the conduit. Such soils are generally very firm. A narrow slab or inch board, fitting the bottom of the drain, will be a secure foundation for stone, a foot in depth, laid in the form which its nature may suggest. We will answer for the board. In taking up considerable lengths of drains 5 and 6 feet deep, and so laid more than sixty years ago, we have seen no instance in which either oak, alder, birch, or willow has been materially decayed; twigs and sticks, from similar depths, have been equally sound and tough. In the comparatively rare cases to which we have referred, we permit, without approval, the use of a stone conduit. We know no instance in which it is worth while (as Smith recommends) to quarry and break stones to form a conduit. We shall shock some and surprise many of our readers when we state confidently that in average soils, and, still more, in those which are inclined to be tender, horseshoe tiles form the weakest and most failing conduit which has ever been used for a deep drain. It is so, however, and a little thought, even if we had no experience, will tell us that it must be so. A doggerel song, quite destitute of humour, informs us that tiles of this sort were used in 1760 at Grandesburg Hall, in Suffolk, by Mr. Charles Lawrence, the owner of the estate. The earliest of which we had experience were of large area and of weak form. Constant failures resulted from their use, and the cause was investigated; many of the tiles were found to be choked up with clay, and many to be broken longitudinally through the crown. For the first evil two remedies were adopted; a sole of slate, of wood, or of its own material, was sometimes placed under the tile, but the more usual practice was to form them with club-feet. To meet the case of longitudinal fracture, the tiles were reduced in size, and very much thickened in proportion to their area. The first of these remedies was founded on an entirely mistaken, and the second on no conception at all of the cause of the evil to which they were respectively applied. The idea was, that this tile, standing on narrow feet, and pressed by the weight of the refilled soil, sank into the floor of the drain; whereas, in fact, the floor of the drain rose into the tile. Any one at all conversant with collieries is aware that when a strait work (which is a small subterranean tunnel 6 feet high and 4 feet wide or thereabouts) is driven in coal, the rising of the floor is a more usual and far more inconvenient occurrence than the falling of the roof: the weight of the two sides squeezes up the floor. We have seen it formed into a very decided arch without fracture. Exactly a similar operation takes place in the drain. No one had till recently dreamed of forming a tile drain, the bottom of which a man was not to approach personally within 20 inches or 2 feet. To no one had it then occurred that width at the bottom of the drain was a great evil. For the convenience of the operator the drain was formed with nearly perpendicular sides, of a width in which he could stand and work conveniently, shovel the bottom level with his ordinary spade, and lay the tiles by his hand; the result was a drain with nearly perpendicular sides and a wide bottom. No sort of clay, particularly when softened by water standing on it or running over it, could fail to rise under such circumstances; and the deeper the drain the greater the pressure, and the more certain the rising. A horseshoe tile, which may be a tolerably secure conduit in a drain of 2 feet, in one of 4 feet becomes an almost certain failure. As to the longitudinal fracture-not only is the tile subject to be broken by one of those slips which are so troublesome in deep draining, and to which the lightly-filled material, even when the drain is completed, offers an imperfect resistance, but the constant pressure together of the sides, even when it does not produce a fracture of the soil, catches hold of the feet of the tile, and breaks it through the crown. Consider the case of a drain formed in clay when dry, the conduit a horseshoe tile. When the clay expands with moisture, it necessarily presses on the tile, and breaks it through the crown, its weakest part. When the Regent's Park was first drained, large conduits were in fashion, and they were made circular by placing one horseshoe tile upon another. It would be difficult to invent a weaker conduit. On re-drainage, innumerable instances were found in which the upper tile was broken through the crown, and had dropped into the lower. Next came the form, tile and sole in one, and much reduced in size-a great advance; and when some skilful operator had laid this tile bottom upwards we were evidently on the eve of pipes. For the tile a round pipe moulded with a flat-bottomed solid sole O is now generally substituted, and is an improvement; but is not equal to pipes and collars, nor generally cheaper than they are. Almost forty years ago small pipes for land-drainage were used concurrently by the following parties, who still had no knowledge of each other's operations :-Sir T. Wichcote, of Asgarby, Lincolnshire (these we believe were socket-pipes)—Mr. R. Harvey, at Epping-Mr. Boulton, at Great Tew in Oxfordshire (these were porcelain 1inch pipes made by Wedgwood, at Etruria)—and Mr. John Read, at Horsemonden, in Kent. Most of these pipes were made with eyelet-holes to admit the water. Pipes for thorough-draining were incidentally mentioned in the Journal of the Agricultural Society, for May 1843, but they excited no general attention till they were exhibited by John Read (the inventor of the stomach-pump) at the Agricultural Show at Derby in that year. A medal was awarded to the exhibitor. Mr. Parkes was one of the Judges, and brought the pipes to the special notice of the Council, and was instructed by them to investigate their The tile has been said, by great authorities, to be broken by contraction, under some idea that the clay envelopes the tile and presses it when it contracts. That is nonsense. The contraction would liberate the tile. Drive a stake into wet clay; and when the clay is dry, observe whether it clips the stake tighter or has released it, and you will no longer have any doubt whether expansion or contraction breaks the tile. Shrink is a better word than contract. use and merits. From this moment inventions and improvements huddle in upon us faster than we can describe them. Collars to connect the pipes, a new form of drain, tools of new forms,-particularly one by which the pipe and collar are laid with wonderful rapidity and precision, by an operator who stands on the top of the drain-and pipe-and-collar-making machines (stimulated by repeated prizes offered by the Royal Agricultural Society), which furnish those articles on a scale of unexampled cheapness. For all these inventions and adaptations we are mainly indebted to Mr. Parkes. The economical result is, a drain 4 feet 6 inches deep, excavated and refilled at from 14d. to 2d. per yard-the workmen earning 12s. and upwards per week; and 333 yards of collared 14-inch pipes for 18s.-being 12s. per thousand for the pipes, and 68. per thousand for the collars; larger sizes at a proportionate advance. We shall best exemplify the improvements to our readers by describing the drain. It is wrought in the shape of a wedge, brought in the bottom to the narrowest limit which will admit the collar by tools admirably adapted to that purpose. The foot of the operator is never within 20 inches of the floor of the drain; his tools are made of iron plated on steel, and never lose their sharpness, even when worn to the stumps; because, as the softer material, the iron, wears away, the sharp steel edge is always promiThe sloping sides of the drain are self-sustaining, and the pressure on its floor is reduced to a minimum; the circular form of the pipe and collar enables them to sustain any pressure to which they can be subjected; the adaptation of the bed in which they lie to their size prevents their riggling. They form a continuous conduit, and whose continuity cannot be broken except by great violence. However steep the drain, the water running in the pipe can never wash up its floor. They offer almost insuperable impediments to the entrance of vermin, roots, or anything nent. • I am afraid that I must materially modify this expression as far as roots are concerned. The words "almost insuperable impediments" are except water, and they are more portable both to the field and in the field than any other conduit previously discovered cheap, light, handy, secure, efficacious. Perhaps some of our readers will boggle at this word efficacious. Doubts will begin to trouble inexperienced minds;-Will water get freely into these narrow-bottomed drains? Will pipes of this small capacity convey it away? The scepticism is natural; but on each point we are able to offer them abundant consolation and conviction-consolation from experience, conviction on argument. We have seen hundreds of drains wrought in the manner we have described and laid with pipes, and in no instance where the land contained water-of-drainage have they failed to run freely. We never heard any one say they did not. This ought to satisfy every person who is not of his own knowledge aware of an instance to the contrary: "Quod semper, not applicable. My own experience as to roots, in connexion with deep pipe draining, is as follows:-I have never known roots to obstruct a pipe through which there was not a perennial stream. The flow of water in summer and early autumn appears to furnish the attraction. I have never discovered that the roots of any esculent vegetable have obstructed a pipe. The trees which, by my own personal observation, I have found to be most dangerous, have been red willow, black Italian poplar, elder, ash, and broad-leaved elm. I have many alders in close contiguity with important drains, and, though I have never convicted one, I cannot doubt that they are dangerous. Oak, and black and white thorns, I have not detected, nor do I suspect them. The guilty trees have in every instance been young and free growing; I have never convicted an adult. These remarks apply solely to my own observation, and may of course be much extended by that of other agriculturists. I know an instance in which a perennial spring of very pure and (I believe) soft water is conveyed in socket pipes to a paper-mill. Every junction of two pipes is carefully fortified with cement. The only object of cover being protection from superficial injury and from frost, the pipes are laid not far below the sod. Year by year these pipes are stopped by roots. Trees are very capricious in this matter. I was told by the late Sir R. Peel that he sacrificed two young elm trees in the park at Drayton Manor to a drain which had been repeatedly stopped by roots. The stoppage was nevertheless repeated, and was then traced to an elm tree far more distant than those which had been sacrificed. Early in the autumn of 1850 I completed the drainage of the upper part of a boggy valley lying, with ramifications, at the foot of marly banks. The main drains converge to a common outlet, to which are |