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. THE WHARNCLIFFE SYSTEM. Lord Wharncliffe, with a view to effect adequate drainage at less expense than is usual in thorough drainage, has adopted upon his estate a sort of compromise system, which he has brought to the notice of the public in the Journal of the Royal Agricultural Society.