ts nature that it is hazardous
to make many generalizations about the physiological behavior of coffee.
Most of the investigations that have been conducted to date have been
characterized by incompleteness and a failure to be sufficiently
comprehensive to eliminate the element of individual idiosyncrasy from
the results obtained. Accordingly, it is possible to select statements
from literature to the effect either that coffee is an "elixir of life,"
or even a poison.

This is a deplorable state of affairs, not calculated to promote the
dissemination of accurate knowledge among the consuming public, but it
may be partly excused upon the grounds that experimental apparatus has
not always been at the level of perfection that it now occupies. Also,
to do justice to some of the able men who have interested themselves in
this problem, it should be said that some of their results were obtained
in researches, distinguished by painstaking accuracy, which have
effected the establishment of the major reactions of ingested coffee.

_The Physiological Action of Coffee_

Drinking of coffee by mankind may be attributed to three causes: the
demand for, and the pleasing effects of, a hot drink (a very small
percentage of the coffee consumed is taken cold), the pleasing reaction
which its flavors excite on the gustatory nerve, and the stimulating
effect which it has upon the body. The flavor is due largely to the
volatile aromatic constituents, "caffeol," which, when isolated, have a
general depressant action on the system; and the stimulation is caused
by the caffein. The general and specific actions of these individual
components, together with that of the hypothetical "caffetannic acid,"
are considered under separate headings.

Coffee may be considered a member of the general class of adjuvant, or
auxiliary, foods to which other beverages and condiments of negligible
inherent food value belong. Its position on the average menu may be
attributed largely to its palatability and comforting effects. However,
the medicinal value of coffee in the dietary and _per se_ must not be
overlooked.

The ingestion of coffee infusion is always followed by evidences of
stimulation. It acts upon the nervous system as a powerful
cerebro-spinal stimulant, increasing mental activity and quickening the
power of perception, thus making the thoughts more precise and clear,
and intellectual work easier without any evident subsequent depression.
The mu