When the system of medicine founded by Borelli was in vogue, called the "Iatro Mathematical," it would certainly have been acknowledged that a superabundance of fat, when developed in the human body, could interfere with the vital organs in the performance of their functions, and thus be the cause of much disturbance and of many diseases. But this would no longer have been admitted, when Broussais, the distinguished author of "Chronic Phlegmasia," in our own day, in harsh and severe language, and with an air of conviction, loudly proclaimed that all disease resulted from local irritation, whence it was irradiated throughout the organism, as in the case when a sharp instrument pierces the flesh. This theory was the very opposite to the teachings of the majority of medical men of a previous age, who maintained that local disease resulted from a general disturbance of the whole system. Thus, if the stomach were affected, Broussais called the disease a gastritis (or inflammation of the stomach), which might induce disturbance of the system at large; while many of the old school would have said that if the stomach were especially diseased, it was because nature chose that channel in order to eliminate from the body the morbid principle which in the outset had attacked the entire system. It belongs not to the subject on hand to endeavour to signalize all the errors of the old school, nor to set forth what truth there may be in the system; but I would ask one simple question. It has happened to every medical practitioner to be called in to see a person recently taken ill, and that he has said, "The disease is not yet well characterized; by-and-bye, or to-morrow, I shall be able to form an opinion, and say what the disease is." But until this "by-and-bye," until this "to-morrow," what happens to the patient? for it is evident that there is sickness, a general ailment. And when one particular portion of the body, an organ, is principally affected, when the disease has there manifested itself, as we say, shall we be far wrong in saying that it is a kind of crisis? It would be just what happens, only more evidently, in those fevers which terminate in a critical abscess.