About the year 1846, when the first Act of the British Parliament authorizing "the advance of public money to promote the improvement of land by works of drainage" was passed, a careful investigation of the whole subject was made by a Committee of the House of Lords, and it was found that the best recorded opinions, if we except the peculiar views of Elkington, were represented by, if not merged into, those of Smith, of Deanston, which have already been stated, or those of Josiah Parkes. Mr. Parkes is the author of "Essays on the Philosophy and Art of Land Drainage," and of many valuable papers on the same subject, published in the journal of the Royal Agricultural Society, of which he was consulting engineer. He is spoken of by Mr. Denton as "one whose philosophical publications on the same subject gave a scientific bearing to it, quite irreconcilable with the more mechanical rules laid down by Mr. Smith." The characteristic views of Mr. Parkes, as set forth at that time, as compared with those of Mr. Smith, are-- "1st. _Less frequent drains_, at intervals varying from twenty-one to fifty feet, _with preference for wide intervals_. "2nd. _Deeper drains at a minimum depth of four feet_, designed with the two-fold object of not only freeing the active soil from stagnant and injurious water, but of converting the water falling on the surface into an agent for fertilizing; no drainage being deemed efficient that did not both remove the water failing on the surface, and 'keep down the subterranean water at a depth exceeding the power of capillary attraction to elevate it to near the surface.' "3rd. _Parallel arrangement of drains_, as advocated by Smith, of Deanston. "4th. _The advantage of increased depth_, as compensating for increased width between the drains. "5th. _Pipes of an inch bore, the 'best known conduit'_ for the parallel drains. (See Evidence before Lords' Committee on Entailed Estates, 1845, Q. 67.) "6th. _The cost of draining uniform clays should not exceed L3 per acre._" The most material differences between the views of these two leaders of what have been deemed rival systems of drainage, will be seen to be the following. Smith advocates drains of two to three feet in depth, at from ten to twenty-four feet distances; while Parkes contends for a depth of not less than four feet, with a width between of from twenty-one to fifty feet, the depth in some measure compensating for the increased distance. Mr. Parkes advocated the use of pipes of _one_ inch bore, which Mr. Smith contemptuously denominated "pencil-cases," and which subsequent experience has shown to be quite too small for prudent use.