• PARIS GREEN ITS USE AS A POWDER. 
145 
large series of trials with poisons in powder form convinced me tbat 
this waste cannot be materially lessened by a careful handling of the 
sieve, or by employing several more layers of muslin in addition to the 
one or two now generally used. Application by means of the bellows 
is too irregular, while application with the hand is, with some practice, 
considerably less wasteful. 
"The most economical distribution of the mixture I could devise, for 
experiments on a small scale, was by means of a stiff brush. A com- 
mon shoe-brush is dipped in a Hat vessel containing the mixture. 43 The 
greatest portion of the adhering poison is then shaken off by knocking 
with a stick on the handle of the brush. The still adhering poison is 
then thrown on the plants by drawing a stick across the brush. The 
poison can thus be applied from any direction, and the amount be reg- 
ulated at will. Three average-sized plants were accordingly dusted on 
September 2; the first very slightly from above, the two others from 
below. In applying from below, the poison finally covers both the un- 
derside as well as the upper side of the leaves. I am qnite unable, 
however, to calculate the amount of poison mixture I used, but it is cer- 
tain that each plant did not receive the tenth part of the amount it 
would have received in the applications with the sieve. The plants 
were dusted early in the morning, the poison adhering very well also to 
the underside of the leaves. There were numerous worms on all plants 
at this time, while others were continually hatching. A moderate rain 
shower about six hours after application washed off most of the poison 
applied from above, while it had but little influence on that applied 
from below. However, wherever there were holes in the leaves, the 
poison on the underside was converted into paste, and, in a tew places, 
washed away. 
M The application on the first plant proved to be of very little use, 
though 1 found three dead worms under the plant next morning. The 
two other plants were, however, fully protected for about live days, and 
almost entirely cleared from the worms, when the migratory worms over- 
ran them. Against the superior Dumber of these worms the poison 
was of no avail, though a vast number of them were killed before the 
plants were stripped. 1 have not the slightest doubt, however, that in 
ordinary times such slight application of dry Paris green from below is 
fully sufficient to protect the plants." 
That such application from below is not only practically possible, but 
c in be effected much more rapidly than the sieving method, will be de- 
monstrated further on in discussing the machines invented for this pur- 
pose. The adoption of the new machines will considerably reduce the 
cost of the dry application of Paris green without in the least lessening 
its efficacy. Its cost per acre of cotton, when applied with the sieve, 
ranges from 75 cents to $2, according to the first cost of material and 
different modes of application, or, again, to the size of the plants at the 
time of the application. 
63 CONG 10 
