William Boyd’s 15th novel begins well enough. In 1894 Edinburgh, a 24-year-old piano tuner is promoted to the Paris branch of the firm he works for. Boyd is good on the inner workings of the piano: ‘the hammers, the rockers, the jacks, the whippens, the dampers — its innards were exposed like a clock with its back off or a railway engine dismantled in a repair shed.