WE ARE ALL entitled to a degree of fidelity from those on whom we lavish our affections and attention, and so it is heartbreaking when we discover they have been playing fast and loose with a rival. It's particularly bad for biographers: John and Mary Gribbin, who had presumably established a comfortable mtnage 1 trois with the dashing Robert FitzRoy, must have been sadly disappointed to find him cuddling up with Peter Nichols on the side. Not even FitzRoy's most ardent supporter could pretend he was any more than a minor character in the pageant of the nineteenth century: to have two biographies of him at the same time is truly an embarrassment of riches.

However, FitzRoy's is a story of astonishing courage, of nepotism and finagling, and of the noblest of intentions gone horribly wrong. He was one of those exaggerated, bombastic characters in whom boys' comics and the armed services delight (imagine Sir Ranulph Fiennes, Lord Archer and Mary Whitehouse inhabiting a single