One of the prerequisites for playing chess well is to have a decent feel for the geometry of the board. In today’s column, GM Jon Speelman explores this theme through a couple of somewhat unusual patterns the staircase and the stairwell. He also looks at a game by Will Watson, a player once described by Boris Spassky as “a drunk with a machine gun”. | Pictured: ‘Relativity’ by M. C. Escher