ompose late, hence in a fresh body
putrefaction of the lungs is absent; in a putrefied child, if the lungs
sink, it must have been stillborn. The so-called _emphysema pulmonum
neonatorum_ is simply incipient putrefaction.

The lung test simply shows that the child has breathed, but affords no
proof that the child has been born alive. The child may have breathed as
soon as its head protruded, the rest of the body being in the maternal
passages. The child is not born alive until it has been completely
expelled, although it is not necessary that the umbilical cord should
have been cut.

In addition to these tests, live birth may be suspected from the
following conditions: The _stomach_ may contain milk or food, recognized
by the microscope and by Trommer's test for sugar; the _large
intestines_ in stillborn children are filled with meconium, in those
born alive they are usually empty; the _bladder_ is generally emptied
soon after birth; the _skin_ is in a condition of exfoliation soon after
birth. The _organs of circulation_ undergo the following changes after
birth, and the extent to which these changes have advanced will give an
idea of how long the child has lived: The _ductus arteriosus_ begins to
contract within a few seconds of birth; at the end of a week it is about
the size of a crow quill, and about the tenth day is obliterated. The
_umbilical arteries and vein_: the arteries are remarkably diminished in
calibre at the end of twenty-four hours, and obliterated almost up to
the iliacs in three days; the umbilical vein and the ductus venosus are
generally completely contracted by the fifth day. The _foramen ovale_
becomes obliterated at extremely variable periods, and may continue open
even in the adult.

Importance of late has been attached to the _stomach-bowel test_. If the
stomach and duodenum contain air, and consequently float in water, the
chances are that the child did not die immediately after birth; this is
known as Breslau's second life test, and the lower the air in the
intestinal canal, the greater is the probability that the child survived
birth.

The umbilical cord in a new-born child is fresh, firm, round, and bluish
in colour; blood is contained in its vessels. The cord may be ruptured
by the child falling from the maternal parts in a precipitate labour,
and the ruptured parts present ragged ends. It is seldom that a child
bleeds to death from an untied or cut umbilical cord, and the chances in