a swelling which
projects over the top of the windpipe, and causes the difficulty both in
swallowing and breathing. This swelling is the abscess; a prick with the
surgeon's lancet lets out the matter, and saves the child.

=Diseases of the Kidneys.=--The _kidneys_ perform very important duties
in carrying off from the system a large amount of useless material, and
thus supplement in many respects the action of the skin, and the
purifying influence which is exercised by the air on the blood, as it
passes through the lungs.

It is evident, therefore, that their disorder in any way must be a
matter of serious moment, though at the same time the knowledge of the
skilled doctor is needed to determine the nature and degree of the
ailment from which they are suffering, since that requires an
examination of the urine, both chemically and by means of the
microscope. My remarks on these diseases must consequently be few and
fragmentary.

In the grown person, what is known as _Bright's disease_ is of frequent
occurrence, assumes different forms, and depends on various causes. In
the child it is comparatively rare, and is scarcely ever met with except
as a consequence of a chill, or as a result of scarlatina. In these
conditions the kidneys become overfilled with blood or congested, and
the congestion may pass into inflammation, by which their structure may
be irreparably damaged. Dropsy is the great outward sign of the
affection--either slight swelling of the face, eyelids, and ankles, or
very great swelling of all the limbs, and even the abundant pouring out
of fluid into the belly. The degree of dropsy is, however, by no means
an absolute measure of the amount of kidney mischief. It therefore
behoves every parent to follow out all directions most scrupulously even
in cases of very slight dropsy, in order to guard against the risk of
permanent injury to the kidneys being left behind; and especially to
remember the liability to the occurrence of dropsy and disease of the
kidneys after scarlatina. Any check to the action of the skin while it
is peeling or desquamating, as it is termed, is especially liable to be
followed by these accidents. To avoid all risks as far as possible, I
have been accustomed for many years to insist on a child remaining in
bed for one-and-twenty days after the first appearance of the rash in
even the mildest case of scarlatina, and I am absolutely sure that it is
the height of imprudence ever to neglec