mixes the blood with the citrate by gently swinging it. If a properly adjusted tourniquet is kept on the donor’s arm while he works his forearm muscles by clasping and unclasping his hand, a flow of blood is obtained which is fast enough to prevent clotting in the needle, and indeed is quite as fast as most donors can tolerate. Blood up to 1,000 cc. may be collected in this way in ten to twenty minutes. If the vein be of a good size, it makes no difference whether the needle be inserted towards the heart or away from it. When enough blood has been collected, the tourniquet is removed, the needle is withdrawn, and pressure is maintained with a sterile swab over the site of puncture for a few minutes. No further bleeding will take place after this, and no suture is needed. The donor’s part in the operation is then finished. He should be made to lie on his back for a few hours afterwards, and given plenty of fluids, but beyond this no special precautions are necessary. When the blood has been drawn, and has been satisfactorily mixed with the citrate, the flask may be put on one side until it is wanted, its mouth having been closed with a cotton-wool stopper. If the blood is wanted at once, the flask may be stood in a basin of warm water to keep it at body temperature. Otherwise it may be allowed to cool, and can be warmed up again when it is to be administered. The citrated blood may be kept for a considerable time without undergoing any appreciable change in its therapeutic value. It has been given twelve hours or more after being taken with the same good effects as if it had been newly drawn. During the war advantage was taken of this fact to anticipate during quiet times the necessity for many transfusions during times of stress. The blood was drawn in some quantity and kept for several hours in an ice chest, so that it was readily available during the expected battle. Recently I have administered to a woman who had been operated upon for a ruptured ectopic gestation 600 cc. of citrated blood which had been kept for twenty-seven hours at room temperature after it was drawn. The effect was in every way as satisfactory as if it had been freshly drawn, and there was no sign of any toxic reaction. So far as I know, blood had not ever been kept so long as this before being used, but there does not seem to be any objection to so doing.