even larger, soft,
elastic, painless, under the unchanged scalp, but presenting the
peculiarity of having a hard raised margin with a distinct edge, which
gives to the finger passed over it the sensation of a bony ridge, beyond
which the bone seems deficient. This tumour is due usually to the same
cause as that which produces the other temporary puffy swelling of the
scalp, only the pressure having been more severe, blood has actually
been forced out from the small vessels under the membrane which covers
the skull, and hence its gradual increase, its definite outline; and
hence, too, the bony ridge which surrounds it, and which is due to
nature's effort at cure, in the course of which the raised edge of the
membrane covering the skull (the _pericranium_) becomes converted into
bone.

When the nature of these swellings was not understood, they used to be
poulticed, and to be opened with a lancet to let out their contents. We
know now, however, that we have nothing to do but to let them alone;
that by degrees the blood will be absorbed and the tumour will
disappear, and as it does so we may trace the gradual transformation of
the membrane which covered it into bone, as we feel it crackling like
tinsel under the finger. Two, three, or four weeks may be needed for the
entire removal of one of these blood-swellings. The doctor will at once
recognise its character, and you will then have nothing to do but to
wait--often, unhappily, so much harder for the anxious mother than to
meddle.

=Ruptured Navel.=--There is a period some time before the birth of a
child when the two halves of its body are not united in front, as they
become afterwards; and hare-lip or cleft-palate sometimes remains as the
result of the arrest of that development which should have closed the
fissured lip or united the two halves of the palate.

In a similar way it happens sometimes that though the skin is closed,
the muscles of the stomach (or, more properly speaking, of the belly)
are not in the close apposition in which they should be, so that the
bowels are not supported by the muscles, but protected only by the skin.

More frequently than this, especially in the case of children who are
born before the time, the opening through which the navel string passes
is large at birth, and fails to close as speedily and completely as it
should do afterwards. When everything goes on as it ought, the gradual
contraction of the opening helps to bring about t