In the “Journal of Mental Science” for April, 1863, there appeared a paper by Dr. W. Carmichael McIntosh, entitled “Asylum Notes on Typhoid Fever.” In his introductory remarks, Dr. McIntosh notices the increased interest attached to the occurrence of physical diseases as observed in the insane, and the value of observations thereon, when the sane and insane suffer from the same disease and are under observation at the same time. There is then an opportunity of noticing the influence of such blood poisons as the scarlatinal and typhoid, as affecting two classes of the community; and as the patients are under medical observation from the very commencement of the illness, peculiar advantages are offered for a close investigation of all symptoms, mental and physical, from their first appearance. Dr. McIntosh further observes, “additional light might be thrown upon mental pathology and treatment, if such observations, sufficiently extensive, were correctly made and recorded. Alienists have long noted the influence of physical diseases in the course of an attack of insanity; and recently cases from foreign journals have been given by Dr. Arlidge, where recovery has followed wounds causing profuse suppuration in melancholia and general paralysis; scarlatina in suicidal melancholia; dysentery and acute rheumatism in monomania; 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.” It is with the view of adding a few cases to those which have already appeared in the various journals that the following examples of insanity, with intercurrent scarlatina, are published; so that when a sufficient number have been recorded they may be collected for comparison and further examination, and it may be that some useful and interesting results may be obtained. For as we are in the habit of watching the effects of drugs introduced by ourselves in cases of insanity, in the hope that ultimately we may arrive at a scientific method for such medicinal treatment, there appears no reason why we should neglect, but rather the reverse, the observation of cases in which, through contagion, a specific blood poison has been introduced into the system, and which produces characteristic and obvious symptoms. In the present state of matters one would scarcely feel inclined or be justified to run the risk of exposing an insane patient to the poison of typhus or measles for the chance benefit which might result to the mental state; but it is not unreasonable to think that some day we shall be able to modify the course of many diseases, perhaps mental among the others, as we now do in the case of small-pox through vaccination.