43 
Whale-oil soap dissolved by boiling at the rate of a third of a 
pound to the gallon of water proved too weak to destroy more than 
a comparatively small percentage of the bugs. With a half-pound 
to the gallon, the bugs reached by the liquid were practically all 
destroyed, and none of the plants were killed except where the ter- 
minal cavity in the so-called heart was filled, in which case the con- 
centration of the solution due to the gradual evaporation of the fluid 
caused the leaves to wilt and destroyed the plant. Three quarters 
of a pound to the gallon was perhaps a little more effective as an 
insecticide, but somewhat more dangerous to the plant. A few 
plants which were carefully treated were seen six days afterward 
to have been injured slightly, the injured leaves rolling up or grow- 
ing in distorted forms. Where as much as a pound and a half per 
gallon was used nearly all the plants were killed, and two pounds 
per gallon was fatal to every one. 
From the above it appears that a solution of whale-oil soap — one 
half pound to the gallon — is a safe and successful insecticide for 
corn-field use. As its cost, however, is about three times that of the 
four per cent, kerosene emulsion, it is scarcely to be recommended 
except on the score of occasional convenience. Where a barrel of 
the four per cent, emulsion costs thirty-four cents, a barrel of a 
half-pound solution of whale-oil soap will cost $1.12. 
Such fluid insecticides may best be applied during the cooler parts 
of the day, since the plant is less subject to injury then and the bugs 
feed more thoroughly. Enough of the liquid must be applied to wet 
the insects thoroughly, since otherwise they are likely to recover 
from its effects. For a complete operation, two and even three ap- 
plications may sometimes be necessary. 
Experiments with the Gasoline Blast-eamp. 
The use of the ordinary plumber's torch, or some modification 
of it, for the destruction of injurious insects on their food plants 
seems to have occurred independently to several persons during the 
last few^ years, and to have been tried with some care as a practical 
measure by several disinterested men competent to make exact ob-^ 
servations and to report results without bias or prejudice. 
Mr. S. A. McHenry, recently superintendent of one of the horti- 
cultural substations of the Texas Agricultural Experiment Station, 
is reported to have used it for several years against the harlequin 
cabbage-bug, and Professor J. M. Stedman, of the Missouri Experi- 
ment Station, has also used it against the same insect. Professor 
R. H. Pettit, of the Michigan Agricultural College, tried it on the 
