ground, against cattle, etc., by a strong cover, as represented. This arrangement will furnish ample means for investigating drains, convincing the incredulous, and also, of making observations on the working of the system in different portions of the work.

We have before spoken of sinks or silt-basins. These should not be confounded with "peep-holes." The accompanying cut gives a very good idea of

their construction. They should be built of solid masonry, large enough to admit of being cleaned out without inconvenience. A relief-pipe, as shown in the figure, will not always be necessary, and may give rise to some inconvenience.

Lid

The chain, which is attached to the flap covering the incoming drain, is operated from above. The object of this flap or valve is to prevent the water from flowing through the drain for any desirable length of time. The pent up water, when released, rushes down with force, sufficient to carry down the sand and other impediments from the tiles above, also effecting a partial cleansing of the basin itself. The lid, Fig. 46, should be made of cast iron, and firmly fixed, to prevent displacements and accidents.

Fig. 46.

Large Outlet.-No portion of the whole drain requires to be more substantially constructed than the large outlet; and none is more likely to be neglected. The drains we expect to last a lifetime, and certainly the outlet, which is the foundation and abutment of the whole, should be built with the same expectation. We have before spoken of the outlets of the minor drains, where they are emptied into the open or main ditch. We have now to speak of a preferable plan, namely, where the minor drains are united, forming a sub-main, and of the outlet which this sub-main should have. On this subject Mr. Denton says:

"Too many outlets are objectionable, on account of the labor of their maintenance; too few are objectionable, because they can only exist where there are mains of excessive length. A limit of twenty acres to an outlet, resulting in an average of, perhaps, fourteen acres, will appear, by the practices of the best drainers, to be about the proper thing. If a shilling an acre is reserved for fix. ing the outlets, which should be iron pipes with swing gratings, in masonry, very substantial work may be done."

Earthenwar
Pina

Slone

FIG. 47.

We present, in Fig. 47, a section of such outlet as has been found to answer its purpose effectually. It is composed of solid masonry, strongly braced. The exit pipe is of cast iron, projecting a few inches from the work. The exit should be some inches, or even a foot and a half, if that distance can be had, from the bottom of the main drain, bo'h that the water may flow off readily, and that it may be protected 'rom any backwaters ascending the main drain from the stream or pond in which it flows. It would be still better, if a fall could be given to the main drain b fore discharging its water into the creek or pond, thus preventing any back water whatever.

CHAPTER X.

DRAINING TOOLS, INSTRUMENTS, ETC.

The instruments used in the construction of drains are simple and few in number. They consist, mainly, of shovels, such as are used for ordinary purposes, spades, scoops, and picks. In addition to these, a pipe-layer will be necessary, for narrow drains, and a drain gauge and level are very convenient, if not necessary. Some of these tools are not made in this country, at present; they must either be imported, or some substitute obtained of an ingenious blacksmith.

Shovels.-Ordinary shovels will be very useful in removing the earth, when the ditch is not less than one foot in width. They should be made of the best material and strongly braced by two slips of iron, extending some distance up the handle from the socket. The long-handled, pointed, scoop shovel, in common use on our railroads, will be found very useful in removing light soil or gravel, after being turned up with the pick.

Spades.-Three spades are all that are necessary. These should be of different sizes, gradually diminishing in width, to suit different depths. When the ground contains stones, or other impediments, they should be made perfectly flat, as in Figs. 48, 49, and 50. When the soil is free from all impediments, a curved form, represented in Fig. 52, (next page,) will be found advantageous.

Morton, in the Cyclopædia of Agriculture, gives the spades, Figs. 50, 51, and 53, as those most in general use, for digging the last, or lowest portions of the drain.

Fig. 52 represents a broad and curved shovel, somewhat triangular in shape, with a bent handle. This is used for removing dirt from large drains.

FIG. 52.

FIG. 53.

FIG. 54.

FIG. 55.

Scoops.-For removing the soil from the bottom, and shaping out the ditch for the reception of the tile, scoops are necessary. For small and narrow ditches,

different forms are used, as shown in Figs. 56 and 59. These are to be used standing n the surface of the ground. The instrument shown in Fig. 59, is especially adapted to fitting the bottom for round tiles or pipes.

When the ditches are made with flat bottoms, such a tool as represented by Fig.

57 is used for scooping it out. When the bottom is soft, or the crumbs mixed with water, a similar tool, with the sides turned up, as represented by Fig. 58, is used to clean out the ditch.

Picks. Where the subsoil is stony, or hard-pan, a pick will be necessary to loosen it. The dirt is then removed with the long scoop shovel. The common pick (Figs.

60 and 61) is all that is necessary for this purpose, though, in some cases, a foot pick (Fig. 2) may be advantageously used.

Pickaxes may be made either heavy or light, as suits the workman. They should be strongly made, and the usual form, with a pick at one end and chisel at the other, is best.

Pipe layer is a convenient tool; the handle is long and light, like that of a rake; from the end of this passes a stout piece of iron wire or rod, a foot in length, and having a direction almost at right angles with the handle. This is for the purpose of laying the tiles or pipes into the drain; and, if the drains are made as narrow as they ought to be, it will then be not only convenient, but highly useful. It is better un sond by reference to the cut (Fig. 63) than from description.