1098 Wisconsin Academy of Sciences, Arts, and Letters. 
Specific gravity: The oleoresin has the highest specific 
gravity of any of the preparations of this class, specific grav¬ 
ities of 1.065 and 1.067 having been observed for the same when 
made with ether and acetone, respectively. Alcohol yields a pro¬ 
duct of somewhat greater density, whereas the use of petroleum 
ether gives an oleoresin of low specific gravity. The important 
factors influencing the specific gravity of this oleoresin, aside 
from the effect produced by the use of different solvents in its 
preparation, are thought to be the condition of the drug 1 when 
extracted and the presence of unevaporated solvent in the 
finished product. The results obtained in the examination of 
laboratory and commercial samples are given in the following 
tables. 
Table 93 —Specific gravities of oleoresins prepared in the laboratory. 
Sample 
No. 
Date 
Observer 
Solvent 
Specific 
gravity 
1 
2 
3 
4 
1910 
DuMez Netzel. 
Alcohol. 
At 25° C 
1.089 
1.067 
1.065 
1.037 
Acetone. 
Ether . 
Benzin... 
Table 94 —Specific gravities of commercial oleoresins. 
Sample 
No. 
Date 
Observer 
Source 
Specific 
gravity 
1 
2 
3 
1916 
DuMez..... .... 
Sharp & Dohme.. 
At 25° C 
1.065 
1.083 1 
1.086 
Sauibb & Sons. 
“ 
Lilly & Co..... 
1 The preparation had a slight odor of ether. 
Refractive index: The refractive index of the oleoresin, when 
prepared with acetone, was found to be 1.516 at 25 °C, which 
agrees fairly well with that obtained for the sample from Sharp 
and Dohme. The low refractive index observed for the sample 
from Lilly and Co. is thought to be due to the presence of un- 
1 See under the caption “Chemistry of the drug and oleoresin”. 
