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Lord Berners having adopted a method of drainage on his estate at Keythorpe, differing somewhat from any of the regular and more uniform modes which have been considered, a sharp controversy as to its merits has arisen, and still continues in England, which, like most controversies, may be of more advantage to others than to the parties immediately concerned.

The theory of the Keythorpe system seems to have been invented by Mr. Joshua Trimmer, a distinguished geologist of England, who, about 1854, produced a paper, which was published in the journal of the Royal Agricultural Society, on the "Keythorpe System." He states that his own theory was based entirely on his knowledge of the geological structure of the earth, which will be presently given in his own language, and that he afterwards ascertained that Lord Berners, who had no special theory to vindicate, had, by the "tentative process," or in plain English, by trying experiments, hit upon substantially the same system, and found it to work admirably.

Most people in the United States have no idea of what it is to be patronized by a lord. In England, it is thought by many to be the thing needful to the chance, even, of success of any new theory, and accordingly, Mr. Trimmer, without hesitation, availed himself of the privilege of being patronized by Lord Berners; and the latter, before he was aware of how much the agricultural world was indebted to him for his valuable discoveries, suddenly found himself at the head of the "Keythorpe System of Drainage."

His lordship was probably as much surprised to ascertain that he had been working out a new system, as some man of whom we have heard, was, to learn that he had been speaking prose all his life! At the call of the public, however, his lordship at once gave to the world the facts in his possession, making no claim to any great discovery, and leaving Mr. Trimmer to defend the new system as best he might. The latter, in one of his pamphlets published in defence of the Keythorpe system, states its claims as follows:

"The peculiarities of the Keythorpe system of draining consist in this—that the parallel drains are not equidistant, and that they cross the line of the greatest descent. The usual depth is three and a half feet, but some are as deep as five and six feet. The depth and width of interval are determined by digging trial-holes, in order to ascertain not only the depth at which the bottom water is reached, but the height to which the water rises in the holes, and the distance at which a drain will lay the hole dry. In sinking these holes, clay-banks are found with hollows or furrows between them, which are filled with a more porous soil, as represented in the annexed sectional diagram.

Fig. 4.

 a a Trial-holes.

 b Clay-banks of lias or of boulder-clay.

 c A more porous warp-drift filling furrows between the clay-banks.

"The next object is to connect these furrows by drains laid across them. The result is, that as the furrows and ridges here run along the fall of the ground, which I have observed to be the case generally elsewhere, the sub-mains follow the fall, and the parallel drains cross it obliquely.

"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.

The discussion of the claims of that system—if such it may be called—may be valuable in America, where novelty is sure to attract, by showing that one more form of error has already been tried and "found wanting;" and so save us the trouble of proving its inutility by experiment.