iW 
as the thorough cleansing of bins before refilling, constant sweeping, 
removal of waste harboring insects from all parts of granaries and mills, 
andeare to prevent the introduction of “ weeviled” grain, there are three 
valuable remedial measures, viz, agitation of the grain, heating, and 
dosing with bisulphide of carbon. 
The value of agitation 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 thoroughness of the agitation, and in France machines 
for shaking the grain violently have been used with success. 
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 
however, 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 bisuphide 
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 arod. In moderately tight bins no further precau- 
tion than to close them well need be taken, but in open bins it will be 
necessary to cover the top with a blanket to prevent the too rapid dis- 
sipation 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 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 upwards 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. 
5481—No. 19-——2 
