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,
Highest and best use reasonably probable and legal use of vacant land or an improved property that is physically possible, appropriately supported, financially feasible, and that results in the highest value. The four criteria the highest and best use must meet are legal permissibility, physical possibility, financial feasibility, and maximum productivity. Alternatively, the probable use of land or improved property – specific with respect to the user and timing of the use – that is adequately supported and results in the highest present value.". In some cases, a proposed use might be the highest and best use but for some cost that changes the