a veryar i, there was few number of blood transfusions wasormed, even though it obviously a very bloody war. but in world war two, the u.s. military really geared up -- world war ii, the u.s. military really geared up. they have the drive for written and the red drives to send american men overseas and in various theaters of war. driveshen were the blood in the united states? when did that start to be accepted by the general public? professor lederer: i would say during world war ii. , you had individuals -- sometimes there would be a radio announcement that there was a train wreck and they would need a lot of transfusions, and people would come to the hospital. innovations that allow blood to be stored for a longer time, and also for god to be separated into plasma and -- for blood to be separated into plasma and red blood cells. drives,mass of blood the blood for britain program, where again, more than 20,000 americans donated blood that was going to be sent to aid the british people during the war. while hospitals are during the first types of transplants? professor lederer: mass gen