170 FUMIGATION METHODS 
pounds of cyanide were used in this building at one 
time. The four upper stories were fumigated first, 
and a few days later the basement and first floors. 
We demonstrated that this gas can be used even in the 
heart of a solidly built-up city block if properly 
handled. The building in question is located in the 
heart of the business center of the city. Every crack 
about the windows was pasted up with narrow strips 
of paper. We used string and bags, suspending 3% 
pounds of cyanide over each four-gallon jar. We had 
six jars each on the second and third floors and two 
each on the fourth and fifth floors. The gas was gen- 
erated after office hours at 7.30 and the windows were 
lowered from the outside about 12 o’clock, midnight, 
the same night. The windows in the fifth story were 
lowered first, and by opening a door below a draft was 
created through the elevator shaft carrying the bulk 
of the gas out above the building. The other windows 
were opened a few minutes later and the building 
aired the rest of the night, one man remaining on 
guard all the time. The results were very gratifying. 
The pests were thoroughly destroyed, and in addition 
seven dead rats were found on the basement floor and 
one on the third floor. 
Mills and elevators.—The following is from a Cana- 
dian firm: In connection with our use of hydro- 
cyanic acid gas for the extermination of the Mediter- 
ranean flour moth, we beg to report the following : 
The cubic contents of our buildings figure 290,472 
cubic feet, for which we used 151 pounds cyanide of 
potassium, 226 pounds sulphuric acid, and 338 pounds 
water. We distributed 150 crocks throughout the 
