930 Wisconsin Academy of Sciences, Arts, and Letters. 
glycerin and fusel oil. The following is the working formula 
finally devised by him: 
“Take any convenient quantity of the drug; for each ounce thus em¬ 
ployed, 1 y% fluid ounces of ether, and 1 fluid ounce or q. s. of benzin. 
Pack the drug in a suitable apparatus, add the ether, and when it has ceased 
to pass, pour on the benzin in the proportion of one fluid ounce for each 
ounce of the drug employed or until as much percolate has been obtained 
as equals the amount of ether employed. Eecover the ether by distilla¬ 
tion in the usual manner.” 
The process of Rittenhouse does not appear to have received 
much attention as there is no subsequent mention of it to be 
found in the literature. 
During the meantime Procter continued his work on the oleo- 
resins and in the same year (1866), he pointed out that prac¬ 
tically all of the oleoresinous material was to be found in the first 
portions of the percolate, and that a considerable quantity of 
menstruum could be saved by discontinuing the operation be¬ 
fore the drug was completely exhausted. The following table 
compiled by Procter clearly brings out this point: 
Table 6— Yield of oleoresin of cubeb to ether , alcohol and benzin. 
Quantity 
of cubeb 
Solvent 
Quantity 
of 1st 
percolate 
Yield of 
oleoresin 
Quantity 
of 2nd 
percolate 
Yield of 
oleoresin 
Total 
yield 
grains 
1000 
Ether 
Alcohol 
Benzin 
grains 
1000 
grains 
205 
240 
140 
grains 
1000 
2000 
grains 
14 
30 
25 
grains 
219 
250 
170 
The effect of Procter’s work is noticed in the 1870 and 1880 
editions of the United States Pharmacopoeia. Thus, the Phar¬ 
macopoeia of 1870 directed that twenty instead of twenty-four 
fluidounces (as formerly required) of percolate be collected for 
every twelve troyounces of drug, while the Pharmacopoeia of 
1880 required that only 150 parts of percolate be obtained for 
every 100 parts of drug taken. It should also be noted, that 
in the 1880 edition, the method of preparing the oleoresin of 
ginger was made to conform with that given for the other oleo- 
resins. 
