DRY APPLICATION OF LONDON PURPLE. 
151 
overdoses of Loudon purple. In other cases the failure was plainly 
to be attributed to the imperfect implements used for the distribution 
of the dry and wet poisons. In still other cases the cause of the fail- 
ure could not be made out. The conelusions we arrived at during the 
season of 1<S79, after a long series of trials made by ourself and Mr. 
Seh win/, and assisted by the most experienced planters in the vicinity 
of Columbus, Tex., and which were published in the first edition of 
this work) have been proved coriect by the experience of subsequent 
years, and wherever pure and genuine London purple has been applied 
according to the directions, it has always given satisfactory results. 
It should be remembered that the introduction of a new remedy, 
especially if it is not without drawbacks, is always a difficult task, and 
experience must be bought at the cost of disappointment and failure. 
We need only recall to the reader the history of the introduction of the 
Paris green, and how long it took before its efficacy was firmly estab- 
lished, and before the farmers and planters had gained full conlideiice 
that it was a perfect remedy for some of our worst insect enemies. 
London purple has, in common with all arsenical poisons, the disadvan- 
tage of danger, but it is one of the cheapest remedies of this class, being 
a mere refuse which, from its poisOUOUS nature, was a drug to the manu- 
facturers, and had to be gotten rid of by being dumped long distances 
out at sea. This substance can be put upon the market at the bare 
cost of transportation. It can be sold in New York at the low rate of 
G cents per pound, and there is no reason why it should not be obtained 
at any of the large shipping points in the South at figures ranging be- 
tween 7 and 10 cents a pound. This means virtually that the cost of 
destroying the worms by this powder is reduced to such a minimum as 
to depend mainly on the labor and the other ingredients or diluents 
employed; in other words, that, while the planters, as heretofore, were 
obliged to pay as much as 81 for the first cost of the active poison 
needed for one acre, and never less than 15 cents, they may now obtain 
it for from 3 to 5 cents. 
An advantage of minor importance is its red hue, as it colors the 
ingredients SO as to prevent their being mistaken for harmless material. 
The finely pulverized condition of the purple seems to be of less ad- 
vantage than we were formerly inclined to believe, as it increases the 
caustic power of the poison upon the plants. Finally, its cheap price 
removes the temptation of adulterating the poison, as every adultera- 
tion would prove more expensive than the genuine article. 
Dry application. — Experiments on a large scale have been made with 
the dry application at the rate of 2 pounds to 18 pounds of diluents, 
also at the rates of 1, J, i, and J pound to 18 of thediluents. The last 
proved only partially effectual, and in no case were the plants injured 
or the leaves even burned. In all but the last case the worms were 
killed, but as the mixture, at the rate of J pound, was applied with 
g; eater care and regularity than is generally had on a large scale, and 
