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CHAPTER IV.

HOW TO MAKE THE DRAINS.*

Knowing, now, precisely what is to be done; having the lines all staked out, and the stakes so marked as to be clearly designated; knowing the precise depth at which the drain is to be laid, at every point; having the requisite tiles on the ground, and thoroughly inspected, the operator is prepared to commence actual work.

He should determine how many men he will employ, and what tools they will require to work to advantage. It may be best that the work be done by two or three men, or it may be advisable to employ as many as can work without interfering with each other. In most cases,— especially where there is much water to contend with,—the latter course will be the most economical, as the ditches will not be so liable to be injured by the softening of their bottoms, and the caving in of their sides.

The Tools Required are a subsoil plow, two garden lines, spades, shovels, and picks; narrow finishing spades, a finishing scoop, a tile pick, a scraper for filling the ditches, a heavy wooden maul for compacting the bottom filling, half a dozen boning-rods, a measuring rod, and a plumb rod. These should all be on hand at the outset, so that no delay in the work may result from the want ol them.

Writers on drainage, almost without exception, recommend the use of elaborate sets of tools which are intended

* The instructions given in this Chapter are somewhat modified by newer processes, which are described in the Supplemental Chapters, especially Chapter XJIJ. These should be well noted.—{Note to %d edition.)

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foi cutting very narrow ditches,—only wide enough at the bottom to admit the tile, and not allowing the workmen to stand in the bottom of the ditch. A set of these tools is shown in Fig. 22.

Possibly there may be soils in which these implements, in the hands of men skilled in their use, could be employed with economy, but they are very rare, and it is not believed to be possible with unskilled laborers to regulate the bottom of the ditch so accurately as is advisable, unless the workman can stand directly upon it, cutting it more smoothly than he could if the point of his tool were a foot or more below the level on which he stands.

On this subject, Mr. J. Bailey Denton, one of the first draining engineers of Great Britain, in a letter to Judge French, says:

"As to tools, it is the same with them as it is with the "art of draining itself,—too much rule and too much draw"ing upon paper; all very right to begin with, but very "prejudicial to progress. I employ, as engineer to the "General Land Drainage Company, and on my private "account, during the drainage season, as many as 2,000 "men, and it is an actual fact, that not one of them uses "the set of tools figured in print. I have frequently pur"chased a number of sets of the Birmingham tools, and "sent them down on extensive works. The laborers would "purchase a few of the smaller tools, such as Nos. 290, "291, and 301, figured in Morton's excellent Cyclopaedia "of Agriculture, and would try them, and then order "others of the country blacksmith, differing in several "respects; less weighty and much less costly, and more "over, much better as working tools. All I require of the "cutters, is, that the bottom of the drain should be evenly "cut, to fit the size of the pipe. The rest of the work "takes care of itself; for a good workman will economize "his labor for his own sake, by moving as little earth as "practicable; thus, for instance, a first-class cotter, in "clays, will get down 4 feet with a 12-inch opening, ord* M narily; if he wishes to show off, he will sacrifice hii 'own comfort to appearance, and will do it with a 10-inch "opening." •

In the Central Park work, sets of these tools were procured, 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.

Narking the Lines.—To lay a drain directly under the position 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 ap, if inclined to cave in. There are cases where the soil 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 occasion suggests.

One of the garden lines should be set at a distance ot 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 C 1, and thence into the present line of the brook, turning all of the water into the ditch. A branch of thu

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