Dii Mez—The Galenical Oleoresins. 
1091 
spectively possess an advantage over alcohol in that they ex¬ 
tract less inert material and yield products which are softer 
in consistence and conform more closely in their general 
properties to the other members of this clbss of preparations. 
The products obtained, even when using acetone or ether, are, 
however, more of the nature of an extract than an oleoresin. 
A better solvent for use in this connection would appear to 
be petroleum ether. While, it has apparently never received 
consideration for this purpose, it appears to be particularly 
well adapted to the same in that it completely extracts the 
valuable constituents of the drug (see soft resins, page 1095) 
with but little of the inert material and yields a product of 
such consistence that it can be poured. 
3) For a description of the various forms of percolation con¬ 
forming to the pharmacopoeial specifications for use in this 
connection, see Part I under “Apparatus used.” 
4) The various editions of the Pharmacopoeia in which this 
preparation has been official have directed that the material 
composing the oleoresin be extracted from the drug by simple 
percolation. In the earlier editions, percolation was directed 
to be continued until a certain definite amount of percolate 
was obtained, whereas, the pharmacopoeias of 1890 and 1900 
required that the operation be continued until the drug was 
exhausted. In either case, the quantity of solvent required is 
considerably greater than that which is necessary to com¬ 
pletely exhaust the drug when some form of continuous ex¬ 
tractor is used. Since the quality of the finished product is 
the same in both cases, it is thought that the later method of 
extraction is to be preferred. 
5-6) Owing to the fact that certain constituents of the oleo¬ 
resin are prone to undergo changes when the latter is exposed 
to the air (see page 1088 under “Drug used, its collection, pres¬ 
ervation, etc.”), the pharmacopoeial directions, that the last 
portions be allowed to evaporate spontaneously, are unfortu¬ 
nate. It is thought that a better procedure would be to evap¬ 
orate the solvent completely at the temperature of the water 
bath, thereby considerably shortening the time of exposure. 
8) For the reasons just mentioned, the finished product 
should be kept in well-stoppered bottles. 
