Edward Jenner humans a cowpox vaccine against smallpox. For example, Dorset farmer Benjamin Jesty successfully vaccinated and presumably induced immunity with cowpox in his wife and two children during a smallpox epidemic in 1774, but it was not until Jenner's work that the procedure became widely understood. Jenner may have been aware of Jesty's procedures and success. A similar observation had also been made in France by Jacques Antoine Rabaut-Pommier in 1780. Noting the common observation that milkmaids were generally immune to smallpox, Jenner postulated that the pus in the blisters that milkmaids received from cowpox (a disease similar to smallpox, but
Edward Jenner of nestling birds in general." Jenner's nephew assisted in the study. He was born on 30 June 1737. Jenner's understanding of the cuckoo's behaviour was not entirely believed until the artist Jemima Blackburn, a keen observer of bird life, saw a blind nestling pushing out a host's egg. Her description and illustration of this were enough to convince Charles Darwin to revise a later edition of "On the Origin of Species". Jenner married Catherine Kingscote (died 1815 from tuberculosis) in March 1788. He might have met her while he and other fellows were experimenting with balloons. Jenner's trial balloon descended