REPORT OF J. P. STELLE. 
[33] 
I made some carefal experiments with dry London purple, undiluted with anything, 
for the purpose of deciding whether or not it could be applied successfully and made 
effeotual in this condition. The implement employed in the applications was the bel- 
lows-and-box arrangement already mentioned in connection with pyrethrum. With 
this I dusted double rows of cotton plants across a square acre, the worms upon them 
being iu strong force : 
No. 1, under side of leaves at the rate of two pounds of purple to the acre; No. 2, 
same, at the rate of three pounds to the acre, and No. 3, thrown over the plants gen- 
erally at the rate of two pounds to the acre. All the young worms still on the under 
sides* of the leaves of Nos. I and 2 were promptly cleared otF, but some large oues re- 
mained for several days on the upper sides of the leaves, though they did not seem to 
be feeding. The leaves were more or less scorched by the poison, especially on the 
rows dusted at the rate of three pounds to the acre. But the rows dusted promis- 
cuously at the rate of two pounds to the acre showed the best results — the worms were 
all cleared oil", while very little damage was done to the foliage. 
Of course a good deal of the scorching may be charged to the rudeness of the im- 
plement with which tin applications were made, it not distributingthe powderwith 
entire n _ularity. But even so imperfect a test settles it, in my mind, that there is 
really no need of diluting London purple with anything save air — a machine can be 
invented that would apply it in this condition as successfully as in any other. My 
idea of such a machine pictures something on the plan of the revolving 44 fan " or 
•• blower" used by blacksmiths or foundry men, with an attaclunent qualified to feed 
t he dr> purple in from a hopper only just so fast as needed. I think such a machine 
can be gotten up easily and w ith very little complication in either its construction or 
manner of working. 
With a view to testing whether or not the moth* of Aletia are killed by the appli- 
cation of London purple to the plants, I aflixed two largo dry -goods boxes each over 
a small living cotton-plant, as in the yeast experiment. The plant in No. 1 was care- 
fully sprayed on the under sides of the leaves with London purple in water at the 
rate of three-fourths of a pound to forty gallons. Nothing was put upon the plant in 
No. 2. Under each gauze-covered box, w ith the plants, were placed twelve lively 
Aletia moths, taken from my breeding box, where tin y had been two days without, 
food. Next day found six moths (b ad in No. 1 and two dead in No. 2. And the itt.rt 
day found three dead in No. Land none dead in No. 2. Replaced the dead moths with 
living specimens, after having sprayed both plants promiscuously with the same mix- 
ture as used at the beginning of the experiment. Next morning found four moths 
dead in No. 1 and seven in No. 2. 
At the time of the season w hen the Boll Worm was most actively at work, I made 
an experiment 1 ooking to a decision as to whether or not sprinkling the plants w ith 
London purple had any bad effect upon that insect after it had ceased to feed upon 
the leaves. Seh i t ing several heavily-fruited plants, I spread dry London purple care- 
fully over the bolls, applying it thinly with a camel'a-bairpencii. It protected every 
boll. Whilo a large per centum of the bolls on all the neighboring plants wero af- 
terwards bored into, not one to w hich I had applied the London purple was damaged 
in the least . 
I applied London purple to many eggs of Aletia, spreading it thinly over them, dry, 
w ith a camel's-hair pencil. I think it destroyed every egg so treated. 
PARIS GREEN. 
My experiments with this article were limited to a few applications made with the 
poison ruspended in water for the purpose of determining how small a quantity could 
be made effectual as a destroyer of the Cotton Worm. The poison was obtained of a 
dealer in Galveston, and was supposed to be as pure as any on the general market. It 
gave entire satisfaction, mixed in the proportion of one pound of Paris green to forty 
gallons of w r ater, and thrown over the plants promiscuously with a force pump in finely 
divided jets ; but less than one pound did not prove a decided success. This quantity 
entirely cleared oft* the worms, and did not seem to injure the plants in the least. I 
added neither starch nor flour; but to one application I added common salt in the 
proportion of two pounds to the forty gallons of water. The salt gave a greater speci- 
fic gravity to the water, thus, as I thought, aiding in the suspension of the'- Paris 
green. 
ARSENIC. 
The poison employed in these experiments was the common white arsenic (Jcidum 
arseuiosum) , costing, landed in Texas, from 3 to 4 cents per pound by the barrel. 
The first three tests were made with the poison in a dry state, applied undiluted to 
the plants by means of the bellow s dusting-implement already described. Each ex- 
periment covered two rows of cotton running across a square acre, and well stocked 
with worms in various stag' a of growth. 
03 CONG— AP -3 
