To the Editor: I settled in Monday evening for a read-through of the 125th anniversary issue (Oct. 24), expecting the usual slog, though a bit longer than usual (I didn't finish until Tuesday afternoon). Pleasantly surprised to find a sampling of features and reviews across the Book Review's lifespan, I made my way through with the usual combination of smiles at well-turned phrases, shrugs at boring passages, annoyance at what I considered ill-considered opinions and chuckles at well-placed bons mots. I was nearing the end when I reached Page 54 and the late Neil Sheehan's essay on the question of American war crimes in Vietnam, which was originally published not long before The Times's publication of the Pentagon Papers after a long legal battle with the ever-stonewalling Nixon administration, an achievement in which Sheehan was instrumental. Too young to have the read the piece when it first published, I was rapt and impressed by its unfading relevance more than half a century after it first ran. I don't usually hold on to anniversary issues, but Sheehan's essay and its timelessness made this a permanent keeper.