Edward Jenner full-blown infection. Later, he injected Phipps with variolous material, the routine method of immunization at that time. No disease followed. The boy was later challenged with variolous material and again showed no sign of infection. Donald Hopkins has written, "Jenner's unique contribution was not that he inoculated a few persons with cowpox, but that he then proved [by subsequent challenges] that they were immune to smallpox. Moreover, he demonstrated that the protective cowpox pus could be effectively inoculated from person to person, not just directly from cattle. Jenner successfully tested his hypothesis on 23 additional subjects. Jenner continued his research
Caitlyn Jenner the pole vault, when Jenner took the lead, and javelin. By that point, victory was virtually assured, but it remained to be seen by how much Jenner would improve the record. In the final event—the 1500 meters, which was seen live on national television—Jenner looked content to finish the long competition. Jenner sprinted the last lap, making up a 50-meter deficit and nearly catching the event favorite, Soviet Leonid Litvinenko, who was already well out of contention for the gold medal, but whose personal best had been eight seconds better than Jenner's personal best before the race. Jenner set a