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 would not fit on a site; therefore, that use would fail the physical possibility test. The highest and best use of a property must be financially feasible: the proposed use of a property must generate adequate revenue to justify the costs of construction plus a profit for the developer. In the case of an improved property, with obvious remaining economic life, the question of financial feasibility is somewhat irrelevant. In the case of an improved property with limited remaining economic life, the question of financial feasibility becomes a question of the maximally productive use of the site. If the value