In the 1920s and 1930s blood typing had come into its own, but there were limited ways to store blood once it was out of the body. The best way to keep people alive was to use other people as "blood on the hoof" — volunteers ready to donate blood at a moment's notice.
Percy Lane Oliver was a wannabe doctor. A very intelligent man, who won scholarships and passed tests, he was still shut out by the clannish medical community. Forced out of medicine professionally, he went into it as a volunteer. During World War I, he and his wife managed refugee hospitals for the Red Cross. At the hospitals, he saw the horror and the waste that comes with war, and the limits of medicine in ameliorating either of them.
After the war, he continued serving the Red Cross, which is how, one day, he got a call informing him that a patient needed a relatively new procedure called a blood transfusion. The practice had only started fourteen years before, and wasn't performed on more than a handful of patients before 1915. During World War I, doctors had found certain ways to store blood, but the supply, demand, and equipment at different hospitals was such that many hospitals needed donors to basically sit next to patients during the blood transfer. Oliver rounded up some friends and they all rushed to the hospital. A volunteer nurse was found to be the match, and gave the necessary blood.
Upon being informed that not all patients were lucky enough to get blood, Oliver started a movement meant to remedy the situation. He wanted to get a panel of people together who would volunteer to be "blood on the hoof." In the first year, he had four volunteers. They received one call. By their sixth year they had four hundred people and seven hundred calls. By the end of the 1930s, the "panel" had grown to thousands of members, supported by staff and resources provided by the Red Cross, and responded to 9,000 calls per year.
Oliver had, in a couple of decades, saved thousands of lives. When blood storage improved, he dismantled his panel, but still made himself useful. He toured the nation encouraging people to donate blood until his death in 1944.
Image: National Archive, Quebec