_The Constitutional Origin and Treatment of Local Diseases_--his principal work--in comparison with the vast mass of medical literature up to that time put forth, stands out in favourable relief. In it two great principles are laid down--that “local diseases are symptoms of a disordered constitution, not primary and independent maladies, and that they are to be cured by remedies calculated to make a salutary impression on the _general frame_, not by local treatment, nor by any mere manipulations of surgery.” This single principle changed the aspect of the entire field of surgery, and elevated it from a manual art into the rank of a science. And to this first principle he added a second, the range of which is, perhaps, less extensive, but the practical importance of which is scarcely inferior to that of the first--namely, that “this disordered state of the constitution either originates from, or is rigorously allied with, derangement of the stomach and bowels, and that it can only be reached by remedies which first exercise a curative influence upon these organs.” It will not detract from the merit of Abernethy to add to this account that his predecessor, Dr. Cheyne, and his contemporary, Dr. Lambe, have most satisfactorily and radically carried out into practice these just principles; or to remark that great public reputations ought not to be allowed, as too often is the fact, to overwhelm less known but not therefore less meritorious labours. As to _dietetics_, the theory of Abernethy seems to have been better than his practice. When reproached with the inconsistency that the reformed diet which he so forcibly commended to others he himself failed to follow, he is related to have used the well-known simile of the sign-post with his usual readiness of repartee. It was while Dr. Lambe was at the Aldersgate Street Dispensary that Abernethy formed the acquaintance of that unostentatious but true reformer--an acquaintance which was destined to have no unimportant influence upon the medical theories of the great surgeon. Abernethy was at that time writing his _Observations on Tumours_, and he had intrusted to his friend one of his cancer patients to be treated by the non-flesh and distilled water regimen. He carefully watched the effects, and he has thus given us the results of his observations:--