"clays, will get down 4 feet with a 12-inch opening, orde "narily; if he wishes to show off, he will sacrifice his ' own comfort to appearance, and will do it with a 10-inch "opening."

In the Central Park work, sets of these tools were pro cured, at considerable expense, and every effort was made to compel the men to use them, but it was soon found that, even in the easiest digging, there was a real economy in using, for the first 3 feet of the ditch, the common spade, pick, and shovel,-finishing the bottoms with the narrow spade and scoop hereafter described, and it is probable that the experience of that work will be sustained by that of the country at large.

Marking the Lines.-To lay a drain directly under the Dosition of its stakes, would require that enough earth be eft at each point to hold the stake, and that the ditch be tunneled under it. This is expensive and unnecessary. It is better to dig the ditches at one side of the lines of stakes, far enough away for the earth to hold them firmly in their places, but near enough to allow measurements to be taken from the grade pegs. If the ditch be placed always to the right, or always to the left, of the line, and at a uniform distance, the general plan will remain the same, and the lines will be near enough to those marked on the map to be easily found at any future time. In fact, if it be known that the line of tiles is two feet to the right of the position indicated, it will only be necessary, at any time, should it be desired to open an old drain, to measure two feet to the right of the surveyed position to strike the line at once.

In soils of ordinary tenacity, ditches 4 feet deep need not be more than twenty (20) inches wide at the surface, and four (4) inches wide at the bottom. This will allow, in each side, a slope of eight (8) inches, which is sufficient except in very loose soils, and even these may be braced if inclined to cave in. There are cases where the soil

up,

contains so much running sand, and is so saturated with water, that no precautions will avail to keep up the banks. Ditches in such ground will sometimes fall in, until the excavation reaches a width of 8 or 10 feet. Such instances, however, are very rare, and must be treated as the occa sion suggests.

One of the garden lines should be set at a distance or about 6 inches from the row of stakes, and the other at a further distance of 20 inches. If the land is in grass, the position of these lines may be marked with a spade, and they may be removed at once; but, if it is arable land, it will be best to leave the lines in position until the ditch is excavated to a sufficient depth to mark it clearly. Indeed, it will be well at once to remove all of the sod and surface soil, say to a depth of 6 inches, (throwing this on the same side with the stakes, and back of them.) The whole force can be profitably employed in this work, until all of the ditches to be dug are scored to this depth over the entire tract to be drained, except in swamps which are still too wet for this work.

Water Courses.-The brooks which carry the water from the springs should be "jumped" in marking out the lines, as it is desirable that their water be kept in separate channels, so far as possible, until the tiles are ready to receive it, as, if allowed to run in the open ditches, it would undermine the banks and keep the bottom too soft for sound work.

With this object, commence at the southern boundary of our example tract, 10 or 15 feet east of the point of outlet, and drive a straight, temporary, shallow ditch to a point a little west of the intersection of the main line D with its first lateral; then carry it in a northwesterly direction, crossing C midway between the silt-basin and stake C1, and thence into the present line of the brook, turning all of the water into the ditch. A branch of this

ditch may be run up between the lines Fand G to receive the water from the spring which lies in that direction. This arrangement will keep the water out of the way until the drains are ready to take it.

The Outlet. The water being all discharged through the new temporary ditch, the old brook, beyond the boundary, should be cleared out to the final level (3.75,) and an excavation made, just within the boundary, sufficient to receive the masonry which is to protect the outlet. A good form of outlet is shown in Fig. 23. It may

Fig. 23.-OUTLET, SECURED WITH MASONRY AND GRATING. be cheaply made by any farmer, especially if he have good stone at hand;-if not, brick may be used, laid on a solid foundation of stout planks, which, (being protected from the air and always saturated with water,) will last a very long time.

If made of stone, a solid floor, at least 2 feet square, should be placed at, or below, the level of the brook. If this consist of a single stone, it will be better than if of several smaller pieces. On this, place another layer extending the whole width of the first, but reaching only from its inner edge to its center line, so as to leave a foot

in width of the bottom stone to receive the fall of the water. This second layer should reach exactly the grade of the outlet (3.50) or a height of 3 inches from the brook level. On the floor thus made, there should be laid the tiles which are to constitute the outlets of the several drains; i. e., one 3-inch tile for the line from the siltbasin, two 14-inch for the lines F and G, and one 24-inch for the main line E. These tiles should lie close to each other and be firmly cemented together, so that no water can pass outside of them, and a rubble-work of stone may with advantage be carried up a foot above them. Stone work, which may be rough and uncemented, but should always be solid, may then be built up at the sides, and covered with a secure coping of stone. A floor and sloping sides of stone work, jointed with the previously described work, and well cemented, or laid in strong clay or mortar, may, with benefit, be carried a few feet beyond the outlet. This will effectually prevent the undermining of the structure. After the entire drainage of the field is finished, the earth above these sloping sides, and that back of the coping, should be neatly sloped, and protected by sods. An iron grating, fine enough to prevent the entrance of vermin, placed in front of the tile, at a little distance from them, and secured by a flat stone set on edge and hollowed out, so as merely to allow the water to flow freely from the drains,—the stone being cemented in its place so as to allow no water to pass under it,-will give a substantial and permanent finish to the structure.

An outlet finished in this way, at an extra cost of a few dollars, will be most satisfactory, as a lasting means of securing the weakest and most important part of the sys tem of drains. When no precaution of this sort is taken, the water frequently forces a passage under the tile for some distance up the drains, undermining and displacing them, and so softening the bottom that it will be difficult, in making repairs, to secure a solid foundation for the work.

Usually, repairs of this sort, aside from the annoyance at tending them, will cost more than the amount required to make the permanent outlet described above. As well con structed outlets are necessarily rather expensive, as much of the land as possible should be drained to each one that it is necessary to make, by laying main lines which will collect all of the water which can be brought to it.

The Main Silt-Basin.-The silt-basin, at which the drains are collected, may best be built before any drains are brought to it, and the work may proceed simultane ously with that at the outlet. It should be so placed that its center will lie exactly under the proposed line of the drain, because it will constitute one of the leading landmarks for the survey.*

Before removing the stake and grade stake, mark their position by four stakes, set at a distance from it of 4 or 5 feet, in such positions that two lines, drawn from those which are opposite to each other, will intersect at the point indicated; and place near one of them a grade stake, driven to the exact level of the one to be removed. This being done, dig a well, 4 feet in diameter, to a depth of 24 feet below the grade of the outlet drain, (in the exam. ple under consideration this would be 5 feet below the grade stake.) If much water collects in the hole, widen it, in the direction of the outlet drain, sufficiently to give room for baling out the water. Now build, in this well, a structure 2 feet in interior diameter, such as is shown in Fig. 24, having its bottom 2 feet, in the clear, below the grade of the outlet, and carry its wall a little higher than the general surface of the ground. At the proper height insert, in the brick work, the necessary tiles for all incom ing and outgoing drains; in this case, a 3-inch tile for

The drains, which are removed a little to one side of the lines of stakes, should strike the center of the silt-basin.