How, over half a century, did Prof. James Murray corral 414,825 words and 1,827,306 ''illustrative quotations'' into the 15,490 single-spaced pages of the first, 12-volume Oxford English Dictionary, ''the finest dictionary ever made in any language''? And how did Winchester wring a second great yarn out of the history of a reference book? His 1998 best-seller, ''The Professor and the Madman,'' a dual character study contrasting Murray with the lunatic who did invaluable OED legwork from his asylum cell, skimmed through some of the material here, but this is the fuller, more peculiarly inspiring account. And Winchester's involving and gregarious narration is nearly Dickensian. Even his footnotes twinkle.