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RESIN OF JALAP IN RESIN OF SCAMMONY. 
ON THE DETECTION OF RESIN OF JALAP, RESIN OF GUAIACUM 
AND COLOPHONY, IN THE RESIN OF SCAMMONY. 
By M. Thorel. 
In expressing the opinion, some time ago, that the resin of 
scammony was the part of the drug that ought to be administered 
as a therapeutic agent, I conceived that this resin ought always 
to be prepared by the pharmaceutist himself. 
Whenever the pharmaceutist, from any cause, is prevented from 
preparing it, and is obliged to purchase that which is met with in 
commerce, it is necessary that care should be taken to ascertain 
that it is pure. 
Any adulteration would soon be discovered, unless the substance 
added was in small quantity or its action similar to that of the re- 
sin itself. Resin of jalap being of the latter class, and being at 
the same time cheaper than resin of scammony, has been used for 
adulterating it. The fraud is a very unjustifiable one, notwith- 
standing the fact that the substance used is somewhat similar in 
action, for no substitution of one agent for another should be 
toleiated in medicines. 
I propose, for the detection of this fraud, a method which is 
founded on the perfect insolubility of resin of jalap in rectified 
ether, and the solubility in all proportions of the resin of scammony 
in this menstruum. 
There are o f her substances, besides resin of jalap, which are 
used for adulterating resin of scammony, such as resin of guaia- 
cum and colophony, and these are still more objectionable, as they 
are inert. 
Resin of guaiacum may be easily detected by means of nitrous 
acid gas, or bichloride of mercury. 
There are several reagents which may be used for detecting the 
presence of colophony in resin of scammony. Among them is 
oil of turpentine, which dissolves colophony at common tem- 
perature, and leaves resin of scammony almost wholly unacted 
upon. 
But the best reagent for this purpose is sulphuric acid, which 
possesses the property of dissolving many resins, and of modifying, 
