184 FUMIGATION METHODS 
containing hydrocyanic acid gas from fifty-thousandths 
of a gramme of potassium cyanide per cubic foot and 
in much less time than when soaked for twenty-four 
hours. 
Grains and other seeds soaked for twenty-four hours 
and then left for seven days in an atmosphere of hydro- 
cyanic acid gas will remain inactive while in the gas 
and from seven to twelve days after removal, but will 
eventually germinate to some extent if the strength of 
gas used does not exceed fifty-thousandths of a gramme 
of potassium cyanide per cubic foot, z.e., hydrocyanic 
acid gas is capable of holding seeds in an inactive state 
for two weeks or longer without destroying their vital- 
ity, even when the conditions are otherwise favorable 
for germination. 
Damp grains and other seeds treated with hydrocy- 
anic acid gas of any strength even for short periods of 
time should not be used for food until several hours 
after removing from the gas. The effect of the gas 
eventually passes off and the grain may be eaten with 
safety, although long exposure to the gas seems to 
render it unpalatable. 
In the first experiments conducted by the writer, 
where grain and manufactured produé¢ts were stored, 
the gas was generated at the rate of 0.10 to 0.12 
gramme per cubic foot. Very satisfactory results were 
secured, but further experiments showed that it was 
better to use from 0.20 to 0.25 gramme per cubic foot 
of space enclosed. It was found that a greater volume 
of gas remained in the building for a longer time 
where larger doses were used. At the same time no 
deleterious effets were observed either in the manu- 
