scles are caused to contract more vigorously, increasing their
working power without there being any secondary reaction leading to a
diminished capacity for work. Its action upon the circulation is
somewhat antagonistic; for while it tends to increase the rate of the
heart by acting directly on the heart muscle, it tends to decrease it by
stimulating the inhibitory center in the medulla.[188]

The effect on the kidneys is more marked, the diuretic effect being
shown by an increase in water, soluble solids, and of uric acid directly
attributable to the caffein content of the coffee taken. In the
alimentary tract coffee seems to stimulate the oxyntic cells and
slightly to increase the secretion of hydrochloric acid, as well as to
favor intestinal peristalsis. It is difficult to accept reports of
coffee accomplishing both a decrease in metabolism and an increase in
body heat; but if the production of heat by the demethylation of caffein
to form uric acid and a possible repression of perspiration by coffee be
considered, the simultaneous occurrence of these two physiological
reactions may be credited.

The disagreement of medical authorities over the physiological effects
of coffee is quite pronounced. This may be observed by a careful perusal
of the following statements made by these men. It will be noticed that
the majority opinion is that coffee in moderation is not harmful. Just
how much coffee a person may drink, and still remain within the limits
of moderation and temperance, is dependent solely upon the individual
constitution, and should be decided from personal experience rather than
by accepting an arbitrary standard set by some one who professes to be
an authority on the matter.

A writer in the _British Homeopathic Review_[189] says that "the
exciting effects of coffee upon the nervous system exhibit themselves in
all its departments as a temporary exaltation. The emotions are raised
in pitch, the fancies are lively and vivid, benevolence is excited, the
religious sense is stimulated, there is great loquacity.... The
intellectual powers are stimulated, both memory and judgment are
rendered more keen and unusual vivacity of verbal expression rules for a
short time." He continues:

Hahnemann gives a characteristically careful account of the coffee
headache. If the quantity of coffee taken be immoderately great and
the body be very excitable and quite unused to coffee, there occurs
a semilat