IN the course of an investigation of the resinous constituents of hop-flowers, the results of which have been published elsewhere, I observed that these substances, when extracted from the hops by means of ether, yielded a somewhat considerable quantity of valeric acid on oxidation with an alkaline solutioii of potassium perin anganate. I t occurred to ine at the time that this fact inight serve as the basis of a method for distinguishing between hops and quassia in fermented and other

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... , and the following experiments which I have since made show that such is the case. In the first place, quassia-chips themselves were extracted with dry ether, and the small quantity of extract so obtained was submitted to the action of alkaline pernianganate solution, but no veleric acid was obtained. I n order to arrive at the best conditions for the application of this method, f'ermented liquids of various kinds, bittered with hops on the one hand and with quassia on the other, were prepared in the laboratory in the following manner: