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ity as soon as they become full. This secures the thorough periodical flushing of the lower line of the drain, and allows us to use very low gradients where a slight fall is made necessary by the level of the land. Field's flushing tank is not only valuable for this use, but equally so for the accumulating of the drainage of single houses, and for discharging it with a cleansing flow from the house-drain; and enables us to use with safety, for any private house, an outlet drain only four inches in diameter.

For the ultimate disposal of the drainage of country or village houses, of asylums and even of small towns, the delivery of the flushing tanks by periodical discharge into common agricultural drain tiles two inches in diameter, laid on lines two to six feet apart, having a fall of not more than four inches per hundred feet, with uncemented joints, and placed not more than 8 or 10 inches below the surface of the ground, secures the absorption of the liquid by the upper portion of the soil, within reach of the roots of plants, and of the oxidizing influence of the air. This constitutes the most efficient means of disposal yet devised. I have had this system in operation at my own house since 1870, and find it entirely satisfactory. In 1876, I adopted it for the disposal of the entire sewage of the village of Lenox, Mass., and I do not hesitate to recommend it as satisfactory in all similar cases.

SUPPLEMENTAL CHAPTERS.

The directions for work, as originally given in Chapter IV, should be followed only as modified by the later information given below; which is a reprint of two articles published in the American Agriculturist, after the body of this work was written.

CHAPTER XII.

IMPROVEMENTS IN DRAINING TILES.

In view of the fact that in my article on "Tile-Draining," published in the Agricultural Annual, and in my first edition of "Draining for Profit and Draining

Figs. 50 and 51.—TILE AND COLLAR.

for Health," I have very strenuously insisted upon the necessity for using silt-basins in the laying of underdrains, I have thought it advisable to state explicitly the reasons which have led me, in my own practice and in advice to others, to dispense almost entirely with their use. They were at best a rather imperfect and quite ex

pensive means for preventing the obstruction of drains by accumulations of silt; but, with the draining materials procurable at the time when the book and article above alluded to were written, they were indispensable. During the last year I have used largely the tiles manufactured by Messrs. C. W. Boynton & Co., of Woodbridge, N. J., which are made with certain modifications and improvements that very greatly lessen the necessity for siltbasins. Indeed, in draining my own farm of 60 acres, I

Fig. 52.-LINE OF TILES WITH COLLARS AS LAID.

have not made a single one of these. The tiles referred to are made from the tenacious clay of the Amboy region, which is so much richer in quality and so much more uniform than the brick clay ordinarily employed for the purpose, that it is found easy to make even the smallest tiles two feet long, which, of itself, is a great advantage, inasmuch as it reduces by one-half the number of joints, which must always form a greater or less obstacle to the smooth flow of water, while there are still openings enough remaining for the complete admission of soil

Fig. 53. CURVED TILES. Fig. 54.

water. Only round tiles are made at this establishment, the

smaller ones being provided with wellfitting collars for

connecting their ends. The tile and collar respectively are shown in figs. 50 and 51. The continuous line is laid as shown in fig. 52. The curved tiles, such as those shown in figs. 53 and 54, bent to various degrees, in order to suit the requirements of different circumstances, I have found of great assistance, especially in abruptly changing the direction of main drains. Figure 55 represents an enlarging tile, by which, in increasing the

size of a drain, as from two to three inches, the abrupt rough edge, formed by inserting the smaller tile into the larger one, may be avoided. This gradual enlargement will effectually prevent the checking of the flow that is unavoidable in all cases where a confined stream breaks abruptly into a larger conduit. The most important improvement that Boynton has made, and the one which does more than any other to obviate the need for siltbasins, is the junction piece, shown in fig. 56, which is used for connecting lateral drains with mains, or one main with another. These junction

Fig. 55.

[graphic]

pieces are made complete, as shown in the figure, for all the different sizes of mains and laterals; and, by their use, the water from the lateral is introduced into the main at an angle of 45°. As it enters near the bottom of the main, it materially accelerates the flow in the latter by its force of entry, while, with the best joint that it was formerly possible for us to make by the aid of the tile pick, there was an

Fig. 56.

JUNCTION-PIECE.

Fig. 57.-CONNECTION OF LATERAL WITH MAIN.

interruption of the flow and frequently a tendency to deposit silt at the junctions. By the use of these junction pieces, the points of intersection are made the safest of

the whole drain, instead of being, as they were under the old system, the most insecure. The manner in which the collared small lateral is connected with the lower part of

Fig. 58.

the larger tile of the main drain is shown in fig. 57. When the lateral approaches

the main at a right angle, or

at a very obtuse angle, the curved tile shown in fig. 54, should be used, in order that the flow may strike in the direction of the oblique junction.

Boynton & Co. have also made an earthern-ware grating for covering outlets,

[graphic]

which is very much cheaper than the wire grating recommended in Chapter IV; and, as the last pipe of the drain is glazed or vitrified ware, the outer end may project a little beyond the mason-work with

Fig. 59.-VIEW OF OUTLET.

The

out fear that it will be injured by frost. This grated outlet is shown in fig. 58. The grating is movable, and can easily be detached for cleaning when necessary. appearance of an outlet, so arranged in connection with masonry, is shown in fig. 59, and it is difficult to conceive of any plan more simple or more effective.

NOTE.-(Third edition.) In connection with the sewerage of towns where agricultural drain tiles are frequently used in the same trenches with the sewer pipes, I have devised-and have patented-a very simple method of jointing tiles with strips of muslin as a substitute for collars. These muslin collars are not only cheaper than earthenware collars, but they hug the tiles so closely that no water can enter them until it has been strained, and they maintain their usefulness until after the earth has become so compacted that the need for any collars has passed.

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