Such pits can be
built in or attached to the stable so that manure can be easily thrown
in at the time of cleaning and so constructed that the manure can be
readily removed. It is desirable that the manure be placed in these
fly-proof receptacles as soon as possible after it is voided. The
essential point is that flies be prevented from reaching the manure, and
for this reason the pit or bin must be tightly constructed, preferably
of concrete, and the lid kept closed except when the manure is being
thrown in or removed. The difficulty has been that manure often becomes
infested before it is put into the container, and flies frequently breed
out before it is emptied and often escape through the cracks. To obviate
these difficulties a manure box or pit with a modified tent trap or cone
trap attached is desirable.

In order to retain the fertilizing value of manure to the greatest
extent it is advisable that air be excluded from it as much as possible
and that it be protected from the leaching action of rains. This being
the case, there is really no necessity for covering a large portion of
the top of the box with a trap, but merely to have holes large enough to
attract flies to the light, and to cover these holes with ordinary
conical traps, with the legs cut off, so, that the bottoms of the traps
will fit closely to the box. The same arrangement can be made where
manure is kept in a pit. If manure boxes or pits are kept fly tight they
are satisfactory under farm or dairy conditions for the storage of
manure during the busy season when it can not be hauled out daily.

FREQUENCY WITH WHICH MANURE SHOULD BE REMOVED IN CITIES AND TOWNS.

In deciding the question as to how often manure should be removed in
cities and towns, it should be borne in mind that when the larvae have
finished feeding they will often leave the manure and pupate in the
ground below or crawl some distance away to pupate in debris under
boards or stones and the like. Hence the manure should be removed before
the larvae reach the migratory stage; that is to say, removal is
necessary every three days, and certainly not less frequently than twice
a week during the summer months. A series of orders issued in 1906 by
the health department of the District of Columbia, on the authority of
the Commissioners of the District, covers most of these points, and
these orders, which may well serve as a model to other communities
desiring to undertake similar measur