43 
France machines for shaking the grain violently have been used with 
success. Winnowing weeviled grain is also an excellent preliminary 
treatment. 
Raising the temperature of the grain in closed retorts or revolving 
cylinders to 130° to 150° F. will kill the inclosed insects if continued 
for three to five hours, but is apt to injure the germ, and is not ad- 
vised in case of seed stock. The simplest and most effective remedies 
are the use of either bisulphid of carbon or sulphur dioxid. 
BISULPHID OF CARBON.? 
Character and method of application.—This is a colorless liquid with 
very offensive odor, which, however, passes off completely in a short 
time. It readily volatilizes, and the vapor, which is very deadly to 
insect life, is heavier than air and settles and fills any compartment 
or bin in the top of which the liquid is placed. It may be distributed 
in shallow dishes or tins or in saturated waste on the top of grain in 
bins, and the gas will settle and permeate throughout the mass of 
the grain. In large bins, to hasten and equalize the operation, it is 
well to put a quantity of the bisulphid in the center of the grain by 
thrusting in balls of cotton or waste tied to a stick and saturated with 
the liquid, or by means of a gas pipe loosely plugged at one end, down 
which the liquid may be poured and the plug then loosened with a 
rod. Prof. H. E. Weed reports that in Mississippi the chemical is 
commonly poured directly onto the grain. In moderately tight bins 
no further precaution than to close them well need be taken, but in 
open bins it will be necessary to cover them over with a blanket to 
prevent the too rapid dissipation of the vapor. The bins or buildings 
should be kept closed from twenty-four to thirty-six hours, after 
which a thorough airing should be given them. 
Limited quantities at a time may often be advantageously subjected 
to treatment in small bins before being placed for long storage in 
large masses, and especially whenever there is danger of introducing 
infested grain. 
The bisulphid is applied at the rate of 1 pound to the ton of grain, 
or a pound to a cubic space 10 feet on a side. 
In the case of mills, elevators, or larger granaries the application 
may be best made on Saturday night, leaving the building closed over 
Sunday, with a watchman without to see that no one enters and to 
guard against fire. The bisulphid should be first distributed in the 
upper story, working downward as rapidly as possible to avoid the 
settling vapor, using the substance very freely in waste or dishes at 
all points of infestation and over bins throughout the building. If 
the building be provided with an exterior means of descent (such as 
“See Farmers’ Bulletin No. 145, Carbon Bisulphid as an Insecticide. 
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