ves, as we have seen, hold
the heart in check, exercise a restraining control over it, very much as
the reins control an active horse. In health this inhibitory influence is
protective and sustaining. But now comes the narcotic invasion of
alcoholic drinks, which paralyze the inhibitory nerves, with the others,
and at once the uncontrolled heart, like the unchecked steed, plunges on
to violent and often destructive results.

[Illustration: Fig. 80.--Two Principal Arteries of the Front of the Leg
(Anterior Tibial and Dorsalis Pedis).]

This action, because it is quicker, has been considered also a stronger
action, and the alcohol has therefore been supposed to produce a
stimulating effect. But later researches lead to the conclusion that the
effect of alcoholic liquors is not properly that of a stimulant, but of a
narcotic paralyzant, and that while it indeed quickens, it also really
weakens the heart's action. This view would seem sustained by the fact
that the more the intoxicants are pushed, the deeper are the narcotic and
paralyzing effects. After having obstructed the nutritive and reparative
functions of the vital fluid for many years, their effects at last may
become fatal.

This relaxing effect involves not only the heart, but also the capillary
system, as is shown in the complexion of the face and the color of the
hands. In moderate drinkers the face is only flushed, but in drunkards it
is purplish. The flush attending the early stages of drinking is, of
course, not the flush of health, but an indication of disease.[34]

198. Effect upon the Heart. This forced overworking of the heart
which drives it at a reckless rate, cuts short its periods of rest and
inevitably produces serious heart-exhaustion. If repeated and continued,
it involves grave changes of the structure of the heart. The heart muscle,
endeavoring to compensate for the over-exertion, may become much
thickened, making the ventricles smaller, and so fail to do its duty in
properly pumping forward the blood which rushes in from the auricle. Or
the heart wall may by exhaustion become thinner, making the ventricles
much too large, and unable to send on the current. In still other cases,
the heart degenerates with minute particles of fat deposited in its
structures, and thus loses its power to propel the nutritive fluid. All
three of these conditions involve organic disease of the valves, and all
three often produce fatal results.

199. Effect of Al