e. Spinal apoplexy is one of the rarest forms of disease of the cord. The symptoms are said to be very much what might have been anticipated from our knowledge of cerebral apoplexy ; vio lent pain in the region of the effusion, general convulsions, sud den paralysis, which, in place of affecting one side of the body, occupies its lower half to an extent determined by the distance of the effusion from the top of the canal: it is generally unac companied by coma, and proves speedily fatal.
.f. General paralysis. This is the only form 'affecting both sides of the body which has its seat in the brain : seldom com plete until towards its close, it is marked by a general loss of muscular powers, an occasional difficulty in articulation, a tripping over or stuttering and slurring certain words, as in the early stages of intoxication. It is seen in its most typical form in the paralysis of the insane, where, along with the gradual abolition of the muscular power, there is a correspondingly gradual loss of mental consciousness, ending in perfect fatuity ; it is usually pre ceded by symptoms of alienation of mind having more or less the character of exaltation of ideas; the patient imagines that he has acquired an enormous fortune; or the quiet steady man of business becomes suddenly gay and extravagant ; the delusions seem always to have the character of happiness and contentment.
Pathological anatomy is not yet sufficiently advanced to point out in all such cases what are the actual changes in structure on which the disease depends, the brain being found in very various states after death.
A corresponding form of disease exists without the accompani meet of insanity, in which it is also quite impossible to predict the actual lesion that will be discovered ; and though in some rare cases no appreciable change of structure can be detected, yet their whole character warrants us in assigning disease of the brain as their cause. The consistency of the affection, its extension to one or other or both of the upper, as well as the lower, extremi ties, makes it probable that the seat of disease is above the spinal column; and, having satisfied ourselves that the vertebrae of the neck are free from disease or distortion, our next step is to an alyze with care the condition of the cranial nerves ; deafness, un equal action of the pupils, strabismus, &c., are to be taken as
evidence of disease in the cranium. It is worthy of remark that, while these nerves are affected only on one side, and one arm is perhaps decidedly weaker than the other, the legs are usually equally paralyzed. The paralysis is sometimes coincident with a condition of spasm which affords pretty conclusive evidence that the disease is situated in the brain itself.
Its progress is generally very slow, and the failure in muscular power may vary greatly in intensity in different parts of the body, being generally most complete where its existence was first recog nized. In the paralysis of the insane, the defect in speech is generally that which is first observed ; in other cases this is not so, but its existence is always very important in diagnosis. The absence of any other indication of disease besides loss of power, in some instances, has led to their being mistaken for cases of hysteria or hypochondriasis.
g. Paralysis agitans: although clearly not belonging to the class paraplegia, the few remarks to be made on this disorder will best follow the description of general paralysis. There is no evi dence of brain disease ; the intellectual faculties are unimpaired, the cranial nerves are not liable to be implicated ; indeed, it is not proved that its seat is the nerves themselves, but, like chorea, it consists in some disturbance of the relation between nervous influence and muscular movement; there is no anaesthesia. It is chiefly a disease of old age, comes on gradually with shaking of the head or of the extremities; these are, indeed, its only diag nostic features: it is occasionally left as the result of convulsions in infancy.
An analogous disease is seen in the tremor of those subjected to the constant action of mercurial vapor. The tremor, in this case, is only excited by voluntary muscular movement, the indi vidual at other times being perfectly still ; and its seat is most probably in the nervous system, as it sometimes presents the phe nomena of wakefulness and delirium. It is one of the examples of slow poisoning mentioned in an earlier part of this volume.