4 BULLETIN 165, U. S. DEPARTMENT OF AGRICULTURE. 
In studying the use of quassiin as a contact insecticide it became 
desirable to determine in what solvents and solutions this com- 
pound was soluble. Table I gives the results of the experiments 
which were carried out with this purpose in view. 
= > 
TaBLeE I.—Results of solubility tests for quassiin,. 
{ 
No. | Material. Action. 
i | Chioroforms 2-2-2422. soa: Readily soluble. 
2). | eh there ee ee ee Not soluble. 
3a" Mothyl alcohol 22 =" )!=-ae Readily soluble. 
4, 7) EthyPalcohol: S2a22. 55 eee Do. 
5 ) ELOb Walter soe see sec ee Do. 
OG WCold water! 2 s225 02526... Sparingly soluble 1-1,200. 
cf Kerosene. 2 3. + ei eee Not soluble. 
Sissi: Gasoline* 2 2e-2 6542 ee Do. 
| 9 | Carbon tetrachlorid........- Do. 
10 BeNzMe si 22.2 Sh! eae ee Do. 
fle eurpentine 2 fees oe eee Possibly soluble. 
RESULTS OF TESTS WITH SOLUTIONS. 
12 | Potassium hydroxid....... Readily soluble, solution yellow. 
13 sf Sodium hydroxid >< 2225 ==. Do. 
14 | Calcium hydroxid......-..-..- Do. 
15 | Potassium cyanid........... Do. 
16 | Sodium carbonate.........-- Do. 
7S |r y drocyanic acid 22 o-- 2" sce. Do. 
18 | Ammonium hydrate.......- Do 
19 | Whale-oil soap AAT e 0. 
20) 05) Sodium chlorids-ss2 224. 28. _| Apparently insoluble. 
271) | Hydrochloriciacids:2- 2222-2: Do. 
|}. 22 “) Sulphuricacid 2-2-0 6 Do. 
123" | SNitricncid.s..2 4s eee ee | Do. 
DAY Aeeticgeid. 2-25 caeeac 250 Do. 
The foregoing table represents the results of experiments which 
were conducted with quassun in an attempt to determine some cheap 
solvent or solution, other than hot water, by which it could be 
extracted from the wood. ; 
EXTRACTION OF QUASSIIN FROM SOLUTIONS. 
It was found that when the solutions of potassium hydroxid, sodium 
hydroxid, sodium carbonate, etc., with quassiin, were acidulated 
with sulphuric acid, the quassiin could be readily removed in chloro- 
form. This process would apply when testing the percentage of 
quassiin in such solutions. | 
DETERMINATION OF PURITY OF QUASSIIN USED. 
Since the purity of the quassiin used in spraying experiments 1s 
an important factor in figuring proportions, an attempt was made to 
determine the amounts of material other than quassiin which might 
be present in the stock solution. 
Following a suggestion in Allen, tannin was added to an aqueous 
solution of quassiin taken from the stock solution. A fine precipitate 
appeared, but unfortunately it passed through an ordinary filter 
paper. 
