Dror Wahrman’s Mr Collier’s Letter Racks: A Tale of Art & Illusion at the Threshold of the Modern Information Age bills itself as a piece of sleuthing that could only have been undertaken in the digital age. The late 17th-century Anglo-Dutch painter Edward Collier is uncovered as a master cryptographer, working on the cusp of the period’s information revolution, which was fuelled by an explosion in popular, ephemeral print. According to Wahrman: ‘Collier understood the full significance of these momentous changes and embedded in his work secret warnings about the inescapable slippages between author and print, meaning and text, viewer and canvas, perception and reality.’

This certainly is a good moment to rehabilitate illusionistic art – long dismissed by art historians as not art at all – and to give it the serious attention it deserves. Trompe l’oeil painting was all the rage in post-Restoration London, especially among the public figures and scientific virtuosi who