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 Highest and best use Highest and best use, or highest or best use (HBU), is a concept that originated with early economists such as Irving Fisher (1867-1947), who conceptualized the idea of maximum productivity. One of the earliest citations of the term is found in the Minutes of the Maine Legislature as early as 1831 in speaking about the assessment and valuation of real estate: "..."the land was classified preceding such change of use, had such real estate been assessed at its highest and best use"..." It is the concept in real estate appraisal that shows how the highest value