During the past few years there have been published, both in this country and on the continent, several comprehensive treatises on the subject of insanity, as well as new editions of older works. In England there has been issued a new edition of the volume by Drs. Bucknill and Tuke, a volume on ‘Obscure Mental Disease,’ &c., by Dr. Forbes Winslow. In Germany, a new edition of the work of Griesinger, ‘Die Pathologie und Therapie der Psychischen Krankheiten;’ and in 1859, ‘Lehrbuch der Psychiatre,’ by Neumann, and ‘Allgemeine Pathologie der Seele,’ by Wachsmuth, each of which enjoys an extensive reputation. In France, a ‘Traité Elémentaire et Pratique des Maladies Mentales,’ par Dr. Dagonet, of Strasbourg; ‘Traité Pratique des Maladies Mentales,’ par Dr. L. V. Marcé, of Paris. In 1860, ‘Traité des Maladies Mentales,’ par Dr. B. A. Morel, of Rouen; in 1859, ‘Traité des Maladies Inflammatoires du Cerveau,’ par le Dr. L. F. Calmeil. It is the aim of the present article to examine into views entertained by the authors of the above works on the subject of melancholia, and to compare them with those contained in the writings of older writers, as well as with opinions to be found scattered in the periodical literature of insanity. It is true, that the aim of the different writers named was different while writing their works. One class of them have had for their object to produce digested handbooks, others original and scientific treatises. While the one avoid discussion on disputed points, the others make such discussion an important part of their works.