146 FUMIGATION METHODS 
Last year in my largest house I only found it necessary 
to fumigate once, and until the violets were thrown out. 
this spring I never saw another aphis init. I cannot 
now give you exact information in regard to the cost 
of fumigation. 
‘‘T do not entrust the operation to any one, as the 
risk, which I believe to be great, I take myself. 
Therefore all the fumigation which I have done I have 
done alone, except with a friend to assist; but the 
people who work about the house have nothing to do 
with it. Fumigating is done about an hour or two. 
after dark. I grow Farquhar, Lady Campbell, and 
Imperial violets; also a few La France. Last year I 
had some of them in one house. ‘The leaves of the 
La France were slightly injured by an exposure of 
twenty-one minutes. 
‘“The black aphis were very prevalent; in fact, 
the plants were completely covered with them when I 
gave the application of which I have spoken, but it 
cleaned them out. I have used it also in violet frames. 
and ina mushroom house. In the latter case I used 
it with great strength. I found mice, snails, roly- 
polys, and earthworms dead in the morning. This I 
put in and allowed to stay all night. I have also 
found from experiments that nothing can breathe the 
gas and live. 
‘‘In my opinion no one can successfully grow 
violets, at least in this vicinity, who does not use the 
gas. I have now one house 23% feet wide by 200 feet 
long, one 20 feet wide by 1oo feet long, one 12 feet 
wide by 60 feet long, all devoted to the growing of 
violets.”’ 
