Then, in late 1920, in one of the happiest but most improbable episodes in the history of scientific progress, a struggling young general practitioner in London, Ontario, read an article about the pancreas in a medical journal and got an idea for how he might effect a cure. His name was Frederick Banting, and he knew so little about diabetes that he misspelled it as “diabetus” in his notes. He had no experience of medical research, but
