Having disposed of the original notions of the author of the ‘Encheiridium Anatomicum,’ in this first disquisition, Harvey, in his second, returns to his own views, which he proceeds still further to illustrate and confirm by additional arguments, observations, and experiments. In this admirable essay, we obtain innumerable glimpses of the clearness of Harvey’s judgment, of his admirable powers of observation, and the diligent and excellent use he made of them; we at the same time become aware of the great loss we have sustained through the destruction of his Medical Observations. Riolan, in his Encheiridium, proposed to point out in the structure of the healthy body the seats of the various diseases, and to discuss their nature in conformity with the opinions that had been entertained of them. This was obviously at once a barren and an impracticable route: the matters he had in hand could never have been other than abstractions, and his own observations criticisms on opinions, never on facts. How much more natural and judicious the course which Harvey proposes to himself, when he informs us that in his ‘Medical Anatomy’ he meant, “from the many dissections he had made of the bodies of persons worn out by serious and strange affections, to relate how and in what way the internal organs were changed in their situation, size, structure, figure, consistency, and other sensible qualities, from their natural forms and appearances, such as they are usually described by anatomists; and in what various and remarkable ways they were affected. For even as the dissection of healthy and well-constituted bodies contributes essentially to the advancement of philosophy and sound physiology, so does the inspection of diseased and cachectic subjects powerfully assist philosophical pathology.” This was precisely what Morgagni lived, in some considerable measure, to achieve, and it is that which it has been the business of modern pathology, through the illustrious line of the Baillies, Laennecs, Andrals, Louis, Cruveilhiers, Carswells, Richard Brights, and many others, to render more and more complete. Riolan never replied to Harvey; but neither did the Parisian Professor attempt to vindicate his views, nor did he exhibit such candour as to own himself otherwise convinced or converted. His doctrine had no abettors, and never bore fruit; it stood a barren ear amidst the lusty, green, and copious harvest, that had already sprung up and overspread the lands.