6 
BULLETIN No. 77b. 
arsenic at the time of the first application, had not gone into solu¬ 
tion to be precipitated by the lime, and hence dried upon the leaves 
as white arsenic and was dissolved b} r the second application and 
then burned the leaves. It would be" safer, where white arsenic is 
used, to get it all into solution and allow it to be changed by lime 
into the insoluble arsenite of lime, thus removing danger of injury 
from a second application, from dew, or light rain. Here is an 
arsenite very much the same as London purple, that can be used 
with as great freedom as the latter, even after lime has been added 
to render it harmless to foliage. More of this later. 
Again, it will be seen from Table I that lime, in all cases where 
it was added to the mixtures at the time they were made, changed 
immediately all soluble arsenic compounds into insoluble ones as 
fast as they came into solution. The Bordeaux mixture contained 
sufficient lime, and it was not necessary to add more. 
Table II.—SHOWING AMOUNT OF SOLUBLE ARSENIC COMPOUNDS 
EXPRESSED AS ARSENIC TRIOXIDE (As 2 0 3 ) ARSENICAL MIXTURE 
AT DIFFERENT TIMES. 
1 Hr. Am’t 
as 2 0 3 in 
3 Hrs.Am’t 
As 3 0 3 in 
5 Hrs.Am’t 
As o0 3 in 
7 Hrs.Am’t 
As 2 0 3 in 
24Hrs.Amt 
As 2 O 3 in 
10 
Days.A’mt 
As 2 0 3 in 
MIXTURE. 
1 gal. 
100 gals. 
quS 1 
1 
GO 
r—“1 
bfi 
O 
0 
i-H 
1 gal. 
100 gals. 
IS 
be 
H 
100 gals. 
1 gal. 
•sp?3 oor 
1 gal. 
100 gals. 
Grms 
Grms 
Grms 
Grms 
Grms 
Grms 
Grms 
Grms 
Grms 
Grms 
Grms 
Grms 
*1 lb. white arsenic in 
100 t'als. water. 
.053 
5.3 
.223 
22.3 
.276 
27.6 
.333 
33.3 
.628 
62.8 
4.098 
409.8 
1 lb white arsenic and2 
lbs. lime In 100 gals, 
water- 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
1 lb. white arsenic and 
1 lb. lime in 100 gals 
water... 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
1 lb. London purple in 
100 gals, water_ 
.517 
51.7 
.520 
52.0 
.522 
52.2 
.530 
53.0 
.571 
57.4 
.595 
59.5 
1 ib. London purple 
and 2 lbs. lime in 100 
gals, water.. 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
1 lb. London purple 
andS'lbs. lime in 100 
gals, water- 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
1 lb. Paris green in 100 
gals, water. 
.057 
5.7 
.060 
6.0 
.061 
6.1 
.058 
5.80 
.066 
6.6 
.081 
8.1 
1 lb. Paris green and 1 
lb. lime in 100 gals, 
water. - 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
1 lb. Paris green in 100 
gals. Bordeaux mix¬ 
ture... 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
1 lb. London purple in 
100 gals. Bordeaux 
mixture..- 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
0 
* 1 pound equals 453>£ grams. 
Table II shows the amount of soluble arsenic compounds, 
expressed as grams of arsenic trioxide (As 2 0 3 ) in 1 gallon and in 
100 gallons, in arsenical mixtures at different times alter mixing 
