Some 35 years ago I visited the National Gallery of Sicily in Palermo on the hunt for the ‘Virgin Annunciate’ by Antonello da Messina, the painter of the beautiful ‘St Jerome in his Study’ in the National Gallery in London. It was hard enough to persuade anyone that the gallery was meant to be open, and what staff there seemed to be about (a couple of deeply suspicious museum guards) had clearly dedicated their lives to saving the gallery’s electricity, rationing us in a succession of deserted rooms to a few seconds in front of any one painting, before plunging...