...according to Ovid the "right molar of a small crocodile worn as an amulet guarantees erection in men".
Not just any crocodile molar, evidently, but the one on the right. How did the ancients come up with some of this stuff?
The other link from Arts & Letters is to an extract from the book itself, from which one can read a little about early experiments in testicular transplant:
I am sure I have heard of experiments with ground up animal testes before, but I don't recall reading about whole chimp testes bit.The first experiment in grafting an entire testicle was performed by Dr. G. Frank Lydston on himself, on January 16, 1914. Expressing his disappointment that vulgar prejudices heretofore had prevented the exploitation of the sex glands of the dead, Lydston coolly reported how he transplanted into his own scrotum a suicide victim’s testicle. [p. 186]
L. L. Stanley, resident physician of the California state prison in San Quentin, reported in 1922 that he had first implanted testicles from executed convicts and then moved on to inject into his subjects via a dental syringe solutions of goat, ram, boar, and deer testicles. Altogether he made 1000 injections into 656 men. Stanley had been inspired by work of Serge Voronoff, an eminent Russian-born medical scientist working at the Collége de France. Voronoff in 1919 scandalized many by transplanting the testes of chimpanzees into men. He asserted that “marked psychical and sexual excitation” typically resulted, followed by a resurgence of memory, energy and “genital functions.” [pp. 186-7]
I guess there was little resembling ethics committees in those days.