carefully consider its elements before I could 

 hope to meet its peculiar difficulties. The result to be, if possible, 

 attained was, to devise a system which without, on the one hand, 

 sacrificing what I believe to be the essential condition of depth, 

 or, on the other, unduly exceeding that of cost^ might be better 



