WHAT WILL BECOME of biography when there are no more caches of handwritten letters for future generations to find, I wonder. This captivating family history, which paints a vivid tableau of Victorian and Edwardian life in the best circles, grew from a cache of letters - adoring, confiding, intimate, written from the heart, sometimes five a day - by the painter Sir Edward Burne-Jones to a married woman named May Gaskell.

May was the great-grandmother of Josceline Dimbleby, who has hitherto written only cookery books. The fact that this is her first foray into biography - a genre she regards as a scholarly preserve - gives the work a fresh, almost ingénue quality. When she steps into the Bodleian or the