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for some time, as is often the case, become particularly favorable 
material for the nourishment and multiplication of a large number of - 
insect species. ‘To exterminate these necessitates the ‘treatment of an 
entire room or building. 
The fumigation of buildings.—Carbon bisulphid is used in fumigating 
milling establishments, warehouses, storage rooms, grain elevators, 
stores, houses, barns, etc., for the destruction of insects affecting 
stored cereals and vegetable products, manufactured food products, 
dried tobacco and its various products, drug-store insects, and house- 
hold insects which may be sufficiently numerous or injurious to war- 
rant such treatment. Besides being efficient for the destruction of 
such insects, it will also kill other animals, such as rats and mice, 
which it mav reach. The most favorable time for application may 
vary somewhat, as will be shown by the individual life histories of the 
insects treated. It would require too much space to mention all the 
minor details.* 
Preliminary investigation— When a fumigation of this kind is under- 
taken, a preliminary investigation should be made which should make 
clear the nature of the pest, its habits, its injury, and as much of its 
life history as may be necessary to show whether one time will be 
more favorable to treatment than another. The building or room 
should be examined, its tightness ascertained, and its floor area and 
cubical contents computed. Objections to treatment and unavoidable 
dangers should be considered. In short all the pros and cons should 
be carefully weighed before treatment is determined upon. 
Preparations for treatment.—The building should be made as tight as 
possible. If glass is out, it should be reset; doors and windows should 
be made to fit snugly, and a special examination should be made for 
cracks and leaks around the floors and lower walls. The place should 
be thoroughly swept and cleaned, and a coat of whitewash may some- 
times be desirable. The material infested may be exposed, and, if 
movable, placed on the floors. 
Shallow tin pans or plates make good evaporating dishes. The 
larger the evaporating area the better. There should be about 1 
square foot of evaporating surface to every 25 square feet of floor 
area, and each square foot of evaporating surface should receive from 
one-half to 1 pound of the liquid. These figures are, of course, only 
suggestive and approximate. Pans should be placed as high in the room 
as possible, sincethe vapor is so heavy that it settles most heavily to the 
lower parts. Care should be taken when placing the pans to see that 
they are nearly level, so as to hold the liquid, though ordinarily no 
particular harm will be done if some of it is spilled. It should not be . 
found necessary to lose time in adjusting such things after the appli- 
cation is begun. If there are special places which are difficult of 
1See Farmers’ Bulletin No. 45: Some Insects Injurious to Stored Grain. 
