Experiments of blood transfusions between animals occurred as early as 1665. In 1818, Dr James Blundell (1790-1878) performed the first successful human blood transfusion. The largest number of successful blood transfusions were performed in Scotland from 1885 to 1892. Blood groups (O, A, and B) were discovered in 1902. Bloodletting in the United States was recommended as treatment for several diseases as recently as the 1920s. (An internet search does not show anyone named Max Richter associated with blood transfusions.)