ers the severe;--and,
again, the attendant in the sick room may be attacked with the sore
throat and fever only, both of which may subside without any appearance
of a rash.

In conclusion, this disease is a complaint of infancy and childhood,
rather than of adult age; generally affects the same individual but
once during his life; and, though examples of a second attack have
occurred, such a circumstance is extremely rare.

Sect. VI.--MEASLES.

Measles consists of a fever, in which the mucous lining of the air-
passages is principally affected, and which, after about three days'
duration, results in an eruption of a red rash over the surface.

It depends upon a specific contagion;--occurs most frequently during
childhood and adolescence, though no age is exempt from it;--and affects
the system but once; a peculiarity to which an exception is very rare,
proved by the few instances of the kind which have been recorded.

The period at which the disease manifests itself after infection is
various,--generally about the ninth day; it has, however, been delayed
until the sixteenth.

DESCRIPTION OF THE DISEASE.--The child infected will be observed not to
be as well as usual, less active, and out of spirits; his appetite
will fail, and his sleep be restless and disturbed. It will soon be
evident that he has apparently taken a cold in his head, and that this
is accompanied by fever. His voice will be hoarse; there will be
frequent cough, headach, sneezing, running from the nose and eyes,--the
eyelids being somewhat swollen, and the eyes inflamed;--the skin will be
hot and dry, and he will complain of occasional chilliness. In the
course of the next two or three days, these symptoms will increase in
severity, and perhaps be accompanied by oppression at the chest and
hurried breathing, and towards evening by slight delirium.

On the fourth day, the rash will appear, but the symptoms will be
little, if at all, mitigated; indeed, they will sometimes increase in
severity. The eruption will first be perceived about the head and face,
in the form of small red spots, at first distinct from each other, but
soon coalescing, and forming patches of an irregular crescent-like or
semilunar figure, of a dull red colour, and slightly elevated (giving a
sensation of hardness to the finger), while portions of the skin
intervening between them will retain their natural appearance. At this
time the eruption will also be found on th