There is something especially poignant about Rex Whistler’s paint box that was left at Plas Newydd: he never returned to use it again. On the day war broke out he was at Mottisfont painting a trompe-l’oeil. Almost invisibly high on the wall are the words: ‘I was painting this ermine curtain when Britain declared war on the Nazi tyrants. Sunday September 3rd. RW.’