"I am no phrenologist, not knowing one organ from another, but I thought the skull of that wretched man no study"

Phrenology, a pseudoscience developed in 1796 by the German physician Franz Joseph Gall, was extremely popular at the beginning of the 19th century. Drawing on the assumption that different parts of the brain correspond to different mental faculties, phrenologists believed that personal characteristics could be deduced from the shape of the skull. Hogg clearly has a better grasp of the art than the Editor: a protuberant area above the ear is a sign of destructiveness believed to be particularly prominent in murderers.