Visual Humour - (J.R.) Clarke Looking at Laughter. Humor, Power, and Transgression in Roman Visual Culture, 100 B.C.–A.D. 250. Pp. xii + 322, ills, colour pls. Berkeley, Los Angeles and London: University of California Press, 2007. Cased, US$32.95. ISBN: 978-0-520-23733-9.