On Bloomsday in 1948 Marshall McLuhan wrote Ezra Pound a letter in praise of the Pisan Cantos. It closed on a query about detective stories: 'I've been pondering your remark that the Cantos are a detective story. Should be glad of further clues from you. But one thing about crime fiction that I have noted may or may not be apropos here. Poe in 1840 or so invented the cinema via Dupin' (McLuhan to Pound, 16 June 1948, Lilly Library Pound mss. II, hereafter LLY mss. II). Here is McLuhan at his most McLuhanesque - nutty at first glance. His most famous claim of this type is his interpretation of the myth of Cadmus sowing the dragon's teeth, which spring up warriors fully armed, as the invention of the alphabet. (Why are dragon's teeth like letters of the alphabet? 'The phonetic alphabet was the greatest processor of men for military life that was known to antiquity.' [Understanding Media, hereafter UM, p. 72])

Dupin deals with a corpse as stil life. That is, by cinematic montage he reconstructs the crime, as all sleuths have since done. Are Cantos 1-40 a reconstruction of a crime? (LLY mss. II 16 June 1948)

By golly, he was right about Dupin's frame-by-frame reconstruction of the crime, though it may not be true that Poe invented the motion picture. The insight, McLuhan realised, was a terrific lead, which he returned to in a ...