His perceptivity, naturally rapid, was evidently employed in observing the bearing of this axiom on the facts of disease. The digestive organs, which, if we extend the meaning to all those engaged in assimilating our food, compose nearly the whole viscera of the body, could not escape his attention, nor indeed fail to be regarded in all experimental investigations of any _one organ_. Accordingly, in his paper on the skin and lungs, we have seen a very important application of the relations between organs engaged in concurrent functions; we have placed before us the physiological evidences of their being engaged in a common function, and the sympathetic association it rendered necessary; whence he had observed relations of great moment, and pointed out the practical bearing they _must_ have on Consumption. He had, however, been paying attention for some time to the digestive functions, when his intimate friend, Mr. Boodle, of Ongar in Essex, gave a fresh stimulus to his exertions. This gentleman requested him to investigate the functions and conditions of the liver in various nervous diseases, as also in certain affections of the lungs, which had appeared to him, Mr. Boodle, to originate in the former organ. Mr. Abernethy says: "I soon perceived that the subject was of the highest consequence in the practice _of surgery_; for local diseases disturb the functions of the digestive organs, and, conversely, a deranged state of those organs, either occurring in consequence of such sympathy, or _existing previously_, materially affects the progress of _local complaints_."