if not soon relieved is fatal. Purgatives are of no use, and
usually make matters worse. A surgical operation in very skilful hands
will relieve, and must be quickly performed when necessary.

In cases in which the one part of the bowels has not yet gone far into
the other, nothing more is required than a cold cloth gently pressed
over the parts. We have seen relief set in on the fifth or sixth change
of such a cloth, when nothing else was used whatever. When a hot bag,
or bran poultice, has been put on the back, and cold cloths
persistently changed over the bowels, the whole matter has been put to
rights, and natural motion of the bowels has been had within an hour
after the applications have been begun.

[Illustration: Interior of small intestine.]

There is, however, a stronger measure than merely heating the back and
cooling the front in this way. The patient may be put at once into a
sitting bath or small tub, and a panful of cold water poured or dashed
on to the bowels; they then contract so powerfully, and shorten
themselves so much, that all invagination, as it is called, is made to
cease instantly. We should be disposed to try the mildest method in the
first instance, unless the case is one in which the lock in the bowels
had just taken place. Then it might be well to dash the pailful of
water on so as to put all right at once, and afterwards simply to apply
such remedies as would tend to prevent a recurrence of the evil.

It is, however, usually the case that the distress has lasted some time
before an opportunity of doing anything occurs, inflammation, more or
less, has set in, weeks may have passed, and blundering treatment may
have done great mischief. Then it is safe to use the heat at the back,
and frequently changed cold cloths in front, so as to reduce the
inflammation, and contract the bowels more slowly, so as to remove the
obstruction. When these have been used for some time, if the
obstruction is not removed it will be well to resort to the stronger
measures. Nothing is more beautifully simple than the ordinary action
of the bowels. The healthful movement is like that by which an
earth-worm moves along the ground: so long as the tube is thus moving
its contents onward, by contraction and expansion, no part can pass
inside or outside that which is before it; but when one part loses
nervous tension, and expands without contracting quickly enough, the
part behind it tends to worm itself into it, and