978 Wisconsin Academy of Sciences , Arts, and Letters. 
Alcohol and water appear to be the impurities which tend 
to exert a deleterious influence upon the finished product. Thus, 
Daccomo and Scoccianti (1896) observed that ether containing 
a considerable amount of alcohol did not completely extract the 
therapeutically active constituents from the drug and that the 
oleoresin obtained was more prone to form a deposit than when 
ether of a greater degree of purity was used. See also page 984 
under “Yield of oleoresin.” Similar effects were observed 
by the firm of Caesar and Loretz (1899.) The presence of 
water is so great a factor in promoting decomposition 
(hydrolysis?) that the German Pharmacopoeia (1910) directs 
that the rhizomes be preserved over freshly burned lime, a 
procedure which was recommended by Hager as early as 1871. 
Further evidence of the undesirability of the presence of water 
is to be found in the Norwegian (1913) and Finnish (1914) 
pharmacopoeias, which direct that the ethereal tincture be dried 
with anhydrous sodium sulphate or fused calcium chloride pre¬ 
vious to the removal of the solvent by distillation. 
5. ) For a description of the various forms of percolators 
designed for extraction with volatile solvents, see Part I under 
‘ ‘ Apparatus used. ’ ’ 
6. ) All editions of the Pharmacopoeia, including the present, 
direct that the drug be extracted by the process of simple per¬ 
colation even though the advantages of a continuous extraction 
apparatus in the handling of a volatile solvent like ether have 
been repeatedly pointed out. See Part 1 under “Solvents” 
and under “Apparatus used.” 
Of special interest in this connection is the work of Matzdorff 
(1901), the results of which show that the therapeutically ac¬ 
tive constituents are not completely extracted by simple perco¬ 
lation as ordinarily carried out, but that complete extraction 
is effected in a comparatively short time with the use of a Soxh- 
let’s apparatus. 
7. ) In connection with the recovery of the solvent by dis¬ 
tillation, attention is again directed to the deleterious effect of 
the presence of moisture and to the manner in which the same 
is directed to be removed by the Norwegian and Finnish phar¬ 
macopoeias. See above. 
Attention is also invited to the pharmacopoeial directions re¬ 
garding distillation, namely that it be conducted on a water 
