Serge Voronoff (1866-1951), Russian-French physician. Voronoff is famous for his 1920 experiments where he transplanted monkey testicle tissue into human males. Three years later, in 1923, he presented his work to the International Congress of Surgeons in London, England, claiming that his transplantations had rejuvenated old men. He presented films that showed old and decrepit men regaining athletic abilities after their operations. Voronoff's future plans included the building of a park in Africa to breed monkeys for transplant material. This photograph is from the Bain News Service, one of the USA's earliest news picture libraries. The photographs date from the 1890s to the 1930s.