Farm drainage / The Principles, Processes, and Effects of Draining Land with Stones, Wood, Plows, and Open Ditches, and Especially with Tiles

by Henry F. French

"The intervals between the parallel drains are irregular, varying, in the same field, from 14 to 21, 31, and 59 feet. The distances are determined by opening the diagonal drains at the greatest distance from the trial-holes at which experience has taught the practicability of its draining the hole. If it does not succeed in accomplishing the object, another drain is opened in the interval. It has been found, in many cases, that a drain crossing the clay-banks and furrows takes the water from holes lying lower down the hill; that is to say, it intercepts the water flowing to them through these subterranean channels. The parallel drains, however, are not invariably laid across the fall. The exceptions are on ground where the fall is very slight, in which case they are laid along the line of greatest descent. On such grounds there are few or no clay-banks and furrows."

It would seem highly probable that the mode of drainage adopted at Keythorpe, is indebted for its success at that place, to a geological formation not often met with. At a public discussion in England, Mr. T. Scott, a gentleman of large experience in draining, stated that "he never, in his practice, had met with such a geological formation as was said to exist at Keythorpe, except in such large areas as to admit of their being drained in the usual gridiron or parallel fashion."

It is claimed for this system by its advocates, that it is far cheaper than any other, because drains are only laid in the places where, by careful examination beforehand, by opening pits, they are found to be necessary; and that is a great saving of expense, when compared with the system of laying the drains at equal distances and depths over the field.

Against what is urged as the Keythorpe system, several allegations are brought.

In the first place, that it is in fact no system. Mr. Denton, having carefully examined the Keythorpe estate, and the published statements of its owner, asserts, that the drains there laid have no uniformity of depth—part of the tiles being laid but eighteen inches deep, and others four feet and more, in the same field.

Secondly, that there is no uniformity as to direction—part of the drains being laid across the fall, and part with the fall, in the same fields—with no obvious reason for the difference of direction.

Thirdly, that there is no uniformity as to materials—a part of the drains being wood, and a part tiles, in the same field.

Finally, it is contended that there is no saving of expense in the Keythorpe draining, over the ordinary mode, when all points are considered, because the pretended saving is made by the use of wood, where true economy would require tiles, and shallow drains are used where deeper ones would in the end be cheaper.

In speaking of this controversy, it is due to Lord Berners to say, that he expressly disclaims any invention or novelty in his operations at Keythorpe.

On the whole, although a work at the present day which should pass over, without consideration, the claims of the Keythorpe system, would be quite incomplete in its history of the subject, yet the facts elicited with regard to it are perhaps chiefly valuable, as tending to show the danger of basing a general principle upon an isolated case.