e PARALYSIS). In severe cases the coma deepens and
the patient dies, usually from interference with the breathing, or, less
commonly, from arrest of the heart's action.

The mechanism by which apoplexy is produced has been a matter of much
dispute; the condition was formerly ascribed to the pressure exerted by
the clot on the rest of the brain, but there is no increase of
intracranial pressure in an apoplectic fit occurring as a result of the
sudden closure of a large vessel by embolism or thrombosis. Suddenness
of the lesion appears to be, then, the essential element common to all
cases of apoplexy from organic brain disease. It is the sudden shock to
the delicate mechanism that produces the unconsciousness; but seeing
that the coma is usually deeper and more prolonged in cerebral
haemorrhage than when occasioned by vascular occlusion, and that an
ingravescent apoplexy coma gradually develops and deepens as the amount
of haemorrhage increases, we may presume that increase of intracranial
pressure does play an important part in the degree and intensity of the
coma caused by the rupture of a vessel. Apoplexy seldom occurs under
forty years of age, but owing to the fact that disease of the cerebral
vessels may exist at any age, from causes which are fully explained in
the article NEUROPATHOLOGY, no period of life is exempt; consequently
cases of true apoplexy are not wanting even in very young children.
Recognizing that there are two causes of apoplexy in advanced life, viz.
(1) sudden rupture of a diseased vessel usually associated with high
arterial pressure, enlarged, powerfully acting heart and chronic renal
disease, and (2) the sudden clotting of blood in a large diseased vessel
favoured by a low arterial pressure due to a weak-acting heart, it is
obvious that the character of the pulse forms a good guide to the
diagnosis of the cause, the prevention and warding off of an attack, and
the treatment of such should it occur.

Anything which tends directly or indirectly to increase arterial
pressure within the cerebral blood-vessels may bring on an attack of
cerebral haemorrhage; and although the identification of an apoplectic
habit of body with a stout build, a short neck and florid complexion is
now generally discredited, it being admitted that apoplexy occurs as
frequently in thin and spare persons who present no such peculiarity of
conformation, yet a plethoric habit of body, occasioned by immoderate
eating or drin