benzoic acid and ecgonine.

Coca leaves and preparations of them have no external action. Internally
their action is similar to that of opium, though somewhat less narcotic,
and causing a dilatation of the pupil of the eye instead of a
contraction. When masticated, the leaves first cause a tingling in the
tongue and mucous membrane of the mouth, owing to a stimulation of the
nerves of common sensation, and then abolish taste owing to a paralysis
of the terminals of the gustatory nerves. They have a definite
anaesthetic action upon the mucous membrane of the stomach, from which
there come in large part those organic sensations which we interpret as
hunger. Hence it is possible, under the influence of coca, to go without
food or consciousness of needing it, for as long a period as three days.
The drug is not a food, however, as its composition and history in the
body clearly show, and the individual who comfortably fasts under its
influence nevertheless shows all the physical signs of starvation, such
as loss of weight. In small doses coca stimulates the intestinal
peristalsis and thus is an aperient, but in large doses it paralyses the
muscular coat of the bowel, causing constipation, such as is constantly
seen in coco-maniacs, and in those inhabitants of Peru and the adjacent
countries who take it in excess or are markedly susceptible to its
influence.

The injection of coca leaves has a very remarkable effect upon the
higher tracts of the nervous system--an effect curiously contrary to
that produced by their chief ingredient upon the peripheral parts of the
nervous apparatus. The mental power is, at any rate subjectively,
enhanced in marked degree. In the absence of extended experiments in
psychological laboratories, such as have been conducted with alcohol, it
is not possible to say whether the apparent enhancement of the intellect
is an objectively demonstrable fact. The physical power is
unquestionably increased, such muscular exercises as are involved in
ascending mountains being made much easier after the chewing of an ounce
or so of these leaves. Excess in coca-chewing leads in many cases to
great bodily wasting, mental failure, insomnia, weakness of the
circulation and extreme dyspepsia. For other pharmacological characters
and the therapeutic employments of coca see Cocaine.

FOOTNOTE:

[1] Garcilasso de la Vega, writing of the plant, says that it is
called _cuca_ by the Indians, _coca_ by the Spani