Jo 
somewhat resembling the down on the seeds of thistles separated out. 
These were composed of bisulphide of lime (CaS,) and being freely solu- 
ble in water, were dissolved when the balance of the water was added. 
In this action all of the sulphur had been incorporated with the lime, 
since the residue when dried would not ignite. Added a sufficient 
quantity of water to the above solution and sprayed an apple tree with 
it at 10:30 a. m. Mareh 18, sun shining, light breeze. 
About 14 hours after making the above experiment it began to rain 
very gently and this was continued for 24 hours. April 23, I found a 
great many living San José scales on this tree. At the time of making 
the above test I also sprayed some of the solution on a branch of a 
peach tree in full blossom, but this did not appear to produce any in- 
jurious effect upon the blossom, since at the time of my visit on the 
23d of April this branch bore as many peaches as did any of those L 
had not sprayed. It seems almost certain that the rain, coming on so 
soon after the wash was applied, rendered neutral the effect of the 
above solution on the scale insects sprayed with it. I have seen 
orange trees that had been sprayed with the resin wash on a certain 
day and a rain occurred during the night following the application ; 
but the wash did not prove fatal to nearly as large a percentage of the 
red scales as would bave been the case had no rain occurred. 
On the same day that the above test was made (March 18), I also 
tried the above mentioned lime and sulphur solution at half strength, 
but it did not produce any apparent effect upon the San José scales 
infesting the tree sprayed with it.. It was now too late in the season 
to make additional tests of this solution, but [ hope to be able to fol- 
low up this subject during the coming winter. 
From the above experiments it would appear that neither lime, salt, 
nor sulphur when used separately are effectual in destroying the San 
José scale; and the same is true in regard to any two of them when 
used in combination, except, perhaps, the lime and sulphur, which have 
not as yet been sufficiently tested. It is very probable, however, that 
these two ingredients give to the wash its insecticidal property, while 
the addition of the slaked lime and salt simply impart stability to the 
wash, rendering it less liable to be washed off the trees by the winter 
rains. Should this surmise prove correct, then the directions given at 
the head of this article for preparing this wash should be changed, an 
equal number of pounds of lime being required with the 33 pounds of 
sulphur, instead of only 21 pounds of lime, as at present used. 
I experienced considerable difficulty in preparing and applying this 
wash, owing to the fact that some of the materials used are not solu- 
ble in water, necessitating an almost constant stirring of the solution 
while it is being sprayed upon the trees. On this account it is quite im- 
possible to spray it uniformly upon all of the trees, and this difficulty 
has also been experienced by each of our fruit-growers who have used it 
and with whom [ have conversed upon the subject, or who have written 
25910—Bull. 2 3 
