10 
BULLETIN No. 77b. 
Aesenites in Eau Celeste, and Eau Celeste Modified with Soda. 
Mixtures of Paris green and London purple, 1 pound each to 
100 gallons Eau Celeste and Eau Celeste modified with soda were 
made, and after standing 24 hours were applied to foliage and tested 
qualitatively for soluble arsenic. The foliage was almost completely 
destroyed and the quantity of soluble arsenic extremely high. 
Ammonia and sodium carbonate are greedy solvents of arsenites; 
hence, arsenites should not be mixed in these solutions as now made. 
Arsenites in Kerosene Emulsion. 
Faris green and London purple do not mix well with kerosene 
emulsion. The particles stick together and become lumpy .; besides, 
the emulsion is slightly decomposed by London purple, and the 
soaps used in making the emulsion are always alkaline and render 
the arsenites more soluble than in water. 
IV.—Conclusions. 
1. When soluble arsenic compounds were absent there was no 
injury to foliage. 
2. When soluble arsenic compounds were present the foliage was 
always “ scorched.” 
3. That the injury was in all cases in direct proportion to the 
amount of soluble arsenic compounds present. 
4. Consequently it is soluble arsenic compounds that “ burns ” 
and “ scorches ” foliage when sprayed with arsenites. 
5. That lime prevents this injury by changing soluble arsenic 
compounds to the insoluble arsenite of lime. 
6. That London purple and Paris green mixtures with lime may 
be applied to foliage with as great safety after one hour as ten days 
after mixing. 
7. Because all arsenites in London purple and Paris green capable 
of solubility are changed by lime almost immediately into insolu- 
able arsenite of lime. 
8. That the longer wdiite arsenic mixture with lime has stood 
before applying to foliage, the better. 
9. For the complete change to insoluble arsenite requires several 
days. 
10. That the above change can be greatly shortened by treating 
the white arsenic and lime together for a short time with boiling 
water. 
11. That when white arsenic is dissolved alone, and lime added 
afterwards, 6 to 24 hours are required for all soluble arsenic to be 
precipitated. 
