Is the age of the book over? Chaucer’s Clerk of Oxenford dreamt of possessing 20 books – unique manuscripts that would have cost, in medieval England, about the same as three town houses. But in the five centuries between the invention of printing and the internet revolution, books as objects became steadily less precious, cheaper, nothing special.

Today it takes the iconoclasm of Cai Guo-Qiang, China’s Olympic pyrotechnic artist, to return a sense of danger and discovery to the book. After mixing gun-powder with paste to draw smoky, semi-abstract firework pictures reminiscent of calligraphic scroll painting, he placed a bundle of matches on a striking strip along the base of the spine of each volume in his limited edition “Danger Book”. A dangling string attached to the matches entices the reader to pull and ignite the pages.