Replica drills used by Dr T W Perry for experiments in neolithic trepanning. Made between 1930 and 1970. Trepanning drills have smooth wooden shafts and tips of very hard material, to cut into the bone as neatly as posible. The tip of the widest trepan (white in colour) is made from shark tooth, the other two have tips made of flint.
© Science Museum / Science & Society Picture Library