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small weight without breaking, although it yields one another, which go so deep as to reach the very much, it is in these circumstances called a gravel; for, as the water there meets with no swaggle. But, whatever be the nature of the resistance, it readily flows out at these openings, bog, it is invariably occasioned by water being and is carried off by the drain without being forced forced up through a bed of clay, as just now de- up through the earth; so that the ground is left scribed, and dissolving or softening, if you will, entirely dry ever after. I have likewise drained a part thereof: I say only a part; because several fields in this way; and, as I have generally whatever may be the depth of the bog or found the appearance pretty much alike, I shall, swaggle, it generally has a partition of solid for the information of the inexperienced reader, clay between it and the reservoir of water under give a short account of them. If you attempt to it, from whence it originally proceeds: for if this make your pit in one of these soft quaggy places were not the case, and the quantity of water were where the water is found in great abundance, you considerable, it would meet with no sufficient re- will meet with very great difficulty in forming it; sistance from the bog, and would issue through for, as the substance of which it is composed is soft, it with violence, and carry the whole semi-fluid it will always flow into the hole as fast as you dig mass along with it. But this would more inevi- it; on which account I would advise, not to attably be the case if there was a crust at the tempt to make the pit in the swaggle, but as bottom of the bog, and if that crust should ever near it in the solid earth as you 'conveniently can. be broken, especially if the quantity of water However, it it is pretty firm, and of no great exunder it were very considerable: and as it is tent, it is sometimes practicable to make a pit in probable, that in many cases of this sort, the the soft bog at the driest time of the year. This I water slowly dissolves more and more of this have sometimes practised, which gave me an opunder crust, I make no doubt, but that in the portunity of observing the nature of these bogs revolution of many ages a great many eruptions more perfectly than I otherwise should have had. of this kind may have happened, though not In the trials of this kind that I have made, this deemed of sufficient importance to have the his- soft quaggy ground has seldom been above three tory of them transmitted to posterity. Of this or four feet deep, below which I have always kind, although formed of a different substance, I found a stratum of hard tough clay usually mixed consider the flow of the Solway moss, in Nor- with stone ; and so firm, that nothing but a matthumberland, to have been; which, upon the lock or pick-axe could penetrate it; and, as this 16th of November, 1771, burst its former boun- is comparatively so much drier than the ground daries, and poured forth a prodigious stream of above it, an inexperienced operator is very apt semi-Auid matter, which in a short time covered to imagine that this is the bottom that he is in several hundred acres of very fine arable ground. search of. In digging through this stratum you Nor will any one, who is acquainted with the will frequently meet with small springs oozing nature of moss, who knows its resemblance to out in all directions; some of them that might clay, in its quality of absorbing and retaining fill the tube of a small quill, and others so small water, and its very easy diffusibility therein, be as to be scarcely perceptible; but, without resurprised at this; as, from all these properties, it garding these, you must continue to dig on, withis much better adapted for forming an extensive out intermission, till you come to the main body bog, and therefore in greater danger of producing of the reservoir, if I may so call it, that is conan extensive devastation by an eruption of the tained in the rock, gravel, or sand; which you water into it, than those that are formed of any will generally find from two to four feet below kind of clay whatever. If the bog or swampy the bottom of the swaggle, and which you will ground is upon a declivity, the ditch ought to be be in no danger of mistaking when you come to it: carried across the field about the place where for, if there has been no opening made before that the lowest springs arise. But if the surface of in the field, as soon as you break the crust imthe ground is level, or nearly so, as between A mediately above the gravel or rock, the water and B, fig. 4, and the springs break out in seve bursts forth like a torrent; and, on some occaral places, 99999, so as to form soft quagmires, sions, rises like a jet d'eau to a considerable height interspersed through the whole of the field, it above the bottom of the ditch; and continues to will be of little consequence in what part the flow off with great impetuosity for some time, drain is opened; for if it be dug up so deep as to till the pent up water being drained off, the allow the water to rise in it with freedom, it will violent boiling up begins to subside, and the issue through that opening, and the field will be strength of the current to abate; and, in a short left perfectly dry. But as it may frequently time, it flows gently out like any ordinary spring; happen that the stratum of gravel should be at a -allowing it to remain in this state, the quaggy considerable depth beneath the surface of the earth begins to subside, and gradually becomes earth, and as it may be sometimes even below firmer and firmer every day; so that, in the space the level of the place into which the drain must of a few months, those bogs whieh were formerly be emptied, it might sometimes be extremely so soft as hardly to support the weight of a small difficult to make a ditch so deep as to reach dog, become so firm, that oxen and horses may the bed of sand or gravel. But it is lucky tread upon them without any danger of sinking, for us that this is not absolutely necessary in at the very wettest season of the year. I have the present case; as a drain of two or three had a field of this nature, that, by having only feet deep, as at D, will be equally effectual one such pit as I have now described opened in with one that should go to the gravel
. All that is it, was entirely drained to the distance of above necessary in this case, is to sink pits P in the 100 yards around it in every direction. But as course of the drain, at a moderate distance from it is possible that the stratum in which the water
runs may be in some places interrupted, it will but when the dry weather of summer sets in, the de in general expedient to make several of these moisture is diminished, and the surface becomes its, if the field is of great extent; always car- hard; and it is rent into many large gaps which ying the drain forward through the lowermost allow free admission to the sun and air, so as to jart of the field, or as near the quag as you con- scorch up almost every plant that is sowed upon ieniently can; and sinking a pit wherever you it; and, as these soils are usually in themselves may judge it will be most necessary. But, if the naturally fertile when drained, it were to be stratum of gravel is not interrupted, there will be wished that some method could be discovered, no violent burst of water at opening any of these that would be less expensive than what is usually after the first, as I have frequently experienced. practised with regard to some soils of this kind To keep these wells from closing up after they in Essex; where they make covered drains of two are made, it is always expedient to fill them up feet and a half deep, running diagonally through with small stones immediately after they are the whole field, at the distance of twenty feet made, which ought to rise to the height of the from each other.' bottom of the drain. I have often imagined, In the Georgical Essays, T. B. Bayley, Esq. that the expense of digging these pits might be of Hope, near Manchester, gives the following saved by boring a hole through this solid stratum directions for making covered drains: First of clay with a large wimble made on purpose; make the main drains down the slope or fall of but, as I never experienced this, I cannot say the field. When the land is very wet, or has not whether or not it would answer the desired end much fall, there should, in general, be two of exactly. If the whole field that is to be drained these to a statute acre; for the shorter the narrow consists of one extensive bog, it will require a drains are, the less liable they will be to accilong time before the whole work can be entirely dents. The width of the trench for the main finished, as it will be impossible to open a drain drains should be thirty inches at top, but the through it till one part of it is first drained, and width at the bottom must be regulated by the becomes solid ground. In a situation of this nature and size of the materials intended to be kind, the undertaker, after having opened a drain used. If the drain is to be made of bricks ten to convey the water from the lowest part of the inches long, thiee inches thick, and four inches bog, must approach as near to the swampy ground in breadth, then the bottom of the drain must as he can, and there make his first pit; which be twelve inches; but if the common sale will drain off the water from the nearest parts of bricks are used, then the bottom must be proporthe bog. When this has continued open for some tionably contracted. In both cases there must time, and that part of the boy has become so be an interstice of one inch between the bottom solid as to admit of being worked, let him con- brick and the sides of the trench, and the vacuity tinue the ditch as far forward through it as the must be filled up with straw, rushes, or loose situation it is in will admit of, and there sink mould. For the purpose of making these drains, another pit, and proceed gradually forward in the I order my bricks to be moulded ten inches long, same manner; making cross cuts where necessary, four broad, and three thick, which dimensions till the whole be finished. In this manner, may always make the best drains. The method I any bog or track of spouting ground of this na- pursue in constructing my main drains is as folture, be rendered dry at a very inconsiderable lows: when the ground is soft and spongy, the expense; and, as there can be no other method bottom of the drain is laid with bricks placed of draining ground of this sort effectually, I re across, On these, on each side, two bricks are commend the study of it to the attention of every laid flat, one upon the other, forming a drain six diligent farmer who may have occasion for it. inches high and four broad, which is covered Let him first be extremely cautious in examining with bricks laid fat. When the bottom of the all the circumstances of his particular fields, that trench is found to be a tirm and solid body, as he may be certain which of the classes above clay, or marle, the bottom of the drain does not enumerated it may be ranked with; and, when then require being laid with bricks. In that case, be is perfectly sure of that, he may proceed with- the sides are formed by placing one brick edgeout fear, being morally certain of siccess. There ways, instead of two laid fat. This latter method is, however, one kind of damp ground not yet is much cheaper, and in such land equally durparticularly specified, that I have purposely able with the other. When stones are used inomitted taking notice of till this time, as I have stead of bricks, the bottom of the drain should never had any opportunity of examining parti- be about eight inches in width. And here it will: cularly into the nature of it, nor of ascertaining, be proper to remark, that, in all cases, the botby experience, what is the most proper method tom of the main drains must be sunk four inches of treating it. The soil I have now particularly below the level of the narrow ones, even at the in my eye, consists of a deep strong clay that point where the latter fall into them. The main does not vary its nature even on the surface, but drains should be kept open till the narrow ones in as far as manures may have rendered it more are begun from them, after which they may be friable and tender; the color usually inclines to finished; but before the earth is returned upon a reddish cast, and, for the most part, it is situated the stones or bricks, it will be advisable to upon the side of some declivity. This bed of throw in straw, rushes, or brush-wood, to increase clay reaches to a great depth, without any varia, the freedom of the drain. The small narrow tion, and is intermixed with a considerable quan- drains should be cut at the distance of sixteen tity of small round stones. Many soils, of the or eighteen feet from each other, and should fall sort now described, are apt to be continually into the main drain at very acute angles, to preinoist and full of water during the winter season; vent any stoppage. At the point where they fall
in, and eight or ten inches above it, they should of direction, and marked out the trench, to begin be made firm with brick or stone. These drains at the bottom or lowest level, carrying the trench should be eighteen inches wide at top, and six- gradually up. The fall of the water need not be teen at bottom.'See plate Dogs and Drains. Fig. above a few inches in 100 yards. The auger, 3, represents a field with drains, laid out accord- which must often be used for tapping, need not ing to Mr. Bayley's method. The black lines exceed two inches in diameter. Mr. Elkington represent the main drains, and the dotted lines bored a hole with one, to the depth of thirty represent the narrow drains communicating with feet, which threw up water equal to three hogsthe former from all parts of the field.
heads in a minute, and completely drained all About the same time that Dr. Anderson had the neighbourhood. In such cases, farther opereduced the system of draining to scientific prin- rations in draining are unnecessary. In other ciples in Scotland, Mr. Joseph Elkington, of cases, the trench being once made, and the spring Princethorpe, in Warwickshire, appears to have cut off, by tapping, or otherwise, it remains only made some similar discoveries in England. The to determine, whether it is to be kept open or priority, indeed, is claimed by Dr. Anderson, covered. If the drain can be made a fence, he but as each party has his merits, and as the public prefers leaving it open; if not, to cover it. His is, doubtless, highly indebted to both, we shall mode is, to make it square, either of brick or fiat not presume to decide upon this point. The stones. A trench made of a particular kind of great object of Mr. Elkington's system is the bricks, invented by Mr. Elkington, may last for draining of lands rendered wet by waters con- fifty, or even 100 years. Mr. Elkington prüfined beneath the surface, and attempting to rise poses a farther improvement of this discovery, in the manner of springs. Among these, bogs by applying the treasures of water thus obtained or morasses are the chief. Having attempted, a to the purpose of flooding dry grounds, as well considerable number of years ago, to drain a as to the turning of mills, and to other engines piece of ground of this kind on his farm at used in manufactures. Princethorpe, hy making a trench of five feet On the drainage of mired and varied soils of deep, but without success, he thought it might the clayey kind, we have the following useful be of use to know, what kind of strata lay under observations in Mr. Loudon's Encyclopedia of the trench. Accordingly, he forced an iron crow, Agriculture :- The business of draining is here,' of about an inch and a half in diameter, three feet he remarks, 'considerably inore tedious and difdown, and upon taking it out, was agreeably sur- ficult than where the superficial and internal prised, to find a great quantity of water burst forth, parts have greater regularity. In sueh sorts of and run down the trench. This led him to think lands, as all the different collections of water are of applying an auger, an instrument fitter for the perfectly distinct from each other, by means o. purpose of boring, which, upon trial, he found the beds of clay that separate them, each collecequalled his expectations; and, by continuing tion becomes so much increased, or accumulated, the same plan with the auger, he at last drained in the time of heavy rains, that they are filled all the wet parts of his farm, which were nume- quite to the level of the surface of the clay by rous, and had proved destructive to his sheep, which they are surrounded; when the water by inducing the rot. When a morass is to be getting a free passage, as it would over the edges drained, his first object is to ascertain the direc- of a bowl or dish, overflows and saturates the tion in which the trench is to be dug. The sub- surface of that bed of clay in such a manner, as stance of his rules for this, as laid before the to render it so perfectly wet and sour, that its Board of Agriculture in 1796, are these : 1. To produce becomes not only annually more and obtain as much knowledge as possible respecting more scanty, but the soil itself more sterile and the strata in the neighbourhood. . 2. To direct unproductive. From the sand-beds, in such the trench so as to hit the bottom of the bed, cases, having no communication with each other, which occasions the mischief, and the particular it must evidently require as many drains as there spot where the main spring lies. 3. If there are are beds of this kind, in order fully to draw of various beds through which the water issues, to the water from each of them. A drain or trench prefer the stone ur.e for draining the whole; and is therefore recommended to be cut from the to make the trench from six to eight yards from nearest and lowest part of the field intended to the tail of the bed, where the rock ends, because be drained, up to the highest and most distant in limestone, and other rocks, the tail, as it is sand-bank in such a line of direction as, if postechnically termed, is harder than any other partsible, to pass through some of the intermediate of the rock; but a few yards above it, it is softer, sand-beds, and prevent the labor and expense of and the water is more accessible. The tail of making longer cuts on the sides, which would these beds may often be found jutting out in a otherwise be requisite. point. 4. To direct the trench in a line with the Where the different beds of sand and clay are bottom of the hill; as it makes the best separa- of less extent, and lie together with greater retion between the upland and meadow enclosures, gularity, they can be drained in a more easy where the spring can be best intercepted. The manner with less cuiting, and of course at less trench, however, must be carried in or near the expense. Below the layers or beds of sand and line of the spring; for, if it diverges to any dis- clay that lie, in this manner, alternately together, tance, all chance of reaching the spring by tap- and nearly parallel to each other, is generally a ping is over, and the labor of digging it probably body of impervious clay, which keeps up the lost. 5. To make a new trench, rather than to water that is contained in the sand, and which, to tap the spring in any old brook, or run of being constantly full, renders the adjacent clay water. 6, and lastly, having fixed on the line moist; and in wet seasons runs or trickles over
it. As, in these cases, the principal under-stra- bottomed. In order to remove this kind of wettum of clay is rarely above four or five feet be- ness, it seldom requires more than a few drains, low the surface, a drain is advised to be cut to made according to the situation and extent of that depth through the middle of the field, if it the field, of such a depth as to pass a few inches have a descent from both sides; but if it decline into the clay, between which, and the under surall to one side, the drain must be made in that face of the porous earth above, there will obplace, as the water will more readily discharge viously be the greatest stagnation, and conseitself into it; and unless the field be of great quently, collection of water, especially where it extent, and have more depressions or hollows in does not become much visible on the surface. In it than one, one drain may be quite sufficient for these cases there is not any necessity for having the purpose, as, by crossing the different beds that recourse to the use of the boring instrument, as retain the water, it must take it off from each of there is no water to be discharged from below. them. A principal difficulty in draining ground When the field to be drained has only a slight of this nature, and which renders it impractica- declination, or slope, from the sides towards the ble by one drain, is when the direction of the middle, one drain cut through the porous superalternate layers, or beds of clay and sand, lieficial materials into the clay, in the lowest part across the declivity of the land, so that one drain of the ground, may be sufficient to bring off the can be of no other service than that of convey. whole of the water detained in the porous soil. ing away the water after it has passed over the This effect may likewise be greatly promoted, by different strata, and would naturally stagnate in laying out and forming the ridges so as to acthe lowest part of the field, if there was no other cord with the direction of the land, and by the passage for it. Where the land lies in this way, use of the plough or spade in removing obstrucwhich is frequently the case, it will therefore be tions, and deepening the furrows. In such situanecessary, besides the drain in the lowest part, tions, where the drain has been formed in this to have others cut up from it in a slanting di- manner, the water will flow into it through the rection across the declivity, which by crossing porous surface materials, as well as if a number of all the different veins, or narrow strata of sand, small trenches were cut from it to each side, as is may be capable of drawing the water from each the practice in Essex and some other parts of the of them. In forming the drains in these cases, country; but which is often an unnecessary labor it is recommended that, after laying the bottom and expense. The drain made in the hollow in the manner of a sough, or in the way of a may frequently serve as a division of the field, triangle, it be filled some way up by small stones, in which case it may be open; but in other cir. tough sods being applied, the green side down- cumstances it may be more proper to have it wards, upon them before the mould is filled in. covered. Where a field of this description has But, where stones cannot be readily procured, more than one hollow in its surface, it will obfaggots may be employed in their place, where viously be requisite to have more than one main they are plentiful : the under part of the drain drain; but when it is nearly level, or only inbeing laid, or coupled, with stones, so as to form clines slightly to one side, a trench or drain a chaunel or passage for the conveyance of the along the lowest part, and the ridges and furwater that may sink through the faggots, and for rows formed accordingly, may be sufficient for the purpose of rendering them more durable; effecting its drainage. There may, however, be as where the water cannot get freely off, which cases, as where a field is large and very flat, in is generally the case where there is not an open which some side-cuts from the principal drain passage made of some solid material, it must, by may be necessary, which must be made a little its stagnation, soon destroy the faggots, and into the clay, and as narrow as they can be choke up the drain.
wrought, and then filled up with stones or other · The mode of draining retentite soils, is ma- suitable materials.' terially different from that which has been de • What is called the Esser method of draining scribed above. Many tracts of level land are in ploughed springy lands, where the surface soil injured by the stagnation of a superabundant is tenacious, is described by Kent, and consists quantity of water in the upper parts of the sur- in substituting small under-drains for open furface materials, which does not rise up into them rows; or in some cases having a small unler. from any reservoirs or springs below. The re- drain beneath every other or every third furrow, moval of the wetness in these cases may, for the These drains lead to side or fence ditches, where most part, be effected without any very heavy they discharge themselves.' For draining of expense. From the upper or surface soil, in mines, see MINING. such cases, being constituted of a loose porous Drains may be conveniently classed, as Mr. stratum of materials, to the depth of from two to Loudon observes, under, 1. Drains of conveyfour or five feet, which has a stiff retentive body ance simply; and 2. Drains of conveyance and of clay underneath it, any water that may come collection. The most complete drain of conveyupon the surface from heavy rains, or other ance is a large pipe of metal, masonry, or brickcauses, readily filtrates and sinks down through work: and the most complete collecting drain, it, until it reaches the obstructing body of clay one formed with a channel built on the sides, which prevents it from proceeding; the conse- and covered with flat-stones, with a superstraquence of which is, that the porous open soil tum of round stones or splinters, dimivishing to above is so filled and saturated with water, as to the size of gravel as they rise to the surface, and be of little utility for the purpose of producing there covered with the common soil. As the crops of either grain or grass. Land situated in best constructions, however, are not always practhis way, is frequently said by farmers to be wet- ticable, the following are a few leading sorts
adapted for different situations. (We are in- spray, straw, or rushes, and finally the surface debted to Mr. Loudon for this selection). soil.
For drains of conveyance, there are the walled The spray drain is generally like the gravel or box drain, the barrel drain, the walled or the drain, of small size, and formed like it, with an triangular drain, and the arched drain, fig. 1. acute angled bottom. In general, tne spray is trod
firmly in; though in some cases it is previously Fig. 2.
formed into a cable, as in the brush-wood drain. Drains of this sort are much in use in grass lands, and when the spray of larch-wood, heath, or ling can be got, they are of great durability. The straw drain, when reeds, rushes, and bean straw is used, is sometimes made like the spray drain, by pressing the loose material down, or forming a cable; but in general the straw is twisted into ropes as big as a mau's leg, by the aid of a machine, and three or more of these laid in the bottom of a triangular drain, with or
without the protection of three turves. Drains of collection are formed of stone, brick,
The turf drain, gravel, cinders, wood, spray, straw, turf, and fig. 3, may be
Pig. 3. earth alone.
made of any conThe boxed and rubble drain, fig. 2, is a drain venient depth, of conveyance and collection. The common but it must be at rubble drain is formed of rough land-stones of least the breadth any sort, not exceeding six or seven inches in of a turf at botdiameter, thrown in the bottom, with smaller tom. The drain ones over, and, if to be had, gravel or ashes at being dug out top. On this is laid a thin layer of straw or as if it were to haum of any kind, and the remainder is filled be filled with up with the surface soil.
stones or any orThe brick drain is formed in a great variety of dinary material; ways, either from common bricks and bats in the operator next, with a spade three inches imitation of the boxed and rubble, or rubble wide, digs a narrow channel along its centre a, drain; or by the use of bricks made on pur- clearing it out with the draining scoop; and pose, of which there are great variety. Drain- over this the turves, b, are laid without any ing tiles to be used with effect as collecting other preparation, or any thing put over them drains, should always be covered a foot in depth, but the earth that was excavated. This is or more, with stones or gravel.
found to be a very cheap, and, considering the The gravel or cinder drain is seldom made materials, a surprisingly durable method of draindeep, though, if the materials be large, they may ing; answering, in pasture-fields especially, all be made of any size. In general they are used the purposes that the farmer can expect to derive in grass lands; the section of the drain being from drains constructed with more labor, and at an acute-angled triangle, and the materials being a much greater expense. They are said to las! filled in, the smallest uppermost, nearly to the frequently twenty years and upwards; but the ground's surface.
period which it can be supposed they will conThe wood drain is of various kinds. A very tinue to prove effectual, must depend on the sufficient and durable construction consists of nature of the soil, and the current of water. poles or young fir-trees stripped of their branches The triangular sod drain is thus made: when and laid in the bottom of the drain lengthways. the line of drain is marked out, a sod is cut in They are then covered with the branches and the form of a wedge, the grass side being the spray. Another form is that of filling the drain narrowest, and the sods being from twelve to with faggot-wood, with some straw over. A eighteen inches in length. The drain is then variety of this mode is formed by first setting in cut to the depth required, but is contracted to a cross stakes to prevent the faggots from sinking; very narrow bottom. The sods are then set in but they are of 'no great use, and often occasion with the grass side downwards, and pressed as such drains to fail sooner than common faggot far as they will go. As the figure of the drain drains, by the greater vacuity they leave after does not suffer them to go to the bottom, a ca. the wood is rotten. In some varieties of this vity is left, which serves as a watercourse; and drain the brush-wood is first laid down alongside the space above is filled with the earth thrown out. the drain, and formed by willow, or other ties, The hollow furrow drain is only used in sheepinto an endless cable of ten or twelve inches in pastures. Wherever the water is apt to stagdiameter, and then rolled in, which is said to nate, deep furrow is turned up with a stout torm an excellent drain with the least quantity of plough. After this, a man with a spade pares off materials, and to last a longer time than any of the loose soil from the inverted sod, and scatters the modes above mentioned. Some cut the it over the field, or casts it into hollow places. brush-wood into lengths of three or four feet, The sod thus pared, and brought to the thickand place them in a sloping direction with thé ness of about three inches, is restored to its oriroot end of the branch in the bottom of the ginal situation, with the grassy side uppermost, drain ; others throw in the branches at random, as if no furrow had been made. A pipe or openwith little preparation, and cover them with ing is thus formed beneath it, two or three in