Although men professing special skill in certain operations, and doubtless possessing it, flourished in old times, and left more or less of their impress on the surgery of the present day, for that matter, it was not until the second half of the Nineteenth Century that regional surgery (which is what specialism virtually amounts to) was systematically cultivated. Now there is hardly a portion of the body to which practitioners who make its ailments a specialty do not direct their searching methods of examination or on which they do not practise their ingenious devices in the way of treatment. Specialism has always been decried by a large section of the medical profession. On the other hand, it has been and is still overrated by the laity. The true estimate lies between the two. The specialists have advanced surgery immensely, but, with many honorable exceptions, they have laid too much stress on their several specialties, making too wide a range of ailments fall within them. As for the community at large, their shortcoming lies in the fact that most of them would seek for a specialist in mumps in case that painful but transitory infliction were to come upon them, and in their underrating of the family physician. To change for a moment to a topic akin to the germ theory of disease, the reader may be reminded that the antitoxine treatment of infectious disease involves in almost every instance the use of some product contained in the serum (that is to say, the watery part of the blood). This leads to the subject of the use of natural and artificial serum in the treatment of disease. To quote again from the article entitled, "The Nineteenth Century in Medicine" ("New York Medical Journal," Dec. 29,1900): "It has been observed that the normal serum of certain animals that are insusceptible to particular infectious diseases, if injected into the human blood current or even into the subcutaneous tissue, confers more or less of immunity against those diseases.... Artificial serum seems to have been first employed by Edmund R. Peaslee as a benign application to the peritonaeum in the operation of ovariotomy. His conception of its mode of action is not very clear, but he was a very successful ovariotomist, and we can only conjecture that he builded better than he knew, like many another man. A few years ago much was expected from transfusion of blood, but gradually the conviction has forced itself upon us that it is wellnigh useless, and indeed that, on the whole, it is worse than useless. It has virtually been abandoned.... But experiments in transfusion have not been fruitless; they have culminated in demonstrating the inestimable value of infusions of 'normal,' or 'physiological,' solutions of sodium chloride, and not only of infusions, but also of peritoneal irrigation with such solutions. Many a life has been saved by resorting to this measure, even in apparently desperate cases."