20 
accomplished, first, by harvesting as soon as the grain is ripe; second, 
by threshing as soon afterwards as possible. 
In the process of threshing or cleaning much infested grain is blown 
out with the chaff and dust, and the moths and many adult weevils 
are killed by the agitation which the grain receives; but the immature 
forms of these insects, concealed in the kernels as eggs, larvae, and 
pup, are apt to survive this treatment, and further measures are 
necessary for their destruction. 
For this purpose a quarantine bin is desirable, to be as nearly air- 
tight as possible, in which the newly threshed as well as the infested 
or suspected grain can be fumigated with bisulphide of carbon, accord- 
ing to the directions given on page 22. 
Fresh grain should not be exposed to insect attack by being placed 
in bins with “ weeviled” grain, or even housed under the same roof 
with such grain. If before storing in buildings that have been infested, 
the old grain be removed, the bins thoroughly cleaned, floors, walls, 
and ceilings brushed and scrubbed, the chances of infestation will 
be reduced toa minimum. If the storehouse has been badly infested, a 
fumigation with bisulphide 1s necessary. 
The recent appearance of that most pernicious of mill pests, the 
Mediterranean flour moth, on the Pacific Coast and in certain loca- 
tions in the Kast, has made indispensable the use of the bisuiphide of 
carbon and the quarantine bin, and has brought to the fore a number 
of mechanical devices for its control. One of these is called a “steam 
sweeper,” and certain mills in neighborhoods that are infested with 
this moth are already equipped with it. A steam pipe is run under the 
ceiling of each floor, and at intervals of about 25 feet a steam cock is 
placed, to which can be attached a hose for steaming the spouts and 
other portions of the infested machinery and all parts of the mill. The 
flour moth, as is well known, causes much trouble when in the larva 
or “‘worm” state by crawling into the spouts and elevator legs, where 
they spin their webs and clog the apertures. The liability of danger 
from this source may be obviated by the substitution of metal for the 
wooden apparatus generally in use, and already a metal spout has been 
patented and a metal elevator leg been devised for the express pur- 
pose of preventing this and other injurious insects from establishing 
themselves in these portions of the mill. Another device, called the 
“elevator brush,” has been called into use to prevent the larvee from 
choking up wooden spouts and elevator legs. 
In times when the Angoumois grain moth was so injurious in France 
a number of machines were devised for the treatment of infested grain. 
Into these the grain is poured and revolved while exposed to heat or 
subjected to a violent agitation which kills the contained insects. 
Cleanliness will accomplish much toward the prevention of injury 
from warehouse pests, the cause of a great proportion of injuries in 
granaries, mills, elevators, and other structures where grain and feed 
are stored being directly traceable to a disregard of neatness. Dust, 
