This Treatise will contain the practical experience of forty years. Three preliminary Dissertations will be prefixed. 1st. How far Insanity ought to be considered a _mental_ affection. 2d. On the influence which individuals are capable of exerting on the minds of others, both in the sane and insane state: the latter of course becomes the basis of that regulation which is termed _moral management_. 3d. On the connexion between the sexual organs and the mind, including the disorders that have been termed nymphomania, furor uterinus, puerperal insanity, barrenness, impotence, and the attacks that supervene at the period of cessation. On the disorders that resemble and are not unfrequently confounded with Insanity, viz. Delirium, Hypochondriasis, Morbid Activity of Mind, certain degrees of Paralysis, and various nervous affections. An investigation of the existing laws that apply to Lunatics, Idiots, and persons denominated of _Unsound_ Mind: with an accurate examination of the degree of incapacity or imbecility that ought to subject them to legal protection. Reflections on the parliamentary inquiries relating to insane persons, and the regulations enacted respecting the houses in which lunatics are confined. Candid remarks on the establishment and duties of the Metropolitan Commissioners. Estimate of the probability of the lives of insane persons, and of those who have been visited with mental derangement; calculated for the guidance of assurance offices.