The use of ardent spirits or wine to a person predisposed to insanity, is always dangerous; under the same circumstances a long course of mercurial remedies has been found mischievous. The suppression of accustomed evacuations is also a frequent cause of mania, and the restoration of them not unfrequently removes the mental affection. Where there is in women an hereditary disposition to mania, it is frequently called into action immediately after parturition; in such cases, the prognosis is favourable;[540] on the other hand, it has been remarked that in our climate, women are more frequently affected with insanity than men; and it has been considered very unfavourable to recovery, if they should be worse at the period of menstruation, or have their catamenia in very small or immoderate quantities. We have already noticed local injuries of the head among the predisposing causes; we may also observe in this place, that they not unfrequently prove an exciting one; in the case of _Hadfield_ the insanity was occasioned by a blow on the skull. DISSECTION has thrown little or no light on the pathology of insanity; it must be admitted that a peculiar structure of the brain will predispose to madness, but there may exist many alterations in the structure of these parts too minute for the eye to observe, or the scalpel to expose. In some cases, however, the brain of the maniac displays an obvious deviation from the healthy appearances, as we learn from the testimonies of _Chiarugi_ in Italy, _Greding_ in Germany, and from _Dr. Haslam’s_ work in this country. The more general appearances would seem to consist in excessive determination of blood to the brain, with enlargement of its vessels; and effusion of fluids into its cavities; the membranes of the brain have also been found variously altered from their healthy state; ossifications have been observed on the _dura mater_; the _tunica arachnoidea_ has appeared thickened, and more or less opaque; and the _pia mater_ has not unfrequently appeared inflamed and turgid with blood; besides which _Dr. Haslam_ has recorded an appearance of air in the vessels of this membrane; nor is it uncommon to discover effusions of a watery fluid between these membranes. The medullary substance, when cut into, has seemed to contain more blood than usual; the consistence of the branular mass has moreover been stated, by different anatomists, to recede from its natural state in cases of insanity. _Bonetus_, in his _Sepulchret. Anatom._ has asserted that the brain of maniacs is so dry and friable that it may almost be rubbed into powder; but with respect to this we are disposed to doubt. _Morgagni_,[541] however, tells us that he has generally found the brain of such persons of considerable hardness; and _Mr. John Hunter_ has found it so tough as even to exhibit some degree of elasticity; _Dr. Baillie_ has also remarked, that when these changes take place in the