For many years James Lees-Milne had the enviable job of going about Britain looking at historic houses, and the ticklish job of dealing with their owners--who might have to be cajoled into deeding their property to L-M's employer, the Historic Trust, or told that the Trust wouldn't take their ugly, over-restored house as a gift. Gentry himself, he spent his off-hours--hardly distinguishable here--in a haze of Mitfords, Pope-Hennessys, and Sackville-Wests; took tea regularly with ""upright, starchy, forthright"" Ivy Compton-Burnett; and heard the news from Harold Nicolson. Everybody, of course, had Churchill stories. For it was also wartime, and what these diaries record (Ancestral Voices covers 1942 and 1943; Prophesying Peace continues to war's end) is Britannic majesty, about to fall, at its unassuming best and its idle worst. On the great estates, where evacuees are sheltered and American troops are billeted, the owners cope eccentrically and cheerily, and make over their unmaintanable properties to the Trust for postwar preservation. (Pragmatic GBS, however, advises a loose arrangement whereby, should his name be forgotten, the Trust could reap the benefit of selling his house.) Among L-M's London set, on the other hand, the war is an ambiguous affront (once pro-Hitler, they're now anti-Bolshevik); talk runs to salacious, cross-sexual gossip and grousing about the conduct of the war; and no one, certainly not Lees-Milne, looks forward to the future. But as a diarist he succeeds by setting down everything--the trivial and the momentous--and infusing it, through precise observation, with his own feelings. A historic bridge, disfigured with the names of Canadian soldiers, seems to him, prospectively, ""an interesting memorial. . . like Byron's name on the temple at Sunium."" His diary, too, is likely to be of greatest interest to history and posterity; but its vitality--coupled with its odd, chance findings--commends it to choosy readers today.