32 LOSS THROUGH [NSBCTS THAI CARRY DISEASE. 
of fermenting vegetable refuse, accumulations of manure at the 
wharves, and in bedding in poultry pens. 
Still more recent investigations were carried on during 1908 by 
Prof. S. A. Forbes, State entomologist of Illinois, who has reared it 
in large numbers from the contents of paunches of slaughtered cattle, 
from refuse hog hairs, from tallow vats, from carcasses of various 
animals, miscellaneous garbage, and so on. 
All this means that if we allow the accumulation of filth we will 
have house flies, and if Ave do not allow it to accumulate we will have 
no house flies. With the careful collection of garbage in cans and 
the removal of the contents at more frequent intervals than 10 days, 
and with the proper regulation of abattoir-, and more particularly 
with the proper regulation of stables in which horses are kept, the 
typhoid fly will become a rare species. It will not be necessary to 
treat horse manure with chlorid of lime or with kerosene or with a 
solution of Paris green or arsenate of lead, if stable men are required 
to place the manure daily in a properly covered receptacle and if it 
is carried away once a week. 
The orders of the health department of the District of Columbia, 
published May 3, 1906, if carried out will be very effective. These 
orders may be briefly condensed as follows: 
All stalls in which animals are kept shall have the surface of the 
ground covered with a water-tight floor. Every person occupying 
a building where domestic animals are kept shall maintain, in con- 
nection therewith, a bin or pit for the reception of manure, and pend- 
ing the removal from the premises of the manure from the animal 
or animals shall place such manure in said bin or pit. This bin -hall 
be so constructed as to exclude rain water, and shall in all other re- 
spects be water-tight, except as it may be connected with the public 
sewer. It shall be provided with a suitable cover and constructed 
so as to prevent the ingress and egress of flies. Xo person owning 
a stable shall keep any manure or permit any manure to be kept in 
or upon any portion of the premises other than the bin or pit de- 
scribed, nor shall he allow any such bin or pit to be overfilled or 
needlessly uncovered. Horse manure may be kept tightly rammed 
into well-covered barrels for the purpose of removal in such barrels. 
Every person keeping manure in any of the more densely populated 
parts of the District shall cause all such manure to be removed from 
the premises at least twice every week between June 1 and October 31. 
and at least once every week between November 1 and May 31 of 
the following year. Xo person shall remove or transport any manure 
over any public highway in any of the more densely populated parts 
of the District except in a tight vehicle, which, if not inclosed, must 
be effectually covered with canvas, so as to prevent the manure from 
being dropped. Xo person shall deposit manure removed from the 
