Peat is a thick, damp mass of partially carbonized organic material that since prehistoric times has been cut out of bogs or moors in northern Europe, dried, and burned for fuel. For centuries, it has also been essential to the making of malt whisky—peat smoke both drying and flavoring the malt before it is fermented. (The main constituent of Islay peat is sphagnum moss, but it also contains traces of decomposed seaweed, heather roots, and salt grass—and faint echoes of these elements end up in the whisky.) A peat cutter first digs a drainage channel, then sections off a block of land into neat elongated rectangles with a triangular-bladed turf spade. One afternoon, off the road between Bowmore and the Islay airport, I watched Norrie Campbell—widely considered to be the best peat cutter on the island—finish the process, wielding his sharp, long-bladed turf spade with balletic grace and athletic strength, cutting perfect ingots of sodden, 7,000-year-old matter and tossing them up onto the peat bank as easily as if they were bundles of feathers. Campbell, stocky and weather-chafed, with long whitish hair and an impish grin, looks the quintessential Scottish rustic. ''Well, yes,'' Jim McEwan agreed as we drove away from the peat moor, ''but, you know, Norrie's also the man who introduced disco to Islay.''