The Widening StainFor the staff of the library at the center of The Widening Stain, it's easy enough to dismiss the death of a woman who fell from a rolling ladder as nothing more than an unfortunate accident. It's more difficult, however, to explain away the strangled corpse of a man found inside a locked room, surrounded by rare and obscure erotica. And that's not alla valuable manuscript has vanished from the stacks, which means that both a killer and a thief are