Swiss-born physician, chemist and alchemist Paracelsus noted how sweet vitriol [ether] "...quiets all suffering without any harm and relieves all pain, and quenches all fevers, and prevents complications in all disease."
Paracelsus was not impressed by the received scholastic wisdom of his era. A wandering student, he allegedly attended the universities of Basel, Tübingen, Vienna, Wittenberg, Leipzig, Heidelberg, and Cologne. “The universities do not teach all things,” he wrote, “so a doctor must seek out old wives, gipsies, sorcerers, wandering tribes, old robbers, and such outlaws and take lessons from them. A doctor must be a traveller... Knowledge is experience.”
Paracelsus observed that chickens enjoy sweet vitriol [ether] - after which they "undergo prolonged sleep, awake unharmed". Yet he did not extend this discovery from farm animals to people. For human consumption, Paracelsus concocted laudanum, an alcoholic tincture of opium with many added extras.