he has
no difficulty in passing water. Very commonly the patient complains of
pain in the head for some days after the return of consciousness.
Children often sleep a great deal during the first few days, but
sometimes they are very fretful.

In cases complicated by gross brain lesions the symptoms of concussion
may imperceptibly merge into those of compression or there may be a
"lucid interval" of some hours duration.

_After-Effects of Concussion._--The majority of patients recover
completely. A number complain for a time of headache, languor,
muscular weakness, and incapacity for sustained effort--_traumatic
neurasthenia_. Sometimes there is a condition of mental instability,
the patient is easily excited, and is unduly affected by alcohol or
other stimulants. Occasionally there is permanent mental impairment.
It is not uncommon to find that the patient has entirely forgotten the
circumstances of the injury and of the events which immediately
preceded it. In some instances the memory is permanently impaired. On
the other hand, it has occurred that a patient, after concussion, has
recovered his memory of a foreign language long since forgotten.

As it is never possible to determine the precise extent of the damage
to the brain, the immediate prognosis, even in the mildest cases of
concussion, should always be guarded. If the patient has been actually
unconscious, the condition should be looked upon as a serious one, and
treated accordingly.

_Treatment._--The immediate treatment is the same as that of shock.
Absolute rest and quietness are called for. When the symptoms begin to
pass off, the head should be raised on pillows to prevent congestion
and to diminish the risk of bleeding from damaged blood vessels in the
brain. The value of applying an ice-bag or Leiter's tubes with a view
to arresting haemorrhage inside the skull, is more than doubtful.
Lumbar puncture, venesection, or the application of leeches over the
temple or behind the ear may be employed with benefit. The use of
small doses of atropin and ergotin was recommended by von Bergmann.
The bowels should be thoroughly opened by calomel, croton oil, or
Henry's solution, and a light milk diet given. The patient is kept in
a shaded room, and should be confined to bed for from fourteen to
twenty-one days. It is often difficult to convince the patient of the
necessity for such prolonged confinement, but the responsibility for
curtailing it must rest upon h