Fever and other diseases amongst the insane attract attention in their mental as well as in their physical relations; and if at the same time both sane and insane suffer, a comparison of the cases is interesting. Besides, in an asylum the patients are especially under charge from the first faint indications of the malady, and the previous history, habits, and constitution of the individual arc familiar. In ordinary cases of fever amongst the community at large, the particular currents of the patient's thoughts and volitions do not attract special attention, save in protecting him from injury; and if insanity or other brain disease subsequently occurs, the features of the fever-poisoned brain are generally unknown and forgotten. Additional light might be thrown upon mental pathology and treatment, if such observations, sufficiently extensive, were correctly made and recorded. Alienists, on the other hand, have long noted the influence of physical diseases in the course of an attack of insanity; and recently cases from foreign journals were given by Dr. Arlidge,* where recovery has followed from wounds causing profuse suppuration in melancholia and general paralysis, from scarlatina in suicidal melancholia, from dysentery in mania and melancholia, from dysentery and acute rheumatism in monomania, from dysentery and a compound fracture of the elbow in religious monomania; lastly, profuse intestinal hæmorrhage is mentioned by M. Baillarger as ushering in recovery in a case of painful hallucination of vision consequent upon injury from a railway accident. Numerous other interesting cases are mentioned in the pages of our medico-psychological literature. Professor Laycock lately made known to me the case of a young girl, set. 15, an epileptic, who had typhus fever for five weeks, and never had a fit all that time. As she recovered, the fits returned as before (several daily), and ultimately the patient became acutely maniacal.