The hash oils made in the 19th century were made from hand collected hashish called charas and kief. The term hash oil was hashish that had been dissolved or infused into a vegetable oil for use in preparing foods for oral administration. Efforts to isolate the active ingredient in cannabis were well documented in the 19th century, and cannabis extracts and tinctures of cannabis were included in the British Pharmacopoeia and the United States Pharmacopoeia. These solvent extracts were termed cannabin (1845), cannabindon, cannabinine, crude cannabinol and cannabinol.