“The leaves of the _Erythroxylon_ approach in shape and size those of tea, but they have never the dentated margin; on the under side, a prominent and curved line on each side of the midrib serves to distinguish them from most other leaves known. When dried well, they are of a very pale green, deeper on the upper than on the under side; their odour is then agreeable, and even analogous to that of tea. When, on the contrary, the Coca has been dried less perfectly, this agreeable aroma is hardly perceptible, or rather is overpowered by a pungent odour, _sui generis_, recalling the abominable smell exhaled by the breath of the masticators of Coca, which is, in fact, this odour in a concentrated state. This _bouquet_, if I may so term it, is very perceptible on tasting the Coca, and serves, according to its abundance, in indicating its quality. On the other hand, in a concentrated infusion, and still more so in a decoction, it is a bitterness mixed with something styptic that more particularly strikes the palate. “As to the immediate physiological effects of this infusion, frequently-repeated trials enable me to assert that they are in general limited to a slight excitement, succeeded in most cases by some degree of sleeplessness. “The questions relative to the effects resulting from the use of Coca are less easily determined; we may begin, nevertheless, by stating that an immense majority of authors, both ancient and modern, who have written on the subject, have agreed in attributing to the Coca-leaf thus employed, virtues whose well-ascertained existence would warrant it being placed among the more beneficial products of the vegetable kingdom; and such would doubtless remain the admitted opinion, had not a modern traveller (Pöppig) completely shaken it by supporting an opposite view, that is to say, in attributing to Coca very pernicious effects, comparable, in fact, to those brought about by the excessive use of opium. “Such assertions, in the presence of reports so opposite as those I have cited, may well cause some astonishment. Individuals are, however, not wanting, who give us to understand that, if this traveller had not trusted too implicitly to the accounts of ill-informed persons, he had erred, at least, in too much generalising exceptional facts. For my part, I may say, that the researches that I have been able to make on the subject, in localities where the Coca is most in use, have shown me that the mastication of the leaf does sometimes produce evil consequences among Europeans who have not accustomed themselves to it from youth; and, in two or three cases, I have thought I could attribute to the abuse of this practice a peculiar aberration of the intellectual faculties indicated by hallucinations. But, in the countries which I have visited, on no occasion have I seen the results to reach the point instanced by M. Pöppig.