Modern St andrews is overrun by golfers and international students, and its photogenic ruins attract large numbers of tourist snappers in this digital age. Robert Crawford s latest book reminds us that it wasn t always so. In the 19th century St andrews struggled to attract students and its ruins were seen by some (including Dr Johnson in the preceding century) as symbols of the town s decay. There were few golfers and the links saw the passage of strolling thinkers as well as frantic hackers.  One of these thinkers was Sir David Brewster, inventor of the kaleidoscope, conceived as a matter of physics and optics but eventually marketed as a toy. His interests expanded into the  natural magic  of photography and intersected with the investigations into  the art of fixing the shadow  already being conducted by Englishman William Talbot.  Brewster found common ground with local photographer John adamson, brother of Robert, who formed the famous co-operative with David Octavius Hill, and St andrews Provost Hugh Lyon Playfair, who struggled with Brewster to perfect the use of Talbot s new calotypes. The  Lit an