_(To the Editor of the Mirror.)_

[Illustration:
A A. The Pot.
B B. The Triangular Board.
C. The Cover.
D. Vessel to receive the Filtered Water.
E. Dotted Line, showing the Proportion of
Charcoal and Sand.]

Herewith I send you an outline drawing of an economical filtering
apparatus, suitable for the use of any dwelling. Its construction is
perfectly simple, and at the cost of a few shillings in its
erection. The pot consists of an unglazed inverted vessel,
manufactured at potteries for the use of sugar-bakers, and placed
through a hole in a triangular board, resting upon two ledges,
occupying a corner in a kitchen or any other apartment. In the
inside of the pot a bushel of the whitest sand is to be introduced;
which sand, after being washed in a clean tub with about three
changes of water, to dissolve and clear away the clayey matter, is
to be mixed with half a peck of finely-bruised charcoal. This will
fill about one-third of the pot; but before the sand is placed in
the vessel, the small hole at the bottom of the pot should have an
oyster-shell placed over it, with the convex side uppermost, to
prevent the sand washing through. This filters foul water perfectly
pellucid and clear very quickly, as I have seen its effects for
years with the most perfect success. When the sand becomes foul by
time, it can be taken out and washed, or fresh materials can be
repeated; great care should be observed not to put more water in the