Frederick Banting upon the idea of obtaining insulin from the fetal pancreas. He removed the pancreases from fetal calves at a William Davies slaughterhouse and found the extracts to be just as potent as those extracted from the dog pancreases. By December 1921, he had also succeeded in extracting insulin from the adult pancreas. Pork and beef would remain the primary commercial sources of insulin until they were replaced by genetically-engineered bacteria in the late 20th century. In spring of 1922, Banting established a private practice in Toronto and began to treat diabetic patients. His first American patient was Elizabeth Hughes Gossett,
Banting (crater) moon, which constantly faces Earth because of its tidally locked orbit. This makes Sir Frederick’s crater fairly central, since Mare Serenitatis is so easily viewed. Despite its location, Banting is a very small crater and can be difficult to see. A telescope must be used, and viewing during certain lunar phases is crucial to seeing such small craters, as well. It is recommended that, while it is waxing, the moon be viewed around the time of its first quarter; while it is waning, it should be viewed just before its last quarter. Craters may also be conspicuous during a gibbous