The term Apoplexy is derived from a Greek word, signifying a stroke or blow; and thus an attack of apoplexy is commonly called an apoplectic stroke. It is commonly caused by an effusion of blood into the substance of the brain; this at least is the most common variety, and next to this is where the blood is poured on the surface of the brain. There is a great variety in the number and size of these effusions. In some cases many ounces of blood are poured into the substance of the brain; in others the quantity is trifling, being sometimes as small as a pea, or even less. Examinations of the brain after death have shown that, in many cases of apoplexy, after a clot has been formed, nature commences, at an early period, a process of cure. The clot is gradually removed. There is a great difference in the length of time consumed in this operation; but, from the number of cases in which, after paralysis, recovery takes place, it is evident that this process is of very frequent occurrence. It appears, then, that the cure of apoplexy depends upon the absorption of the clot, and that as long as this remains unabsorbed the patient is in danger. In some cases absorption does not take place at all; the clot becomes organized, and in this way it is supposed that some of the tumours found in the brain are formed. "The source of an apoplectic effusion is very hard to be discovered; it appears generally to come from a number of minute vessels, for we are seldom or never able to trace it to the rupture of a vessel of any size."

The age at which persons are most subject to apoplexy appears to be from fifty to seventy. But apoplexy is by no means uncommon even in persons of tender age. Billard gives an instance of this in a child soon after birth. There are also several cases mentioned as occurring in children during the first three or four years. Andral gives the case of a boy of nine years of age, who died of apoplexy, with a vast effusion of blood. Stokes says: "One of the most remarkable cases of this kind I ever witnessed occurred in a child who had just been weaned. This child had been labouring for some time under symptoms resembling incipient Hydrocephalus, and then suddently got an attack of convulsions, followed by insensibility and paralysis of one side. On examining the brain after death, there were nearly three ounces of blood found effused in the base of the brain."

Cases of apoplexy are far more numerous between sixty and seventy than between seventy and eighty, and after eighty there appears to be still less danger of an attack.

The general opinion is that persons of stout build, with florid complexions, are most liable to apoplectic attacks; this, however, is a mistake, as persons of thin habit and pale complexions are even more liable. The disease has been observed to be most common in persons of ordinary development, next in persons of thin, spare habit, and last of all in the plethoric and fat.

Apoplectic cases may be divided into three classes. In the first and worst, and which generally proves fatal, a person, apparently in perfect health, will fall down in a fit of apoplexy, remain for a short time insensible and paralytic, and then die. In this case we find, after death, an enormous effusion of blood, or excessive congestion. In the second class we have an apoplectic seizure with insensibility, which disappears after some time, and the patient recovers his senses, but with paralysis of one side. In this case the effusion is more limited, and exists only on one side of the brain. In the third class we have an attack of a milder description; there is scarcely any loss of intelligence, and the paralysis is slight, generally affecting the muscles of one side of the face,or of one of the extremities.

In the worst cases we frequently have evident signs of determination of blood to the head; the face is swollen and the lips livid; there is swelling and fulness of the vessels of the neck, with heat of the head, a hot skin, and the pulse full and strong. In other cases, however, we have a feeble pulse and a cold collapsed state of the surface.

A few of apparently the worst cases, where both sides of the body are attacked with paralysis at the same time, will occasionally recover. Two cases are iven by Andral, a French surgeon; one of these, a female who had been for some time a patient at La Charite, died of Cancer of the stomach. Nine years before, she had had an attack of apoplexy; she had fallen down in a state of insensibility, and remained insensible for a considerable time, and this was followed by paralysis of both sides of the body, which continued for two years, after which she gradually recovered the use of her limbs. In another case, the subject of which died of visceral disease, the patient had, twenty-two years before, an attack of apoplexy with double paralysis, and recovered with the loss of the use of one side.

In paralysis arising from apoplexy there is the greatest possible variety. In some cases both sides being affected, in others only one, while in others there is only a single limb, or one side of the face. French writers describe a variety of paralysis, in which the right arm and the left leg, or the left arm and the right leg are affected; but these cases are very rare. We may also have complete paralysis of one side without any affection of the face. Dr. Stokes mentions the following case: "A gentleman of stout, muscular habit, and a strong full pulse, had been suffering for a long time from an obstinate gouty affection. From a repetition of the gouty attacks he got a chronic swelled state of the lower limbs, which continued for some time, he being in other respects in the enjoyment of excellent health. The swelling, however, preventing him from taking his usual exercise, he applied for advice. Laced stockings were recommended, the effect of wearing which was, that the swelling subsided, and the use of the limbs was restored. Between the period of the removal of the swelling and the paralytic attack, this gentleman enjoyed excellent health. At the end of that time, on attempting to go over a step that led into the yard, he found he could not accomplish his purpose, and struck his foot against the stone. He immediately became alarmed, and sat down, and soon after found that he had lost the power of using his arm. I saw him a short time after the accident, and found that there was complete paralysis of the arm and leg, but no distortion of the face or tongue, or the slightest loss of intelligence. He continued in this state for some time, and then recovered, but it was necessary to take a large quantity of blood from him. In the first bleeding, as the pulse was full and bounding, I took sixty ounces of blood from the arm, and I think it was owing to the activity of the measures adopted that he recovered so speedily."