s on the two inflamed surfaces of the membrane rubbing
against each other, and accordingly is relieved not merely by the
abatement of the inflammation, but also when either the two surfaces
become, as they often do, adherent to each other, or when fluid is
poured out into the cavity of the chest, and thus keeps them asunder.

I dwell on this, because when fluid is poured out, the most distressing
symptoms greatly abate, or even disappear, and parents sometimes put off
in consequence sending for the doctor, while yet, if unattended to, the
fluid may increase to so large a quantity as to press upon the lung, and
so interfere with the entrance of air, or it may, if the mischief is not
checked, change into matter, and then have to be let out by tapping the
chest, for just the same reason as it may be necessary to open an
abscess in any other situation.

Whenever, then, symptoms, such as I have described, come on, send at
once for medical advice, and do not let some diminution of suffering, or
slight general improvement, lead you to delay.

=Croup.=--I endeavoured to explain, a few pages back, the cause of that
peculiar sound which is heard in spasmodic croup. The contraction of the
opening of the windpipe changes the sound which passes through it, just
as the opening or closing the keys of a wind instrument modifies the
sound which it gives forth. But the windpipe is not simply a wind
instrument, it is a stringed instrument too, and the strings or vocal
cords, as they are termed, give forth, as they vibrate, tones now
deeper, now more shrill. The action of this delicate apparatus is
readily disturbed, if the nerve-supply to it is disordered by irritation
in some distant organ, and then the breathing is accompanied by the
peculiar sound of spasmodic croup, or in older children this may show
itself in a different way, as in the loud, barking cough heard in some
cases of constipation, or of disordered digestion; or another
illustration of it is furnished by the loud, long breath--the 'hoop,'
which gives its name to hooping-cough. But there is one sound that
sometimes attends the breathing of children, which more than any other
causes, and justly causes, the greatest anxiety to a mother; and that is
the sound which is characteristic of croup.

The word croup, which comes from the Lowland Scotch, signifies merely
hoarseness in breathing or coughing, and is therefore, strictly
speaking, the name of a sign of disease, rather th