1084 Wisconsin Academy of Sciences , Arts, and Letters. 
pungent principles (gingerol) of the oleoresin of ginger with 
alkalies, whereby the pungent principle (capsicin) of the oleo¬ 
resin of capsicum remains unaltered. As it was subsequently 
found that the pungent principles of the former were not com¬ 
pletely destroyed by this treatment, Nelson proposed a modi¬ 
fication of the above methods, in which he makes use of 
manganese dioxide for completing the disintegration of these 
constituents. Full descriptions of these methods follow: 
Method of Garnett .and Grier (1907): Digest 1 gram of the oleoresin 
for 15 minutes on a water bath with a small quantity of caustic alkali 
dissolved in alcohol. Evaporate the solution to remove the alcohol and 
make the residue faintly acid with hydrochloric acid. Transfer the liquid 
to a test tube and shake it with 5 cubic centimeters of ether which have 
previously been used to rinse the dish. Allow the mixture to stand quietly 
and then taste the separated ethereal layer. If sharply pungent, adultera¬ 
tion with capsicum is indicated. 
Method of La Wall (1910): Add 10 cubic centimeters of half-normal 
alcoholic potassium hydroxide solution to 1 gram of the oleoresin contained 
in a shallow porcelain dish and evaporate to dryness on a water bath. Dis¬ 
solve the residue in 50 cubic centimeters of water and transfer the solution 
to a separatory funnel. Add 20 cubic centimeters of ether and shake vigor¬ 
ously. After allowing the mixture to stand until the ether has separated, 
run the latter off on a watch glass and expose it until the solvent has all 
evaporated. The residue should have a warm camphoraceous taste. A 
sharp pungent taste indicates adulteration with capsicum. 
Method of Nelson (1902) : 2 Add 10 cubic centimeters of double-normal 
alcoholic potassium hydroxide solution to one gram of the oleoresin contained 
in a porcelain dish and evaporate on a steam bath. Add about 0.1 gram 
of pow r dered manganese dioxide and 5 to 10 cubic centimeters of water, 
and continue heating for about 20 minutes, or until all of the volatile oil 
has been expelled. Cool, acidify with dilute sulphuric acid and extract 
at once with petroleum ether. Evaporate the petroleum ether solution in a 
small crucible, keeping the residue within as small an area as possible. When 
all of the solvent has evaporated, apply the tongue to the residue, being 
careful to keep the material on the tip. If capsicum is present, the char¬ 
acteristic burning sensation will soon be felt. 
The latter is the method which was employed in making the 
test in the laboratory. In no ease, however, was capsicum de¬ 
tected in the samples examined. 
2 Journ. Indust, and Eng - . Chem. (1910), 2, p. 419. 
