The progress and results of blood transfusion at this clinic, first with the Unger1 apparatus and then with my modification2 of the Unger apparatus, have previously been discussed in part by Dr. Blain and me.3 With these two types of apparatus, which were somewhat similar, nearly 2,500 transfusions of unmodified blood have been performed. The method has proved satisfactory and leaves little to be desired. The method provides for a continuous flow of blood from the donor to the recipient with scarcely any clotting, because stagnation is eliminated. The maximum of speed is acquired, the time necessary for the actual transfusion of 500 cc. being about five minutes. Many of the transfusions have required even less time, and it has never been observed that the blood was given too rapidly. Foreign material is not introduced during the transfusion, with the exception of 3 or 4 cc. of