9 
FUMIGATING BOXES. 
For the purpose of experimenting and where only a few hundred 
plants are to be treated, a tight box may be made of 30 to 50 cubic 
feet capacity. The box should be as nearly air-tight as possible, 
with a removable cover and a small door at the bottom for intro- 
ducing the cyanide of potash into the bowl containing water and 
sulphuric acid, as shown in fig. 1. 
The wire trays shown in the same illustration are used in fumigat- 
ing cuttings of coleus or other plants. When desired the trays can 
be removed and pot plants set in the box and given such fumigation 
as desired. To prevent injury to the plants they should be so set that 
the foliage does not come within 18 inches of the bow] near the small 
door. When the plants are arranged the top is put on securely and 
a little water is poured into the bowl, and then sulphuric acid is 
added till steam is formed. The necessary amount of cyanide wrap- 
ped in a small piece of newspaper is then dropped into the bowl and 
the little door quickly closed. When the desired length of time has 
elapsed take off the cover and open the door and retire, so as not to 
breathe the gas. In a few minutes the gas will have sufficiently 
escaped so that the plants may be taken out and others treated in the 
same way. Injury (if there is any) to the plants may not show for 
two or three days, so, in the case of experimenting, conclusions should 
not be hastily drawn. The box may be used in the daytime if the 
work is done in a cool place. For experimental purposes and _ treat- 
ing plants on a small scale, a small greenhouse containing 1,000 
cubic feet, or less, is better than a box, as the results obtained with 
it are more reliable, and there is less danger of injury to the foliage. 
CONDENSED DIRECTIONS. 
(1) Carefully determine the cubic contents of the house and the 
amount of cyanide of potash to use. 
(2) Make the house as tight as possible. 
(5) Arrange so that the ventilators can be opened from the outside. 
(4) Place the jars and strings in position. 
(5) After dark attach the bags containing the cyanide to strings, 
as described, and find if they work correctly. 
(6) Hang the bags to one side and put water and acid into the 
jars; arrange protection and put the bags in place again. 
(7) When all is ready lower the bags into the jars by loosening 
the strings from outside. 
(8) After the proper exposure open the ventilators from outside, 
leaving them open from thirty to forty-five minutes before entering 
the house. 
(9) Next morning bury contents of the jars. 
