=Pail type.=--A very serviceable pail privy is shown in figures 8 and 9.
The method of ventilation is an adaptation of a system that has proved
very effective in barns and other buildings here and abroad. A flue
with a clear opening of 16 square inches rises from the rear of the seat
and terminates above the ridge-pole in a cowl or small roofed housing.
Attached to this flue is a short auxiliary duct, 4 by 15 inches, for
removing foul air from the top of the privy. In its upper portion on the
long sides the cowl is open, allowing free movement of air across the top
of the flue. In addition the long sides of the cowl are open below next to
the roof. These two openings, with the connecting vertical air passages,
permit free upward movement of air through the cowl, as indicated by the
arrows. The combined effect is to create draft from beneath the seat
and from the top of the privy. The ventilating flue is 2 by 8 inches at
the seat and 4 by 4 inches 5 feet above. The taper slightly increases the
labor of making the flue, but permits a 2-inch reduction in the length of
the building.
[Illustration: Fig. 8.--Pail privy. Well constructed, ventilated, and
screened. With proper care is sanitary and unobjectionable.]
[Illustration: Fig. 9.--Full privy.]
In plan the privy is 4 by 4-1/2 feet. The sills are secured to durable
posts set about 4 feet in the ground. The boarding is tight, and all vents
and windows are screened to exclude insects. The screens may be the same
as for pit privies or, if a more lasting material is desired, bronze or
copper screening of 14 squares to the inch may be used. The entire seat
is hinged, thus permitting removal of the receptacle and facilitating
cleaning and washing the underside of the seat and the destruction of
spiders and other insects which thrive in dark, unclean places. The
receptacle is a heavy galvanized-iron garbage can. Heavy brown-paper bags
for lining the can may be had at slight cost, and their use helps to keep
the can clean and facilitates emptying. Painting with black asphaltum
serves a similar purpose and protects the can from rust. If the contents
are frozen, a little heat releases them. Of nonfreezing mixtures a strong
brine made with common salt or calcium chloride is effective. Two and
one-half to 3 pounds of either thoroughly dissolved in a gallon of water
lowers the freezing point of the mixture to about zero. Denatured alcohol
or wood alcohol in a 25 per cent solution has a like low freezing point
and the additional merit of being noncorrosive of metals. The can should
be emptied frequently and the contents completely buried in a thin layer
by a plow or in a shallow hand-dug trench at a point below and remote from
wells and springs. Wherever intestinal disease exists the contents of
the can should be destroyed by burning or made sterile before burial by
boiling or by incorporation with a strong chemical disinfectant.
[Illustration: BPR-RE 1382