© Science Museum / Science & Society Picture Library
A trephine is a crown saw used for perforating the skull and removing a circle of tisue or bone. Trephination as a therapeutic or magico-religious procedure dates back to Neolithic times, with trephines (or 'trepans') often used as a method of releasing evil spirits from the patient. Over the centuries, this surgical procedure continued to be used to treat a variety of symptoms, from migraine to mental illnes. Dimensions: length 208mm; diameter 50mm; width 70mm.