"In April 1821, a medical gentleman in Edinburgh, aided by a landscape painter, fashioned a turnip into the nearest resemblance to a human skull which their combined skill and ingenuity could produce. They had a cast made from it, and sent it to Mr G. Combe, requesting his observations on the mental talents and dispositions which it indicated ; adding, that it was a cast from the skull of a person of an uncommon character..." - The History of Phrenology on the Web.
