984 Wiscorisin Academy of Sciences, Arts, and Letters. 
An examination of the first of the foregoing tables reveals 
the fact that the yield is influenced to a very considerable extent 
by the condition of the drug from which the oleoresin is pre¬ 
pared. Thus, for instance, the amount obtained is less when the 
powdered whole rhizomes are used than when peeled rhizomes 
are employed. This is to be expected in view of the fact that 
the outer layers contain little that is soluble in the solvent 
(ether) usually made use of. It will also be noticed that na¬ 
tural causes, such as, locality in which the rhizomes are grown, 
and time of harvesting are important factors in this connec¬ 
tion. These influences will be brought out more clearly on an 
inspection of the following table which shows the results of this 
nature obtained by Ed. Schmidt. 
Table 12.— Effect of locality in which the rhizomes are grown and the time 
of harvesting on the yield of oleoresin. 
Time of harvesting 
Peeled rhizomes from— 
Whole 
rhizomes 
from— 
Forest 
near Paris 
Vosges 
Mts. 
Jura Mts. 
Vosges 
Mts. 
Per cent. 
Percent. 
Per cent. 
Per cent. 
Mav. 
4.00 
7.00 
6.40 
June...... 
4.80 
7.60 
7.00 
4.90 
July... 
5.60 
8.70 
8.00 
5.70- 
August. 
6.20 
9.00 
8.40 
6.00 
September. 
6.60 
9.60 
9.10 
6.40 
October. 
6.90 
9.80 
9.30 
7.00 
In addition to the comments already made with regard to the 
influence of the solvent on the yield, the observations of Dac- 
como and Sccocianti (1896) are of importance in this connec¬ 
tion. These investigators found that the amount of oleoresin 
obtained, when ether was employed for extracting the drug, de¬ 
pended to some extent on the purity of the former. Thus, 
ether, specific gravity 0.720 gave 10 per cent, of oleoresin, 
whereas, ether, specific gravity 0.756 yielded 17 per cent. It 
was further pointed out, however, that the greater yield was 
not desirable as in this case the preparation did not contain 
all of the therapeutically active constituents and in addition 
was more prone to form a deposit on standing. 
