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there are three valuable remedial measures, viz, agitation of the grain, 
heating, and dosing with bisulphide of carbon. 
The value of agitating or handling grain is well known, and when- 
ever, as in elevators, grain can be transferred or poured from one bin 
into another grain pests are not likely to trouble. The benefit will 
depend upon the frequency and thoroughness of the agitation, and in 
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 from three to five hours, but is apt to injure the germ, and is not 
advised in case of seed stock. The simplest, cheapest, and most effectual 
remedy is the use of bisulphide of carbon. 
BISULPHIDE OF CARBON. 
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 sat- 
urated 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 bisulphide 
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 red. 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 24 to 36 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 bisulphide 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 bisulphide should be first distributed in the 
lower story, working upward 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. 
