There is, on the other hand, much land which only by thorough-draining can be rendered profitable for cultivation, or healthful for residence, and very much more, described as "ordinarily dry land," which draining would greatly improve in both productive value and salubrity.

The Surface Indications of the necessity for draining are various. Those of actual swamps need no description; those of land in cultivation are more or less evident at different seasons, and require more or less care in their examination, according to the circumstances under which they are manifested.

If a plowed field show, over a part or the whole of its surface, a constant appearance of dampness, indicating that, as fast as water is dried out from its upper parts, more is forced up from below, so that after a rain it is much longer than other lands in assuming the light color of dry earth, it unmistakably needs draining.

A pit, sunk to the depth of three or four feet in the earth, may collect water at its bottom, shortly after a rain;—this is a sure sign of the need of draining.

All tests of the condition of land as to water,—such as trial pits, etc.,—should be made, when practicable, during the wet spring weather, or at a time when the springs and brooks are running full. If there be much water in the soil, even at such times, it needs draining.

If the water of heavy rains stands for some time on the surface, or if water collects in the furrow while plowing, draining is necessary to bring the land to its full fertility.

Other indications may be observed in dry weather;—wide cracks in the soil are caused by the drying of clays, which, by previous soaking, have been pasted together; the curling of corn often indicates that in its early growth it has been prevented, by a wet subsoil, from sending down its roots below the reach of the sun's heat, where it would find, even in the dryest weather, sufficient moisture for a healthy growth; any severe effect of drought, except on poor sands and gravels, may be presumed to result from the same cause; and a certain wiryness of grass, together with a mossy or mouldy appearance of the ground, also indicate excessive moisture during some period of growth. The effects of drought are, of course, sometimes manifested on soils which do not require draining,—such as those poor gravels, which, from sheer poverty, do not enable plants to form vigorous and penetrating roots; but any soil of ordinary richness, which contains a fair amount of clay, will withstand even a severe drought, without great injury to its crop, if it is thoroughly drained, and is kept loose at its surface.

Poor crops are, when the cultivation of the soil is reasonably good, caused either by inherent poverty of the land, or by too great moisture during the season of early growth. Which of these causes has operated in a particular case may be easily known. Manure will correct the difficulty in the former case, but in the latter there is no real remedy short of such a system of drainage as will thoroughly relieve the soil of its surplus water.

The Sources of the Water in the soil are various. Either it falls directly upon the land as rain; rises into it from underlying springs; or reaches it through, or over, adjacent land.

The rain water belongs to the field on which it falls, and it would be an advantage if it could all be made to pass down through the first three or four feet of the soil, and be removed from below. Every drop of it is freighted with fertilizing matters washed out from the air, and in its descent through the ground, these are given up for the use of plants; and it performs other important work among the vegetable and mineral parts of the soil.

The spring water does not belong to the field,—not a drop of it,—and it ought not to be allowed to show itself within the reach of the roots of ordinary plants. It has fallen on other land, and, presumably, has there done its appointed work, and ought not to be allowed to convert our soil into a mere outlet passage for its removal.

The ooze water,—that which soaks out from adjoining land,—is subject to all the objections which hold against spring water, and should be rigidly excluded.

But the surface water which comes over the surface of higher ground in the vicinity, should be allowed every opportunity, which is consistent with good husbandry, to work its slow course over our soil,—not to run in such streams as will cut away the surface, nor in such quantities as to make the ground inconveniently wet, but to spread itself in beneficent irrigation, and to deposit the fertilizing matters which it contains, then to descend through a well-drained subsoil, to a free outlet.

From whatever source the water comes, it cannot remain stagnant in any soil without permanent injury to its fertility.

The Objection to too much Water in the Soil will be understood from the following explanation of the process of germination, (sprouting,) and growth. Other grave reasons why it is injurious will be treated in their proper order.

The first growth of the embryo plant, (in the seed,) is merely a change of form and position of the material which the seed itself contains. It requires none of the elements of the soil, and would, under the same conditions, take place as well in moist saw-dust as in the richest mold. The conditions required are, the exclusion of light; a certain degree of heat; and the presence of atmospheric air, and moisture. Any material which, without entirely excluding the air, will shade the seed from the light, yield the necessary amount of moisture, and allow the accumulation of the requisite heat, will favor the chemical changes which, under these circumstances, take place in the living seed. In proportion as the heat is reduced by the chilling effect of evaporation, and as atmospheric air is excluded, will the germination of the seed be retarded; and, in case of complete saturation for a long time, absolute decay will ensue, and the germ will die.

The accompanying illustrations, (Figures 1, 2 and 3,) from the "Minutes of Information" on Drainage, submitted by the General Board of Health to the British Parliament in 1852, represent the different conditions of the soil as to moisture, and the effect of these conditions on the germination of seeds. The figures are thus explained by Dr. Madden, from whose lecture they are taken:

As was stated in the previous chapter, the water which reaches the soil may be considered under two heads:

1st—That which reaches its surface, whether directly by rain, or by the surface flow of adjoining land.

2d—That which reaches it below the surface, by springs and by soakage from the lower portions of adjoining land.

The first of these is beneficial, because it contains fresh air, carbonic acid, ammonia, nitric acid, and heat, obtained from the atmosphere; and the flowage water contains, in addition, some of the finer or more soluble parts of the land over which it has passed. The second, is only so much dead water, which has already given up, to other soil, all that ours could absorb from it, and its effect is chilling and hurtful. This being the case, the only interest we can have in it, is to keep it down from the surface, and remove it as rapidly as possible.

The water of the first sort, on the other hand, should be arrested by every device within our reach. If the land is steep, the furrows in plowing should be run horizontally along the hill, to prevent the escape of the water over the surface, and to allow it to descend readily into the ground. Steep grass lands may have frequent, small, horizontal ditches for the same purpose. If the soil is at all heavy, it should not, when wet, be trampled by animals, lest it be puddled, and thus made less absorptive. If in cultivation, the surface should be kept loose and open, ready to receive all of the rain and irrigation water that reaches it.

In descending through the soil, this water, in summer, gives up heat which it received from the air and from the heated surface of the ground, and thus raises the temperature of the lower soil. The fertilizing matters which it has obtained from the air,—carbonic acid, ammonia and nitric acid,—are extracted from it, and held for the use of growing plants. Its fresh air, and the air which follows the descent of the water-table, carries oxygen to the organic and mineral parts of the soil, and hastens the rust and decay by which these are prepared for the uses of vegetation. The water itself supplies, by means of their power of absorption, the moisture which is needed by the particles of the soil; and, having performed its work, it goes down to the level of the water below, and, swelling the tide above the brink of the dam, sets the drains running, until it is all removed. In its descent through the ground, this water clears the passages through which it flows, leaving a better channel for the water of future rains, so that, in time, the heaviest clays, which will drain but imperfectly during the first one or two years, will pass water, to a depth of four or five feet, almost as readily as the lighter loams.

Now, imagine the drains to be closed up, leaving no outlet for the water, save at the surface. This amounts to a raising of the dam to that height, and additions to the water will bring the water-table even with the top of the soil. No provision being made for the removal of spring and soakage water, this causes serious inconvenience, and even the rain-fall, finding no room in the soil for its reception, can only lie upon, or flow over, the surface,—not yielding to the soil the fertilizing matters which it contains, but, on the contrary, washing away some of its finer and looser parts. The particles of the soil, instead of being furnished, by absorption, with a healthful amount of moisture, are made unduly wet; and the spaces between them, being filled with water, no air can enter, whereby the chemical processes by which the inert minerals, and the roots and manure, in the soil are prepared for the use of vegetation, are greatly retarded.

Instead of carrying the heat of the air, and of the surface of the ground, to the subsoil, the rain only adds so much to the amount of water to be evaporated, and increases, by so much, the chilling effect of evaporation.

On this subject Mr. Gisborne says: "If we should give a stimulus to amateur draining, we shall do a great deal of harm. We wish we could publish a list of the moneys which have been squandered in the last 40 years in amateur draining, either ineffectually or with very imperfect efficiency. Our own name would be inscribed in the list for a very respectable sum. Every thoughtless squire supposes that, with the aid of his ignorant bailiff, he can effect a perfect drainage of his estate; but there is a worse man behind the squire and the bailiff,—the draining conjuror. * * * * * * These fellows never go direct about their work. If they attack a spring, they try to circumvent it by some circuitous route. They never can learn that nature shows you the weakest point, and that you should assist her,—that hit him straight in the eye is as good a maxim in draining as in pugilism. * * * * * * If you wish to drain, we recommend you to take advice. We have disposed of the quack, but there is a faculty, not numerous but extending, and whose extension appears to us to be indispensable to the satisfactory progress of improvements by draining,—a faculty of draining engineers. If we wanted a profession for a lad who showed any congenial talent, we would bring him up to be a draining engineer." He then proceeds to speak of his own experience in the matter, and shows that, after more than thirty years of intelligent practice, he employed Mr. Josiah Parkes to lay out and superintend his work, and thus effected a saving, (after paying all professional charges,) of fully twelve per cent. on the cost of the draining, which was, at the same time, better executed than any that he had previously done.

It is probable that, in nearly all amateur draining, the unnecessary frequency of the lateral drains; the extravagant size of the pipes used; and the number of useless angles which result from an unskillful arrangement, would amount to an expense equal to ten times the cost of the proper superintendence, to say nothing of the imperfect manner in which the work is executed. A common impression seems to prevail, that if a 2-inch pipe is good, a 3-inch pipe must be better, and that, generally, if draining is worth doing at all, it is worth overdoing; while the great importance of having perfectly fitting connections is not readily perceived. The general result is, that most of the tile-draining in this country has been too expensive for economy, and too careless for lasting efficiency.

It is proposed to give, in this chapter, as complete a description of the preliminary engineering of draining as can be concentrated within a few pages, and a hope is entertained, that it will, at least, convey an idea of the importance of giving a full measure of thought and ingenuity to the maturing of the plan, before the execution of the work is commenced. "Farming upon paper" has never been held in high repute, but draining upon paper is less a subject for objection. With a good map of the farm, showing the comparative levels of outlet, hill, dale, and plain, and the sizes and boundaries of the different in closures, a profitable winter may be passed,—with pencil and rubber,—in deciding on a plan which will do the required work with the least possible length of drain, and which will require the least possible extra deep cutting; and in so arranging the main drains as to require the smallest possible amount of the larger and more costly pipes; or, if only a part of the farm is to be drained during the coming season, in so arranging the work that it will dovetail nicely with future operations. A mistake in actual work is costly, and, (being buried under the ground,) is not easily detected, while errors in drawing upon paper are always obvious, and are remedied without cost.

For the purpose of illustrating the various processes connected with the laying out of a system of drainage, the mode of operating on a field of ten acres will be detailed, in connection with a series of diagrams showing the progress of the work.

A Map of the Land is first made, from a careful survey. This should be plotted to a scale of 50 or 100 feet to the inch,

The maps in this book are, for convenience, drawn to a scale of 160 feet to the inch.

The next step is to locate the contour lines of the land, or the lines of equal elevation,—also called the horizontal lines,—which serve to show the shape of the surface. To do this, stake off the field into squares of 50 feet, by first running a base line through the center of the greatest length of the field, marking it with stakes at intervals of 50 feet, then stake other lines, also at intervals of 50 feet, perpendicular to the base line, and then note the position of the stakes on the maps; next, by the aid of an engineer's level and staff, ascertain the height, (above an imaginary plain below the lowest part of the field,) of the surface of the ground at each stake, and note this elevation at its proper point on the map. This gives a plot like Fig. 5. The best instrument with which to take these levels, is the ordinary telescope-level used by railroad engineers, shown in Fig. 6, which has a telescope with cross hairs intersecting each other in the center of the line of sight, and a "bubble" placed exactly parallel to this line. The instrument, fixed on a tripod, and so adjusted that it will turn to any point of the compass without disturbing the position of the bubble, will, (as will its "line of sight,") revolve in a perfectly horizontal plane. It is so placed as to command a view of a considerable stretch of the field, and its height above the imaginary plane is measured, an attendant places next to one of the stakes a levelling rod, (Fig. 7,) which is divided into feet and fractions of a foot, and is furnished with a movable target, so painted that its center point may be plainly seen. The attendant raises and lowers the target, until it comes exactly in the line of sight; its height on the rod denotes the height of the instrument above the level of the ground at that stake, and, as the height of the instrument above the imaginary plane has been reached, by subtracting one elevation from the other, the operator determines the height of the ground at that stake above the imaginary plane,—which is called the "datum line."

The next operation is to trace, on the plan, lines following the same level, wherever the land is of the proper height for its surface to meet them. For the purpose of illustrating this operation, lines at intervals of elevation of one foot are traced on the plan in Fig. 8. And these lines show, with sufficient accuracy for practical purposes, the elevation and rate of inclination of all parts of the field,—where it is level or nearly so, where its rise is rapid, and where slight. As the land rises one foot from the position of one line to the position of the line next above it, where the distance from one line to the next is great, the land is more nearly level, and when it is short the inclination is steeper. For instance, in the southwest corner of the plan, the land is nearly level to the 2-foot line; it rises slowly to the center of the field, and to the eastern side about one-fourth of the distance from the southern boundary, while an elevation coming down between these two valleys, and others skirting the west side of the former one and the southern side of the latter, are indicated by the greater nearness of the lines. The points at which the contour lines cross the section lines are found in the following manner: On the second line from the west side of the field we find the elevations of the 4th, 5th and 6th stakes from the southern boundary to be 1.9, 3.3, and 5.1. The contour lines, representing points of elevation of 2, 3, 4, and 5 feet above the datum line, will cross the 50-foot lines at their intersections, only where these intersections are marked in even feet. When they are marked with fractions of a foot, the lines must be made to cross at points between two intersections,—nearer to one or the other, according to their elevations,—thus between 1.9 and 3.3, the 2-foot and 3-foot contour lines must cross. The total difference of elevation, between the two points is 3.3—1.9=1.4; 10/14 of the space must be given to the even foot between the lines, and the 2-foot line should be 1/14 of the space above the point 1.9;—the 3-foot line will then come 3/14 below the point 3.3. In the same manner, the line from 3.3 to 5.1 is divided into 18 parts, of which 10 go to the space between the 4. and 5. lines, 7 are between 3.3 and the 4-foot line, and 1 between the 5-foot line and 5.1.

With these maps, made from observations taken in the field, we are prepared to lay down, on paper, our system of drainage, and to mature a plan which shall do the necessary work with the least expenditure of labor and material. The more thoroughly this plan is considered, the more economical and effective will be the work. Having already obtained the needed information, and having it all before us, we can determine exactly the location and size of each drain, and arrange, before hand, for a rapid and satisfactory execution of the work. The only thing that may interfere with the perfect application of the plan, is the presence of masses of underground rock, within the depth to which the drains are to be laid.

The slight deviations caused by carrying the drains around large stones, which are found in cutting the ditches, do not affect the general arrangement of the lines.

In most cases, it will be sufficient to have contour lines taken only at intervals of two feet, and, owing to the smallness of the scale on which these maps are engraved, and to avoid complication in the finished plan, where so much else must be shown, each alternate line is omitted. Of course, where drains are at once staked out on the land, by a practiced engineer, no contour lines are taken, as by the aid of the level and rod for the flatter portions, and by the eye alone for the steeper slopes, he will be able at once to strike the proper locations and directions; but for one of less experience, who desires to thoroughly mature his plan before commencing, they are indispensable; and their introduction here will enable the novice to understand, more clearly than would otherwise be possible, the principles on which the plan should be made.

For preliminary examinations, and for all purposes in which great accuracy is not required, the little instrument shown in Fig. 9,—"Wells' Clinometer,"—is exceedingly simple and convenient. Its essential parts are a flat side, or base, on which it stands, and a hollow disk just half filled with some heavy liquid. The glass face of the disk is surrounded by a graduated scale that marks the angle at which the surface of the liquid stands, with reference to the flat base. The line 0.——0. being parallel to the base, when the liquid stands on that line, the flat side is horizontal; the line 90.——90. being perpendicular to the base, when the liquid stands on that line, the flat side is perpendicular or plumb. In like manner, the intervening angles are marked, and, by the aid of the following tables, the instrument indicates the rate of fall per hundred feet of horizontal measurement, and per hundred feet measured upon the sloping line.

The low price at which this instrument is sold, $1.50, places it within the reach of all.

Table No. 1 shows the rise of the slope for 100 feet of the horizontal measurement. Example: If the horizontal distance is 100 feet, and the slope is at an angle of 15°, the rise will be 17-633/1000 feet.

Table No. 2 shows the rise of the slope for 100 feet of its own length. If the sloping line, (at an angle of 15°,) is 100 feet long, it rises 25.882 feet.

With the maps before him, showing the surface features of the field, and the position of the under-ground rock, the drainer will have to consider the following points:

1. Where, and at what depth, shall the outlet be placed?

2. What shall be the location, the length and the depth of the main drain?

3. What subsidiary mains,—or collecting drains,—shall connect the minor valleys with the main?

4. What may best be done to collect the water of large springs and carry it away?

5. What provision is necessary to collect the water that flows over the surface of out-cropping rock, or along springy lines on side hills or under banks?

6. What should be the depth, the distance apart, the direction, and the rate of fall, of the lateral drains?

7. What kind and sizes of tile should be used to form the conduits?

8. What provision should be made to prevent the obstruction of the drains, by an accumulation of silt or sand, which may enter the tiles immediately after they are laid, and before the earth becomes compacted about them; and from the entrance of vermin?

1. The outlet should be at the lowest point of the boundary, unless, (for some especial reason which does not exist in the case under consideration, nor in any usual case,) it is necessary to seek some other than the natural outfall; and it should be deep enough to take the water of the main drain, and laid on a sufficient inclination for a free flow of the water. It should, where sufficient fall can be obtained without too great cost, deliver this water over a step of at least a few inches in height, so that the action of the drain may be seen, and so that it may not be liable to be clogged by the accumulation of silt, (or mud,) in the open ditch into which it flows.

2. The main drain should, usually, be run as nearly in the lowest part of the principal valley as is consistent with tolerable straightness. It is better to cut across the point of a hill, to the extent of increasing the depth for a few rods, than to go a long distance out of the direct course to keep in the valley, both because of the cost of the large tile used in the main, and of the loss of fall occasioned by the lengthening of the line. The main should be continued from the outlet to the point at which it is most convenient to collect the more remote sub-mains, which bring together the water of several sets of laterals. As is the case in the tract under consideration, the depth of the main is often restricted, in nearly level land, toward the upper end of the flat which lies next to the outlet, by the necessity for a fall and the difficulty which often exists in securing a sufficiently low outlet. In such case, the only rule is to make it as deep as possible. When the fall is sufficient, it should be placed at such depth as will allow the laterals and sub-mains which discharge into it to enter at its top, and discharge above the level of the water which flows through it.

3. Subsidiary mains, or sub-mains, connecting with the main drains, should be run up the minor valleys of the land, skirting the bases of the hills. Where the valley is a flat one, with rising ground at each side, there should be a sub-main, to receive the laterals from each hill side. As a general rule, it may be stated, that the collecting drain at the foot of a slope should be placed on the line which is first reached by the water flowing directly down over its surface, before it commences its lateral movement down the valley; and it should, if possible, be so arranged that it shall have a uniform descent for its whole distance. The proper arrangement of these collecting drains requires more skill and experience than any other branch of the work, for on their disposition depends, in a great measure, the economy and success of the undertaking.

4. Where springs exist, there should be some provision made for collecting their water in pits filled with loose stone, gravel, brush or other rubbish, or furnished with several lengths of tile set on end, one above the other, or with a barrel or other vessel; and a line of tile of proper size should be run directly to a main, or sub-main drain. The manner of doing this by means of a pit filled with stone is shown in Fig. 10. The collection of spring water in a vertical tile basin is shown in Fig. 11.

5. Where a ledge of shelving rock, of considerable size, occurs on land to be drained, it is best to make some provision for collecting, at its base, the water flowing over its surface, and taking it at once into the drains, so that it may not make the land near it unduly wet. To effect this, a ditch should be dug along the base of the rock, and quite down to it, considerably deeper than the level of the proposed drainage; and this should be filled with small stones to that level, with a line of tile laid on top of the stones, a uniform bottom for the tile to rest upon being formed of cheap strips of board. The tile and stone should then be covered with inverted sods, with wood shavings, or with other suitable material, which will prevent the entrance of earth, (from the covering of the drain,) to choke them. The water, following down the surface of the rock, will rise through the stone work and, entering the tile, will flow off. This method may be used for springy hill sides.

6. The points previously considered relate only to the collection of unusual quantities of water, (from springs and from rock surfaces,) and to the removal from the land of what is thus collected, and of that which flows from the minor or lateral drains.

The lateral drains themselves constitute the real drainage of the field, for, although main lines take water from the land on each side, their action in this regard is not usually considered, in determining either their depth or their location, and they play an exceedingly small part in the more simple form of drainage,—that in which a large tract of land, of perfectly uniform slope, is drained by parallel lines of equal length, all discharging into a single main, running across the foot of the field. The land would be equally well drained, if the parallel lines were continued to an open ditch beyond its boundary,—the main tile drain is only adopted for greater convenience and security. It will simplify the question if, in treating the theory of lateral drains, it be assumed that our field is of this uniform inclination, and admits of the use of long lines of parallel drains. In fact, it is best in practice to approximate as nearly as possible to this arrangement, because deviations from it, though always necessary in broken land, are always more expensive, and present more complicated engineering problems. If all the land to be drained had a uniform fall, in a single direction, there would be but little need of engineering skill, beyond that which is required to establish the depth, fall, and distance apart, at which the drains should be laid. It is chiefly when the land pitches in different directions, and with varying inclination, that only a person skilled in the arrangement of drains, or one who will give much consideration to the subject, can effect the greatest economy by avoiding unnecessary complication, and secure the greatest efficiency by adjusting the drains to the requirements of the land.

Assuming the land to have an unbroken inclination, so as to require only parallel drains, it becomes important to know how these parallel drains, (corresponding to the lateral drains of an irregular system,) should be made.

The history of land draining is a history of the gradual progress of an improvement, from the accomplishment of a single purpose, to the accomplishment of several purposes, and most of the instruction which modern agricultural writers have given concerning it, has shown too great dependence upon the teachings of their predecessors, who considered well the single object which they sought to attain, but who had no conception that draining was to be so generally valuable as it has become. The effort, (probably an unconscious one,) to make the theories of modern thorough-draining conform to those advanced by the early practitioners, seems to have diverted attention from some more recently developed principles, which are of much importance. For example, about a hundred years ago, Joseph Elkington, of Warwickshire, discovered that, where land is made too wet by under-ground springs, a skillful tapping of these,—drawing off their water through suitable conduits,—would greatly relieve the land, and for many years the Elkington System of drainage, being a great improvement on every thing theretofore practiced, naturally occupied the attention of the agricultural world, and the Board of Agriculture appointed a Mr. Johnstone to study the process, and write a treatise on the subject.

Catch-water drains, made so as to intercept a flow of surface water, have been in use from immemorial time, and are described by the earliest writers. Before the advent of the Draining Tile, covered drains were furnished with stones, boards, brush, weeds, and various other rubbish, and their good effect, very properly, claimed the attention of all improvers of wet land. When the tile first made its appearance in general practice, it was of what is called the "horse-shoe" form, and,—imperfect though it was,—it was better than anything that had preceded it, and was received with high approval, wherever it became known. The general use of all these materials for making drains was confined to a system of partial drainage, until the publication of a pamphlet, in 1833, by Mr. Smith, of Deanston, who advocated the drainage of the whole field, without reference to springs. From this plan, but with important modifications in matters of detail, the modern system of tile draining has grown. Many able men have aided its progress, and have helped to disseminate a knowledge of its processes and its effects, yet there are few books on draining, even the most modern ones, which do not devote much attention to Elkington's discovery; to the various sorts of stone and brush drains; and to the manufacture and use of horse-shoe tile;—not treating them as matters of antiquarian interest, but repeating the instructions for their application, and allowing the reasoning on which their early use was based, to influence, often to a damaging extent, their general consideration of the modern practice of tile draining.

These processes are all of occasional use, even at this day, but they are based on no fixed rules, and are so much a matter of traditional knowledge, with all farmers, that instruction concerning them is not needed. The kind of draining which is now under consideration, has for its object the complete removal of all of the surplus water that reaches the soil, from whatever source, and the assimilation of all wet soils to a somewhat uniform condition, as to the ease with which water passes through them.

There are instances, as has been shown, where a large spring, overflowing a considerable area, or supplying the water of an annoying brook, ought to be directly connected with the under-ground drainage, and its flow neatly carried away; and, in other cases, the surface flow over large masses of rock should be given easy entrance into the tile; but, in all ordinary lands, whether swamps, springy hill sides, heavy clays, or light soils lying on retentive subsoil, all ground, in fact, which needs under-draining at all, should be laid dry above the level to which it is deemed best to place the drains;—not only secured against the wetting of springs and soakage water, but rapidly relieved of the water of heavy rains. The water table, in short, should be lowered to the proper depth, and, by permanent outlets at that depth, be prevented from ever rising, for any considerable time, to a higher level. This being accomplished, it is of no consequence to know whence the water comes, and Elkington's system need have no place in our calculations. As round pipes, with collars, are far superior to the "horse-shoe" tiles, and are equally easy to obtain, it is not necessary to consider the manner in which these latter should be used,—only to say that they ought not to be used at all.

The water which falls upon the surface is at once absorbed, settles through the ground, until it reaches a point where the soil is completely saturated, and raises the general water level. When this level reaches the floor of the drains, the water enters at the joints and is carried off. That which passes down through the land lying between the drains, bears down upon that which has already accumulated in the soil, and forces it to seek an outlet by rising into the drains.

Except from quite near to the drain, it is not probable that the water in the soil runs laterally towards it.

Having provided boning-rods, which are strips of board 7 feet long, having horizontal cross pieces at their upper ends, (see Fig. 29,) set these perpendicularly on the spots which have been found by measurement to be at the correct depth opposite stakes 10, 11, 12, 15, and 17, and fasten each in its place by wedging it between two strips of board laid across the ditch, so as to clasp it, securing these in their places by laying stones or earth upon their ends.

As these boning-rods are all exactly 7 feet long, of course, a line sighted across their tops will be exactly 7 feet higher, at all points, than the required grade of the ditch directly beneath it, and if a plumb rod, (similar to the boning-rod, but provided with a line and plummet,) be set perpendicularly on any point of the bottom of the drain, the relation of its cross piece to the line of sight across the tops of the boning-rods will show whether the bottom of the ditch at that point is too high, or too low, or just right. The manner of sighting over two boning-rods and an intermediate plumb-rod, is shown in Fig. 31.

Three persons are required to finish the bottom of the ditch; one to sight across the tops of the boning-rods, one to hold the plumb-rod at different points as the finishing progresses, and one in the ditch, (see Fig. 30,) provided with the finishing spade and scoop,—and, in hard ground, with a pick,—to cut down or fill up as the first man calls "too high," or, "too low." An inch or two of filling maybe beaten sufficiently hard with the back of the scoop, but if several inches should be required, it should be well rammed with the top of a pick, or other suitable instrument, as any subsequent settling would disarrange the fall.

As the lateral drains are to be laid first, they should be the first graded, and as they are arranged to discharge into the tops of the mains, their water will still flow off, although the main ditches are not yet reduced to their final depth. After the laterals are laid and filled in, the main should be graded, commencing at the upper end; the tiles being laid and covered as fast as the bottom is made ready, so that it may not be disturbed by the water of which the main carries so much more than the laterals.

Tile-Laying.—Gisborne says: "It would be scarcely more absurd to set a common blacksmith to eye needles than to employ a common laborer to lay pipes and collars." The work comes under the head of skilled labor, and, while no very great exercise of judgment is required in its performance, the little that is required is imperatively necessary, and the details of the work should be deftly done. The whole previous outlay,—the survey and staking of the field, the purchase of the tiles, the digging and grading of the ditches—has been undertaken that we may make the conduit of earthenware pipes which is now to be laid, and the whole may be rendered useless by a want of care and completeness in the performance of this chief operation. This subject, (in connection with that of finishing the bottoms of the ditches,) is very clearly treated in Mr. Hoskyns' charming essay,

"Talpa, or the Chronicles of a Clay Farm."

"It was urged by Mr. Brunel, as a justification for more attention and expense in the laying of the rails of the Great Western, than had been ever thought of upon previously constructed lines, that all the embankments and cuttings, and earthworks and stations, and law and parliamentary expenses—in fact, the whole of the outlay encountered in the formation of a railway, had for its main and ultimate object a perfectly smooth and level line of rail; that to turn stingy at this point, just when you had arrived at the great ultimatum of the whole proceedings, viz: the iron wheel-track, was a sort of saving which evinced a want of true preception of the great object of all the labor that had preceded it. It may seem curious to our experiences, in these days, that such a doctrine could ever have needed to be enforced by argument; yet no one will deem it wonderful who has personally witnessed the unaccountable and ever new difficulty of getting proper attention paid to the leveling of the bottom of a drain, and the laying of the tiles in that continuous line, where one single depression or irregularity, by collecting the water at that spot, year after year, tends toward the eventual stoppage of the whole drain, through two distinct causes, the softening of the foundation underneath the sole, or tile flange, and the deposit of soil inside the tile from the water collected at the spot, and standing there after the rest had run off. Every depression, however slight, is constantly doing this mischief in every drain where the fall is but trifling; and if to the two consequences above mentioned, we may add the decomposition of the tile itself by the action of water long stagnant within it, we may deduce that every tile-drain laid with these imperfections in the finishing of the bottom, has a tendency toward obliteration, out of all reasonable proportion with that of a well-burnt tile laid on a perfectly even inclination, which, humanly speaking, may be called a permanent thing. An open ditch cut by the most skillful workman, in the summer, affords the best illustration of this underground mischief. Nothing can look smoother and more even than the bottom, until that uncompromising test of accurate levels, the water, makes its appearance: all on a sudden the whole scene is changed, the eye-accredited level vanishes as if some earthquake had taken place: here, there is a gravelly scour, along which the stream rushes in a thousand little angry-looking ripples; there, it hangs and looks as dull and heavy as if it had given up running at all, as a useless waste of energy; in another place, a few dead leaves or sticks, or a morsel of soil broken from the side, dams back the water for a considerable distance, occasioning a deposit of soil along the whole reach, greater in proportion to the quantity and the muddiness of the water detained. All this shows the paramount importance of perfect evenness in the bed on which the tiles are laid. The worst laid tile is the measure of the goodness and permanence of the whole drain, just as the weakest link of a chain is the measure of its strength."

The simple laying of the smaller sizes of pipes and collars in the lateral drains, is an easy matter. It requires care and precision in placing the collar equally under the end of each pipe, (having the joint at the middle of the collar,) in having the ends of the pipes actually touch each other within the collars, and in brushing away any loose dirt which may have fallen on the spot on which the collar is to rest. The connection of the laterals with the mains, the laying of the larger sizes of tiles so as to form a close joint, the wedging of these larger tiles firmly into their places, and the trimming which is necessary in going around sharp curves, and in putting in the shorter pieces which are needed to fill out the exact length of the drain, demand more skill and judgment than are often found in the common ditcher. Still, any clever workman, who has a careful habit, may easily be taught all that is necessary; and until he is thoroughly taught,—and not only knows how to do the work well, but, also, understands the importance of doing it well,—the proprietor should carefully watch the laying of every piece.

Never have tiles laid by the rod, but always by the day. "The more haste, the less speed," is a maxim which applies especially to tile-laying.

If the proprietor or the engineer does not overlook the laying of each tile as it is done, and probably he will not, he should carefully inspect every piece before it is covered. It is well to walk along the ditches and touch each tile with the end of a light rod, in such a way as to see whether it is firm enough in its position not to be displaced by the earth which will fall upon it in filling the ditches.

Preparatory to laying, the tiles should be placed along one side of the ditch, near enough to be easily reached by a man standing in it. When collars are to be used, one of these should be slipped over one end of each tile. The workman stands in the ditch, with his face toward its upper end. The first tile is laid with a collar on its lower end, and the collar is drawn one-half of its length forward, so as to receive the end of the next tile. The upper end of the first tile is closed with a stone, or a bit of broken tile placed firmly against it. The next tile has its nose placed into the projecting half of the collar of the first one, and its own collar is drawn forward to receive the end of the third, and thus to the end of the drain, the workman walking backward as the work progresses. By and by, when he comes to connect the lateral with the main, he may find that a short piece of tile is needed to complete the length; this should not be placed next to the tile of the main, where it is raised above the bottom of the ditch, but two or three lengths back, leaving the connection with the main to be made with a tile of full length. If the piece to be inserted is only two or three inches long, it may be omitted, and the space covered by using a whole 2½-inch tile in place of the collar. In turning corners or sharp curves, the end of the tile may be chipped off, so as to be a little thinner on one side, which will allow it to be turned at a greater angle in the collar.

If the drain turns a right angle, it will be better to dig out the bottom of the ditch to a depth of about eight inches, and to set a 6-inch tile on end in the hole, perforating its sides, so as to admit the ends of the pipes at the proper level. This 6-inch tile, (which acts as a small silt-basin,) should stand on a board or on a flat stone, and its top should be covered with a stone or with a couple of bricks. Wood will last almost forever below the level of the drain, where it will always be saturated with water, but in the drier earth above the tile, it is much more liable to decay.

The trimming and perforating of the tile is done with a "tile-pick," (Fig. 32,) the hatchet end, tolerably sharp, being used for the trimming, and the point, for making the holes. This is done by striking lightly around the circumference of the hole until the center piece falls in, or can be easily knocked in. If the hole is irregular, and does not fit the tile nicely, the open space should be covered with bits of broken tile, to keep the earth out.

As fast as the laterals are laid and inspected, they should be filled in to the depth of at least a foot, to protect the tiles from being broken by the falling of stones or lumps of earth from the top, and from being displaced by water flowing in the ditch. Two or three feet of the lower end may be left uncovered until the connection with the main is finished.

In the main drains, when the tiles are of the size with which collars are used, the laying is done in the same manner. If it is necessary to use 3-1/2-inch tiles, or any larger size, much more care must be given to the closing of the joints. All tiles, in manufacture, dry more rapidly at the top, which is more exposed to the air, than at the bottom, and they are, therefore, contracted and made shorter at the top. This difference is most apparent in the larger sizes. The large round tiles, which can be laid on any side, can easily be made to form a close joint, and they should be secured in their proper position by stones or lumps of earth, wedged in between them and the sides of the ditch. The sole tiles must lie with the shortest sides up, and, usually, the space between two tiles, at the top, will be from one-quarter to one-half of an inch. To remedy this defect, and form a joint which may he protected against the entrance of earth, the bottom should he trimmed off, so as to allow the tops to come closer together. Any opening, of less than a quarter of an inch, can he satisfactorily covered,—more than that should not be allowed. In turning corners, or in passing around curves, with large tiles, their ends must he beveled off with the pick, so as to fit nicely in this position.

The best covering for the joints of tiles which are laid without collars, is a scrap of tin, bent so as to fit their shape,—scraps of leather, or bits of strong wood shavings, answer a very good purpose, though both of these latter require to be held in place by putting a little earth over their ends as soon as laid on the tile. Very small grass ropes drawn over the joints, (the ends being held down with stones or earth,) form a satisfactory covering, but care should be taken that they be not too thick. A small handful of wood shavings, thrown over the joints, also answers a good purpose. Care, however, should always be taken, in using any material which will decay readily, to have no more than is necessary to keep the earth out, lest, in its decay, it furnish material to be carried into the tile and obstruct the flow. This precaution becomes less necessary in the case of drains which always carry considerable streams of water, but if they are at times sluggish in their flow, too much care cannot be given to keep them free of all possible causes of obstruction. As nothing is gained by increasing the quantity of loose covering beyond what is needed to close the joints, and as such covering is only procured with some trouble, there is no reason for its extravagant use.

There seems to remain in the minds of many writers on drainage a glimmering of the old fallacy that underdrains, like open drains, receive their water from above, and it is too commonly recommended that porous substances be placed above the tile. If, as is universally conceded, the water rises into the tile from below, this is unnecessary. The practice of covering the joints, and even covering the whole tile, (often to the depth of a foot,) with tan-bark, turf, coarse gravel, etc., is in no wise to be commended; and, while the objections to it are not necessarily very grave in all cases, it always introduces an element of insecurity, and it is a waste of money, if nothing worse.

The tile layer need not concern himself with the question, of affording entrance room for the water. Let him, so far as the rude materials at hand will allow, make the joints perfectly tight, and when the water comes, it will find ample flaws in his work, and he will have been a good workman if it do not find room to flow in a current, carrying particles of dirt with it.

In ditches in which water is running at the time of laying the tiles, the process should follow closely after the grading, and the stream may even be dammed back, section after section, (a plugged tile being placed under the dam, to be afterwards replaced by a free one,) and graded, laid and covered before the water breaks in. There is one satisfaction in this kind of work,—that, while it is difficult to lay the drain so thoroughly well as in a dry ditch, the amount of water is sufficient to overcome any slight tendency to obstruction.

Connections.—As has been before stated, lateral drains should always enter at the top of the main. Even in the most shallow work, the slightly decreased depth of the lateral, which this arrangement requires, is well compensated for by the free outlet which it secures.

After the tile of the main, which is to receive a side drain, has been fitted to its place, and the point of junction marked, it should be taken up and perforated; then the end of the tile of the lateral should be so trimmed as to fit the hole as accurately as may be, the large tile replaced in its position, and the small one laid on it,—reaching over to the floor of the lateral ditch. Then connect it with the lateral as previously laid, fill up solidly the space under the tile which reaches over to the top of the main, (so that it cannot become disturbed in filling,) and lay bits of tile, or other suitable covering, around the connecting joint.

When chips of tile, or similar matters, are used to cover openings in the tile-work, it is well to cover them at once with a mortar made of wet clay, which will keep them in place until the ditches are filled.

When the main drain is laid with collars, it should be so arranged that, by substituting a full tile in the place of the collar,—leaving, within it, a space between the smaller pipes,—a connection can be made with this larger tile, as is represented in Figures 33 and 34.

Silt-Basins should be used at all points where a drain, after running for any considerable distance at a certain rate of fall, changes to a less rapid fall,—unless, indeed, the diminished fall be still sufficiently great for the removal of silty matters, (say two feet or more in a hundred). They may be made in any manner which will secure a stoppage of the direct current, and afford room below the floor of the tile for the deposit of the silt which the water has carried in suspension; and they may be of any suitable material;—even a sound flour barrel will serve a pretty good purpose for many years. The most complete form of basin is that represented in Figure 24.

When the object is only to afford room for the collection of the silt of a considerable length of drain, and it is not thought worth while to keep open a communication with the surface, for purposes of inspection, a square box of brick work, (Fig. 35,) having a depth of one and a half or two feet below the floor of the drain,—tiles for the drains being built in the walls, and the top covered with a broad stone,—will answer very well.

A good sort of basin, to reach to the surface of the ground, may be made of large, vitrified drain pipes,—such as are used for town sewerage,—having a diameter of from six to twelve inches, according to the requirements of the work. This basin is shown in Figure 36.

Figure 37 represents a basin made of a 6-inch tile,—similar to that described on page 130, for turning a short corner. A larger basin of the same size, cheaper than if built of brick, may be made by using a large vitrified drain pipe in the place of the one shown in the cut. These vitrified pipes may be perforated in the manner described for the common tile.

In laying the main line C, (Fig. 21,) an underground basin of brick work, (Fig. 35,) or its equivalent, should be placed at stake 7, because at that point the water, which has been flowing on an inclination of 1.09, 2.00 and 2.83 per 100, continues its course over the much less fall of only 0.56 per 100.

If, among the tiles which have passed the inspection, there are some which, from over burning, are smaller than the average, they should be laid at the upper ends of the laterals. The cardinal rule of the tile layer should be never to have a single tile in the finished drain of smaller size, of more irregular shape, or less perfectly laid, than any tile above it. If there is to be any difference in the quality of the drain, at different points, let it grow better as it approaches the outlet and has a greater length above depending upon its action.

Covering the Tiles, and Filling-in the Ditches.—The best material for covering the tiles is that which will the most completely surround them, so as to hold them in their places; will be the least likely to have passages for the flow of streams of water into the joints, and will afford the least silt to obstruct the drain. Clay is the best of all available materials, because it is of the most uniform character throughout its mass, and may be most perfectly compacted around the tiles. As has been before stated, all matters which are subject to decay are objectionable, because they will furnish fine matters to enter the joints, and by their decrease of bulk, may leave openings in the earth through which streams of muddy water may find their way into the tiles. Gravel is bad, and will remain bad until its spaces are filled with fine dirt deposited by water, which, leaving only a part of its impurities here, carries the rest into the drain. A gravelly loam, free from roots or other organic matter, if it is strong enough to be worked into a ball when wet, will answer a very good purpose.

Ordinarily, the earth which was thrown out from the bottom of the ditch, and which now lies at the top of the dirt heap, is the best to be returned about the tiles, being first freed from any stones it may contain which are large enough to break or disturb the tiles in falling on to them.

If the bottom of the ditch consists of quicksand or other silty matters, clay or some other suitable earth should be sought in that which was excavated from a less depth, or should be brought from another place. A thin layer of this having been placed in the bottom of the ditch when grading, a slight covering of the same about the tiles will so encase them as to prevent the entrance of the more "slippy" soil.

The first covering of fine earth, free from stones and clods, should be sprinkled gently over the tiles, no full shovelfuls being thrown on to them until they are covered at least six inches deep. When the filling has reached a height of from fifteen to twenty inches, the men may jump into the ditch and tramp it down evenly and regularly, not treading too hard in any one place at first. When thus lightly compacted about the tile, so that any further pressure cannot displace them, the filling should be repeatedly rammed, (the more the better,) by two men standing astride the ditch, facing each other, and working a maul, such as is shown in Figure 38, and which may weigh from 80 to 100 pounds.

Those to whom this recommendation is new, will, doubtless, think it unwise. The only reply to their objection must be that others who shared their opinion, have, by long observation and experience, been convinced of its correctness. They may practically convince themselves of the value of this sort of covering by a simple and inexpensive experiment: Take two large, water-tight hogsheads, bore through the side of each, a few inches from the bottom, a hole just large enough to admit a 1-1/4-inch tile; cover the bottom to the hight of the lower edge of the hole with strong, wet clay, beaten to a hard paste; on this, lay a line of pipes and collars,—the inner end sealed with putty, and the tile which passes through the hole so wedged about with putty, that no water could pass out between it and the outside of the hole. Cover the tile in one hogshead with loose gravel, and then fill it to the top with loose earth. Cover the tile in the other, twenty inches deep, with ordinary stiff clay, (not wet enough to puddle, but sufficiently moist to pack well,) and ram it thoroughly, so as to make sure that the tiles are completely clasped, and that there is no crack nor crevice through which water can trickle, and then fill this hogshead to the top with earth, of the same character with that used in the other case. These hogsheads should stand where the water of a small roof, (as that of a hog-pen,) may be led into them, by an arrangement which shall give an equal quantity to each;—this will give them rather more than the simple rain-fall, but will leave them exposed to the usual climatic changes of the season. A vessel, of a capacity of a quart or more, should be connected with each outlet, and covered from the dust,— these will act as silt-basins. During the first few storms the water will flow off much more freely from the first barrel; but, little by little, the second one, as the water finds its way through the clay, and as the occasional drying, and repeated filtration make it more porous, will increase in its flow until it will, by the end of the season, or, at latest, by the end of the second season, drain as well as the first, if, indeed, that be not by this time somewhat obstructed with silt. The amount of accumulation in the vessels at the outlet will show which process has best kept back the silt, and the character of the deposit will show which would most probably be carried off by the gentle flow of water in a nearly level drain.

It is no argument against this experiment that its results cannot be determined even in a year, for it is not pretended that drains laid in compact clay will dry land so completely during the first month as those which give more free access to the water; only that they will do so in a comparatively short time; and that, as drainage is a work for all time, (practically as lasting as the farm itself,) the importance of permanence and good working for long years to come, is out of all proportion to that of the temporary good results of one or two seasons, accompanied with doubtful durability.

It has been argued that surface water will be more readily removed by drains having porous filling. Even if this were true to any important degree,—which it is not,—it would be an argument against the plan, for the remedy would be worse than the disease. If the water flow from the surface down into the drain, it will not fail to carry dirt with it, and instead of the clear water, which alone should rise into the tiles from below, we should have a trickling flow from above, muddy with wasted manure and silty earth.

The remaining filling of the ditch is a matter of simple labor, and may be done in whatever way may be most economical under the circumstances of the work. If the amount to be filled is considerable, so that it is desirable to use horse-power, the best way will be to use a scraper, such as is represented in Figure 39, which is a strongly ironed plank, 6 feet long and 18 inches wide, sharp shod at one side, and supplied with handles at the other. It is propelled by means of the curved rods, which are attached to its under side by flexible joints. These rods are connected by a chain which has links large enough to receive the hook of an ox-chain. This scraper may be used for any straight-forward work by attaching the power to the middle of the chain. By moving the hook a few links to the right or left, it will act somewhat after the manner of the mould-board of a plow, and will, if skillfully handled, shoot the filling rapidly into the ditch.

If the work is done by hand, mix the surface soil and turf with the subsoil filling for the whole depth. If with a scraper, put the surface soil at the bottom of the loose filling, and the subsoil at the top, as this will be an imitation, for the limited area of the drains, of the process of "trenching," which is used in garden cultivation.

When the ditches are filled, they will be higher than the adjoining land, and it will be well to make them still more so by digging or plowing out a small trench at each side of the drain, throwing the earth against the mound, which will prevent surface water, (during heavy rains,) from running into the loose filling before it is sufficiently settled. A cross section of a filled drain provided with these ditches is shown in Figure 40.

In order that the silt-basins may be examined, and their accumulations of earth removed, during the early action of the drains, those parts of the ditches which are above them may be left open, care being taken, by cutting surface ditches around them, to prevent the entrance of water from above. During this time the covers of the basins should be kept on, and should be covered with inverted sods to keep loose dirt from getting into them.

Collecting the Water ©f Springs.—The lateral which connects with the main drain, A, (Fig. 21,) at the point m, and which is to take the water of the spring at the head of the brook, should not be opened until the main has been completed and filled into the silt-basin,—the brook having, meantime, been carried over the other ditches in wooden troughs. This lateral may now be made in the following way: Dig down to the tile of the main, and carry the lateral ditch back, a distance of ten feet. In the bottom of this, place a wooden trough, at least six feet long, laid at such depth that its channel shall be on the exact grade required for laying the tiles, and lay long straw, (held down by weights,) lengthwise within it. Make an opening in the tile of the main and connect the trough with it. The straw will prevent any coarse particles of earth from being carried into the tile, and the flow of the water will be sufficient to carry on to the silt-basin any finer matters. Now open the ditch to and beyond the spring, digging at least a foot below the grade in its immediate vicinity, and filling to the exact grade with small stones, broken bricks, or other suitable material. Lay the tiles from the upper end of the ditch across the stone work, and down to the wooden trough. Now spread a sufficient layer of wood shavings over the stone work to keep the earth from entering it, cover the tiles and fill in the ditch, as before directed, and then remove the straw from the wooden trough and lay tiles in its place. In this way, the water of even a strong spring may be carried into a finished drain without danger. In laying the tile which crosses the stone work, it is well to use full 2-1/2-inch tiles in the place of collars, leaving the joints of these, and of the 1-1/4-inch tiles, (which should join near the middle of the collar tile,) about a quarter of an inch open, to give free entrance to the water.

The stone and tile drain, H, I, is simply dug out to the surface of the rock, if this is not more than two feet below the grade of the upper ends of the laterals with which it connects, and then filled up with loose stones to the line of grade. If the stones are small, so as to form a good bottom for the tiles, they may be laid directly upon it; if not, a bottom for them may be made of narrow strips of cheap boards. Before filling, the tiles and stone work should be covered with shavings, and the filling above these should consist of a strong clay, which will remain in place after the shavings rot away.

Amending the Map.—When the tiles are laid, and before they are covered, all deviations of the lines, as in passing around large stones and other obstructions, which may have prevented the exact execution of the original plan, and the location and kind of each underground silt-basin should also be carefully noted, so that they may be transferred to the map, for future reference, in the event of repairs becoming necessary. In a short time after the work is finished, the surface of the field will show no trace of the lines of drain, and it should be possible, in case of need, to find any point of the drains with precision, so that no labor will be lost in digging for it. It is much cheaper to measure over the surface than to dig four feet trenches through the ground.

Concerning the amount of work that one man can do in a day, in different soils, digging ditches 4 feet deep, French says: "In the writer's own field, where the pick was used to loosen the lower two feet of earth, the labor of opening and filling drains 4 feet deep, and of the mean width of 14 inches, all by hand labor, has been, in a mile of drains, being our first experiments, about one day's labor to 3 rods in length. The excavated earth of such a drain measures not quite 3 cubic yards, (exactly, 2.85.)" In a subsequent work, in a sandy soil, two men opened, laid, and refilled 14 rods in one day;—the mean width being 12 inches.

Surely such soil ought not to require thorough draining; where men can go so easily, water ought to find its way alone.

"In the same season, the same men opened, laid, and filled 70 rods of 4-foot drain of the same mean width of 12 inches, in the worst kind of clay soil, where the pick was constantly used. It cost 35 days' labor to complete the job, being 50 cents per rod for the labor alone." Or, under the foregoing calculation of $1.50 per day, 75 cents per rod. These estimates, in common with nearly all that are published, are for the entire work of digging, grading, tile-laying, and refilling. Deducting the time required for the other work, the result will be about as above estimated; for the rough excavation, 3 1/2-rods to the day's work, costing, at $1.50 per day, 43 cents to the rod.

Grading is the removal of 2 or 3 inches in depth, and about 4 inches in width, of the soil at the bottom of the ditch. It is chiefly done with the finishing scoop, which, (being made of two thin plates, one of iron and one of steel, welded together, the iron wearing away and leaving the sharp steel edge always prominent,) will work in a very hard clay without the aid of the pick. Three men,—the one in the ditch being a skillful workman, and the others helping him when not sighting the rods,—will grade about 100 rods per day, making the cost about 6 cents per rod. Until they acquire the skill to work thus rapidly, they should not be urged beyond what they can readily do in the best manner, as this operation, (which is the preparing of the foundation for the tiles,) is probably the most important of the whole work of draining.

Tiles and Tile-Laying.—After allowing for breakage, it will take about 16 tiles and 16 collars to lay a rod in length of drain. The cost of these will, of course, be very much affected by the considerations of the nearness of the tile-kiln and the cost of transportation. They should, in no ordinary case, cost, delivered on the ground, more than $8 per thousand for 1-1/4-inch tiles, and $4 per thousand for the collars, making a total of $12 for both, equal to about 19 cents per rod. The laying of the tiles, may be set down at 2 cents per rod,—based on a skilled man laying 100 rods daily, and receiving $2 per day.

Covering and filling will probably cost 10 cents per rod, (if the scraper, Fig. 39, can be successfully used for the rough filling, the cost will be reduced considerably below this.)

The four items of the cost of making one rod of lateral drain are as follows:

If the drains are placed at intervals of 40 feet, there are required 64 rods to the acre,—this at 80 cents per rod will make the cost per acre,—for the above items,—$51.20.

The Exclusion of the Sea is of the first importance, because not only does it saturate the land with water,—but this water, being salt, renders it unfertile for the plants of ordinary cultivation, and causes it to produce others which are of little, or no value.

The only means by which the sea may be kept out is, by building such dykes or embankments as shut out the highest tides, and, on shores which are exposed to the action of the waves, will resist their force. Ordinarily, the best, because the cheapest, material of which these embankments can be made, is the soil of the marsh itself. This is rarely,—almost never,—a pure peat, such as is found in upland swamps; it contains a large proportion of sand, blue clay, muscle mud, or other earthy deposits, which give it great weight and tenacity, and render it excellent for forming the body of the dyke. On lands which are overflowed to a considerable extent at each high tide, (twice a day,) it will be necessary to adopt more expensive, and more effective measures, but on ordinary salt meadows, which are deeply covered only at the spring tides, (occurring every month,) the following plan will be found practical and economical.

Locating the line of the embankment far enough back from the edge of the meadow to leave an ample flat outside of it to break the force of the waves, if on the open coast, or to resist the inroads of the current if on the bank of an estuary or a river,—say from ten to one hundred yards, according to the danger of encroachment,—set a row of stakes parallel to the general direction of the shore, to mark the outside line of the base of the dyke. Stake out the inside line at such distance as will give a pitch or inclination to the slopes of one and a half to one on the outside, and of one to one on the inside, and will allow the necessary width at the top, which should be at least two feet higher than the level of the highest tide that is known ever to have occurred at that place. The width of the top should never be less than four feet, and in exposed localities it should be more. If a road will be needed around the land, it is best, if a heavy dyke is required, to make it wide enough to answer this purpose, with still wider places, at intervals, to allow vehicles to turn or to pass each other. Ordinarily, however, especially if there be a good stretch of flat meadow in front, the top of the dyke need not be more than four feet wide. Supposing such a dyke to be contemplated where the water has been known to rise two feet above the level of the meadows, requiring an embankment four feet high, it will be necessary to allow for the base a width of fourteen feet;—four feet for the width of the top, six feet for the reach of the front slope, (1-1/2 to 1,) and four feet for the reach of the back slope, (1 to 1.)

Having staked out two parallel lines, fourteen feet apart, and erected, at intervals of twenty or thirty feet, frames made of rough strips of board of the exact shape of the section of the proposed embankment, the workmen may remove the sod to a depth of six inches, laying it all on the outside of the position of the proposed embankment. The sod from the line of the ditch, from which the earth for the embankment is to be taken, should also be removed and placed with the other. This ditch should be always inside of the dyke, where it will never be exposed to the action of the sea. It should be, at the surface, broader than the base of the dyke, and five feet deep in the center, but its sides may slope from the surface of the ground directly to the center line of the bottom. This is the best form to give it, because, while it should be five feet deep, for future uses as a drain, its bottom need have no width. The great width at the surface will give such a pitch to the banks as to ensure their stability, and will yield a large amount of sod for the facing of the dyke. The edge of this ditch should be some feet away from the inner line of the embankment, leaving it a firm support or shoulder at the original level of the ground, the sod not being removed from the interval. The next step in the work should be to throw, or wheel, the material from the ditch on to the place which has been stripped for the dyke, building it up so as to conform exactly to the profile frames, these remaining in their places, to indicate the filling necessary to make up for the settling of the material, as the water drains out of it.

As fast as a permanent shape can be given to the outer face of the dyke, it should be finished by having the sod placed against it, being laid flatwise, one on top of another, (like stone work,) in the most solid manner possible. This should be continued to the top of the slope, and the flat top of the dyke should also be sodded,—the sods on the top, and on the slope, being firmly beaten to their places with the back of the spade or other suitable implement. This will sufficiently protect the exposed parts of the work against the action of any waves that may be formed on the flat between the dyke and the deep water, while the inner slope and the banks of the ditch, not being exposed to masses of moving water, will retain their shape and will soon be covered with a new growth.

The ends of the work, while the operations are suspended during spring tides, will need an extra protection of sods, but that lying out of reach of the eddies that will be formed by the receding water will not be materially affected.

In the vicinity of cities and towns, however, where more wealth has accumulated, and where the number of persons subjected to the malarial influence is greater, there can be no question as to the propriety of draining, even if nothing but improved health be the object.

Then again, there are immense tracts near the large cities of this country which would be most desirable for residence, were it not that their occupancy, except with certain constant precautions, implies almost inevitable suffering from fever-and-ague, or neuralgia.

Very few neighborhoods within thirty miles of the city of New York are entirely free from these scourges, whose influence has greatly retarded their occupation by those who are seeking country homes; while many, who have braved the dangers of disease in these localities, have had sad cause to regret their temerity.

Probably the most striking instance of the effect of malaria on the growth and settlement of suburban districts, is to be found on Staten Island. Within five miles of the Battery; accessible by the most agreeable and best managed ferry from the city; practically, nearer to Wall street than Murray Hill is; with most charming views of land and water; with a beautifully diversified surface, and an excellent soil; and affording capital opportunities for sea bathing, it should be, (were it not for its sanitary reputation, it inevitably would be,) one vast residence-park. Except on its extreme northern end, and along its higher ridges, it has,—and, unfortunately, it deserves,—a most unenviable reputation for insalubrity. Here and there, on the southern slope also, there are favored places which are unaccountably free from the pest, but, as a rule, it is, during the summer and autumn, unsafe to live there without having constant recourse to preventive medication, or exercising unusual and inconvenient precautions with regard to exposure to mid-day sun and evening dew. There are always to be found attractive residences, which are deserted by their owners, and are offered for sale at absurdly low prices. There are isolated instances of very thorough and very costly draining, which has failed of effect, because so extensive a malarial region cannot be reclaimed by anything short of a systematic improvement of the whole.

It has been estimated that the thorough drainage of the low lands, valleys and ponds of the eastern end of the island, including two miles of the south shore, would at once add $5,000,000 to the market value of the real estate of that section. There can be no question that any radical improvement in this respect would remove the only obstacle to the rapid settlement of the island by those who wish to live in the country, yet need to be near to the business portion of the city. The hope of such improvement being made, however, seems as remote as ever,—although any one at all acquainted with the sources of miasm, in country neighborhoods, can readily see the cause of the difficulty, and the means for its removal are as plainly suggested.

Staten Island is, by no means, alone in this respect. All who know the history of the settlement of the other suburbs of New York are very well aware that those places which are free from fever-and-ague and malarial neuralgia, are extremely rare.

The exact cause of fever-and-ague and other malarial diseases is unknown, but it is demonstrated that, whatever the cause is, it is originated under a combination of circumstances, one of which is undue moisture in the soil. It is not necessary that land should be absolutely marshy to produce the miasm, for this often arises on cold, springy uplands which are quite free from deposits of muck. Thus far, the attention of scientific investigators, given to the consideration of the origin of malarial diseases, has failed to discover any well established facts concerning it; but there have been developed certain theories, which seem to be sustained by such knowledge as exists on the subject.

Dr. Bartlett, in his work on the Fevers of the United States, says:—"The essential, efficient, producing cause of periodical fever,—the poison whose action on the system gives rise to the disease,—is a substance or agent which has received the names of malaria, or marsh miasm. The nature and composition of this poison are wholly unknown to us. Like most other analogous agents, like the contagious principle of small-pox and of typhus, and like the epidemic poison of scarletina and cholera, they are too subtle to be recognized by any of our senses, they are too fugitive to be caught by any of our contrivances.

"As always happens in such cases and under similar circumstances, in the absence of positive knowledge, we have been abundantly supplied with conjecture and speculation; what observation has failed to discover, hypothesis has endeavored and professed to supply. It is quite unnecessary even to enumerate the different substances to which malaria has been referred. Amongst them are all of the chemical products and compounds possible in wet and marshy localities; moisture alone; the products of animal and vegetable decomposition; and invisible living organisms. * * * * Inscrutable, however, as the intimate nature of the substances or agents may be, there are some few of its laws and relations which are very well ascertained. One of these consists in its connection with low, or wet, or marshy localities. This connection is not invariable and exclusive, that is, there are marshy localities which are not malarious, and there are malarious localities which are not marshy; but there is no doubt whatever that it generally exists."

In a report to the United States Sanitary Commission, Dr. Metcalfe states, that all hypotheses, even the most plausible, are entirely unsupported by positive knowledge, and he says:—

"This confession of ignorance still leaves us in possession of certain knowledge concerning malaria, from which much practical good may be derived.

"1st. It affects, by preference, low and moist localities.

"2d. It is almost never developed at a lower temperature than 60° Fahrenheit.

"3d. Its evolution or active agency is checked by a temperature of 32°.

"4th. It is most abundant and most virulent as we approach the equator and the sea-coast.

"5th. It has an affinity for dense foliage, which has the power of accumulating it, when lying in the course of winds blowing from malarious localities.

"6th. Forests, or even woods, have the power of obstructing and preventing its transmission, under these circumstances.

"7th. By atmospheric currents it is capable of being transported to considerable distances—probably as far as five miles.

"8th. It may be developed, in previously healthy places, by turning up the soil; as in making excavations for foundations of houses, tracks for railroads, and beds for canals.

"9th. In certain cases it seems to be attracted and absorbed by bodies of water lying in the course of such winds as waft it from the miasmatic source.

"10th. Experience alone can enable us to decide as to the presence or absence of malaria, in any given locality.

"11th. In proportion as countries, previously malarious, are cleared up and thickly settled, periodical fevers disappear—in many instances to be replaced by the typhoid or typhus."

La Roche, in a carefully prepared treatise on "Pneumonia; its Supposed Connection with Autumnal Fevers," recites various theories concerning the mode of action of marsh miasm, and finds them insufficient to account for the phenomena which they produce. He continues as follows:—

"All the above hypotheses failing to account for the effects in question, we are naturally led to the admission that they are produced by the morbific influence of some special agent; and when we take into consideration all the circumstances attending the appearance of febrile diseases, the circumscribed sphere of their prevalence, the suddenness of their attack, the character of their phenomena, etc., we may safely say that there is nothing left but to attribute them to the action of some poison dissolved or suspended in the air of the infected locality; which poison, while doubtless requiring for its development and dissemination a certain degree of heat, and terrestrial and atmospheric moisture, a certain amount of nightly condensation after evaporation, and the presence of fermenting or decomposing materials, cannot be produced by either of these agencies alone, and though indicated by the chemist, betrays its presence by producing on those exposed to its influence the peculiar morbid changes characterizing fever."

He quotes the following from the Researches of Dr. Chadwick:—

"In considering the circumstances external to the residence, which affect the sanitary condition of the population, the importance of a general land-drainage is developed by the inquiries as to the cause of the prevalent diseases, to be of a magnitude of which no conception had been formed at the commencement of the investigation. Its importance is manifested by the severe consequences of its neglect in every part of the country, as well as by its advantages in the increasing salubrity and productiveness wherever the drainage has been skillful and effectual."

The branch of the Art of Drainage which relates to the removal of the fecal and other refuse wastes of the population of towns, is quite different from that which has been described in the preceding pages, as applicable to the agricultural and sanitary improvement of lands under cultivation, and of suburban districts. Still, the fact that town and house drainage affords a means for the preservation of valuable manures, justifies its discussion in an agricultural work, and "draining for health" would stop far short of completeness were no attention paid to the removal of the cause of diseases, which are far more fatal than those that originate in an undrained condition of the soil.

The extent to which these diseases, (of which typhoid fever is a type,) are prevented by sanitary drainage, is strikingly shown in the extract which commences this chapter. Since the experience to which this report refers, it has been found that the most fatal epidemics of the lower portions of London originated in the choked condition of the street sewers, whose general character, as well as the plan of improvement adopted are described in the following "Extracts from the Report of the Metropolitan Board of Works," made in 1866.

"The main sewers discharged their whole contents direct into the Thames, the majority of them capable of being emptied only at the time of low water; consequently, as the tide rose, the outlets of the sewers were closed, and the sewage was dammed back, and became stagnant; the sewage and impure waters were also constantly flowing from the higher grounds, in some instances during 18 out of the 24 hours, and thus the thick and heavy substances were deposited, which had to be afterwards removed by the costly process of hand labor. During long continued or copious falls of rain, more particularly when these occurred at the time of high water in the river, the closed outlets not having sufficient storage capacity to receive the increased volume of sewage, the houses and premises in the low lying districts, especially on the south side of the river, became flooded by the sewage rising through the house drains, and so continued until the tide had receded sufficiently to afford a vent for the pent-up waters, when the sewage flowed and deposited itself along the banks of the river, evolving gases of a foul and offensive character.

"This state of things had a most injurious effect upon the condition of the Thames; for not only was the sewage carried up the river by the rising tide, at a time when the volume of pure water was at its minimum, and quite insufficient to dilute and disinfect it, but it was brought back again into the heart of the metropolis, there to mix with each day's fresh supply, until the gradual progress towards the sea of many day's accumulation could be plainly discerned; the result being that the portion of the river within the metropolitan district became scarcely less impure and offensive than the foulest of the sewers themselves. * * * * * *

"The Board, by the system they have adopted, have sought to abolish the evils which hitherto existed, by constructing new lines of sewers, laid in a direction at right angles to that of the existing sewers, and a little below their levels, so as to intercept their contents and convey them to an outfall, on the north side of the Thames about 11-1/4 miles, and on the south side about 14 miles, below London Bridge. By this arrangement as large a proportion of the sewage as practicable is carried away by gravitation, and a constant discharge for the remainder is provided by means of pumping. At the outlets, the sewage is delivered into reservoirs situate on the banks of the Thames, and placed at such levels as enable them to discharge into the river at or about the time of high water. The sewage thus becomes not only at once diluted by the large volume of water in the river at the time of high water, but is also carried by the ebb 26 miles below London Bridge, and its return by the following flood-tide within the metropolitan area, is effectually prevented."

The details of this stupendous enterprise are of sufficient interest to justify the introduction here of the "General Statistics of the Works" as reported by the Board.

"A few statistics relative to the works may not prove uninteresting. The first portion of the works was commenced in January 1859, being about five months after the passing of the Act authorising their execution. There are 82 miles of main intercepting sewers in London. In the construction of the works 318,000,000 of bricks, and 880,000 cubic yards of concrete have been used, and 3,500,000 cubic yards of earth excavated. The cost, when completed, will have been about £4,200,000. The total pumping power employed is 2,300 nominal horse power: and if the engines were at full work, night and day, 44,000 tons of coals per annum would be used; but the average consumption is estimated at 20,000 tons. The sewage to be intercepted by the works on the north side of the river, at present amounts to 10,000,000 cubic feet, and on the south side 4,000,000 cubic feet per day; but provision is made for an anticipated increase in these quantities, in addition to the rainfall, amounting to a total of 63,000,000 cubic feet per day, which is equal to a lake of 482 acres, three feet deep, or 15 times as large as the Serpentine in Hyde Park."

A very large portion of the sewage has to be lifted thirty-six feet to the outfall sewer. The works on the north side of the Thames were formally opened, by the Prince of Wales, in April 1865.

In the hope that the immense amount of sewage, for which an escape has been thus provided, might be profitably employed in agriculture, advertisements were inserted in the public journals asking for proposals for carrying out such a scheme; and arrangements were subsequently made for an extension of the works, by private enterprise, by the construction of a culvert nine and a half feet in diameter, and forty miles in length, capable of carrying 12,000,000 cubic feet of sewage per day to the barren sands on the coast of Essex; the intention being to dispose of the liquid to farmers along the line, and to use the surplus for the fertilization of 7000 acres, (to be subsequently increased,) which are to be reclaimed from the sea by embankments and valve sluice-gates.

The estimated cost of this enterprise is about $10,000,000.

The work which has been done, and which is now in contemplation, in England, is suggestive of what might, with advantage, be adopted in the larger cities in America. Especially in New York an improved means of outlet is desirable, and it is doubtful whether the high rate of mortality of that city will be materially reduced before effective measures are devised for removing the vast accumulations of filth, which ebb and flow in many of the larger sewers, with each change of the tide; and which are deposited between the piers along the river-sides.

It would be practicable to construct a main receiving sewer under the river streets, skirting the city, from the vicinity of Bellevue Hospital on the east side, passing near the outer edge of the Battery, and continuing to the high land near 60th street on the west side; having its water level at least twenty feet below the level of the street, and receiving all of the sewage which now flows into the river. At the Battery, this receiving sewer might be connected, by a tunnel, with the Brooklyn shore, its contents being carried to a convenient point south of Fort Hamilton,—where their discharge, (by lifting steam pumps), into the waters of the Lower Bay, would be attended with no inconvenience. The improvement being carried out to this point, it would probably not be long before the advantages to result from the application of the sewage to the sandy soil on the south side of Long Island would be manifest.