The transfusion of blood has been rightfully considered a major procedure. This circumstance is due to the facts that first, the operation, until very recently, was done only in the greatest emergency; second, the technical details could be mastered only after repeated trials; third, when not done properly and carefully in every detail, the operation often proved fatal.
From time to time, the methods have been simplified until, at present, the physician is told that he may collect a quantity of blood from the donor, and after adding a small quantity of sodium citrate solution, he may carry it from his office to the hospital and inject the modified blood into the vein of the recipient. This method, which is said to have given good results in the hands of some men, is open to serious objection. It would seem to me that the most rational procedure would be the