The empty chairs belonged, all too briefly, to the doomed young First World War airmen who failed to return from the terrifying daily aerial combats above the trenches of the Western Front. The edict of their commander-in-chief was the missing aviators were to be immediately replaced. Before the new faces could arrive, the departed men's vacant seats at the squadron dinner table were sometimes poignantly occupied by their caps and boots, placed there in a sad ritual by their surviving...