Every thing which diminishes the inordinate action of the heart, and relieves the over-distended vessels of the head, removes, and often instantly, the spasm and other symptoms of the disorder. Thus, a great flow of tears or of urine, discharge of offending ingesta from the stomach, unlacing of stays or bandages which compress too tightly the viscera, artificial or spontaneous hæmorrhages, affusion of cold water, particularly on the head, cold drink, fear, &c., by any of which actions the circulation is equalised, will terminate the affection. Delirium is a common symptom of hysteria; and this symptom is prolonged sometimes beyond the removal of the spasm or paroxysm. The functions of the brain are probably only sympathetically affected; but as in all other sympathetic affections, if often repeated, the brain at length retains the morbid action, and insanity is developed. Some go so far as to assert, that hysteria is of that class of maladies which, wherever it is manifested, betrays a maniacal diathesis. Occasional hysteria, however, in young and susceptible females whose nervous systems are always highly irritable, may certainly occur without any such suspicion. But habitual hysteria clearly approximates to insanity. It should, therefore, receive serious attention, and be as speedily as possible removed; more especially if it be complicated, as it often is, with hypochondriasis. And if this affection attack a male, double precaution should be taken lest it be converted into mental derangement. 8. Hydropic Effusions. There is no proof of a morbid action in the brain of insane persons so uniform as effusion of serum within the cavities and membranes. Such collections of water may be the effect of inflammation of the brain itself, or its envelopes, and yet no appearance of recent inflammation be discovered; for effusion may so entirely relieve the blood-vessels as to leave no signs but of distension. Serum is never found in any part, perhaps, except as a consequence of diseased vascular action, although that action may not have been so violent as to amount to inflammation. On the contrary, watery depositions within the encephalon are frequently the effects of simple increased vascular action, or of obstructed circulation. With very few exceptions, out of many dissections of the heads of maniacs, I have found serum in the ventricles, or between the membranes of the brain, or in the theca vertebralis. Effusions of serous fluid into the cavities of the brain have been asserted always to prove fatal ;* but this opinion is clearly as erroneous as that which pronounces it to be always a cause of mental derangement. There is little doubt that where there have been considerable accumulations within the cranium, still all the intellectual faculties have continued perfect. Cases are on record which seem to prove that the accumulation of serum within the cranium may influence the mental disorder; for sometimes the symptoms indicative of its presence have so rapidly disappeared, while reason has as quickly been restored, that it has looked almost like the effect of magic. Cases also occur where this morbid condition of the brain inducing insanity happens periodically, as if the exhalants and absorbents were in a constant state of action and re-action, and that there was a perpetual struggle between the morbid disposition of the one set of vessels and the vigour of the other. * Edin. Med. and Surg. Journ. No. lviii. p. 98. That collections of water within the encephalon may continue without disturbance of the mental functions, the following case is an example: - A very old gentleman had for several months been complaining of various sensations in his head, which he could not very well define; but he compared them to the running about of little chickens within his cranium. His pulse was small and irregular, and often fluttering; and sometimes he felt rather faint. One day, although there was nothing more than usual to indicate danger, yet he declared that he felt his death was near. He took some refreshment as usual, and afterwards commenced writing: suddenly he was faintish, and immediately expired. He had expressed a desire that his body should be examined. There was no morbid appearance but in the head; and there a most extraordinary quantity of fluid was collected. His senses were entire to the last. It would appear, from a case recorded, that the presence of fluid may operate on the external senses correspondently with its site within the encephalon : a girl about nine years old, with symptoms of water in the brain, whenever she was in an erect position was quite blind; on throwing her head back she felt a motion internally towards the occiput, and while she held it so, her vision was distinct but the blindness always returned when she sat up. She died shortly, and a very large quantity of fluid was found in the ventricles and other parts of the brain. Besides, we may refer to the numerous instances of chronic hydrocephalus, where the patients often evince great acuteness, and even precocity of intellect. : Not only the symptoms in the living denote the frequent presence of water in the brain, but dissections exhibit appearances of its having been long deposited there. From the pallor and flaccidity of the substance of this organ, and its membranes, and especially of the plexus choroides, it may be inferred, that they have been for some time undergoing a sort of maceration. The evidence therefore is more than presumptive, that hydrocephalus does exist in adults whose intellectual faculties are quite perfect, as well as in those whose mind is deranged. But many still insist that water in the brain is always a consequence of the maniacal action, and that such action cannot exist without producing this effect. The tendency of children to acute hydrocephalus before dentition is completed, when strong determination to the head prevails, strengthens the opinion that it is a disease of excessive excitement; and the best authorities coincide, that the symptoms of excitation do not appear to depend upon the effused fluids,* any more than mental derangement is consequent on effusion. If the cerebral excitation apparent in the first stage of hydrocephalus or mania originated in such a cause, then, upon dissection, accumulations of fluid within the encephalon would always be present. We find, however, that cerebral irritation may be so great as to produce all the symptoms of the first disease, and shall run through all its stages and destroy life, yet the pathognomonic sign whence the disease is named, viz. dropsy of the brain, shall be wanting; and so likewise insanity, however strongly developed, shall offer no trace of effusion. There is a striking analogy in the commencement and termination, as well as in the morbid dissections of hydrocephalus and mania; although the one is attended with symptoms of an acute, and the other of a chronic affection. In hydrocephalus the external senses are sometimes morbidly acute, especially to light and sound; to all sur *Remarks, &c. by Garnett, Med. and Phys. Journ. vol. v.; Cheyne on Hydrocephalus Acutus, p. 59; Abernethy's Surg. Obs. p. 93. rounding objects, some are painfully sensible; and the understanding suddenly acquires an aptitude not before observable. In others, the sensibility and the mental faculties seem obtunded. The same observations apply to insanity. What further attests that effusion is not the cause of the delirium in the first disease is, that after fury, convulsions, and insensibility, a little before death the intellects are often completely restored.* The same phenomenon often, as I have before remarked, occurs in insane persons at that awful crisis; and collections of water, apparently of long standing, have been afterwards found in the encephalon. Like insanity and apoplexy, too, the diathesis of hydrocephalus is hereditary; and where a predisposition in the organisation of the encephalon obtains, there increased impetus and fulness of the vessels of the head, whatever be the stimulating cause, will induce the disease peculiar to it. Again, as in the heads of children who died with all the attendant symptoms of hydrocephalus, so likewise in those of adults who have died of apoplexy or mania, no sign of any of these affections has been traced. Further, life itself is frequently extinguished, through the medium of a sudden impression upon the brain, in all these diseases, without the evidence which, à priori, we are led to expect of the cause of death. In this and other cerebral affections from accelerated circulation, death sometimes so rapidly follows, that the effusion, which, if the excitation had gone on, would shortly have happened, does not take place. Now, as effusion is a common termination of over-excited vascular action, which, when it commences, abates excitement, it must be considered as a salutary process of nature to relieve a morbid action. It is, therefore, not improbable, |