liquid they may contain; the tiles being laid
either with collars around the joints, or with bits of paper laid over
them, to prevent the rattling in of loose earth during the filling. The
excavated earth is to be returned to its place, well compacted, and
covered with its sod. Suppose this drain to have a cross-section equal
to three square inches, and a length of one hundred feet, its capacity
will equal about sixteen gallons, or a half-barrel. If this amount of
liquid be rapidly discharged into the drain, the inclination being
slight, it will at once be filled or nearly filled for its whole length,
and the liquid will leak away in tolerably uniform proportion at every
joint along the line, and will saturate the surrounding earth. The plan
adopted at Lenox, and recommended for all small villages which cannot
secure a better outlet, is simply a multiplication of these drains to a
sufficient extent.

A description of the manner in which the Lenox work is arranged will
illustrate the adaptation of the system to its circumstances. As
circumstances vary, the adaptation must be modified. (See Figure 8.)

[Illustration: FIG. 8.--DIAGRAM ILLUSTRATING MANNER OF SEWAGE DISPOSAL
AT LENOX, MASS.]

The main outlet sewer delivers at a distance of about one-half mile from
the last junction with a branch sewer. It is a six-inch pipe five feet
below the surface of the ground, and it delivers into a flush-tank like
that shown in Figure 6, but having a capacity of about five hundred
cubic feet. This tank stands at the upper side of a field having an
inclination of seven in one hundred. There is a branch from the main
sewer, above the tank, supplied with a stop-cock, by which, in case of
need, the sewage may be carried on down the hill without going into
the tank. The outlet from the chamber below the siphon leads off in
another direction down the hill, and has a stop-cock and a branch which
will allow its flow to be diverted. The discharge of this diverted
stream and the discharge through the branch of the main above the tank,
both deliver into a horizontal surface gutter to be well grassed, and
lying at the top of the land to be irrigated. By this arrangement,
should repairs become necessary in the tank, the flow may be turned into
the gutter; or, should it be desired for any reason to use the outflow
of the tank for surface irrigation, the second branch outlet will
deliver it into the same gutter, where, the outflow being uniform al