Uncommon Carriers is about the truckers, dispatchers, towboat crews, train drivers and trainee sea-captains whose lives revolve around shifting freight. There's a scene in the book in which a boatman goes up to the end of a towboat on the Illinois river. Halfway down he looks tiny; by the time he's reached the bow, he's an ant. The tow, pushing seven barges wired together, is much longer than the Titanic; it burns 2,400 gallons of diesel fuel a day. It is a distant relative of the mining trucks McPhee sees in the Powder River Basin in Wyoming, where the coal is sawed out of the ground to make canyons several miles long, and hauled to the coal trains by vehicles so large, he writes, that their tires look "the way bagels would look to a virus." Some of this coal goes 1,800 miles to Georgia's Plant Scherer, the largest coal-fired power plant in the western hemisphere. If it burns more coal in summer than winter -- that's for air-conditioning.

This is also a book about people dwarfed by their surroundings -- by the systems they operate, the machinery they drive, the distances they cover. Dwarfed -- but not necessarily diminished. Ainsworth, for instance, owns his own rig: a dark sapphire tractor and a chemical tanker so shiny and mirror-bright that you could part your hair in it. He reads the Wall Street Journal, collects boots and is something of a philosopher. When he has the exterior of his rig washed, he goes to places that use "either reverse-osmosis or deionized rinse water"; it costs him double, but there are no streaks on the finish. "This," he says, "is as close as a man will ever know what it feels like to be a really gorgeous woman." After he washes the interior of his tanker, he's free to pick up another load of hazmats. They are chemicals such as WD-40 concentrate, parts degreaser, surfactant, a soap used in making bricks, weed killers, paint thinners, latex for plywood, latex for the dye that turns brown cardboard white -- things you never knew existed. He won't carry cashew-nutshell oil, which goes into anything that requires friction, such as brake pads. "I believe it harms my barrel," he says. Ainsworth is a very, very good driver.

Like Ainsworth -- indeed, like most of the experts he encounters -- McPhee is also very good at what he does. He has written about geology in the past, and he deals with this stratum of American civilization in a deceptively neutral tone, as if he were describing tectonic plates: His prose has a tendency to stack up and roll on by like a two-mile boxcar railroad engine passing an impatient four-wheeler at a crossing.

What fascinates McPhee, apart from the lives of the men and women he meets, is their oddly coded language. He likes that hard-crust jargon, with its acronyms and labels, not least, I think, because it reflects the dignified efforts of men and women to encompass and express facets of an alien world much larger than ourselves. Very gently, and without any superfluous comment, McPhee portrays ours as a Rabelaisian economy, a web of bloated, fundamentally brainless systems ingeniously devised to serve the world's appetites. One moment it's coal; the next, it's those lobsters I mentioned, who are kept alive at a steady temperature to prevent them from wanting to molt and are sold all year round, all over the world, via the UPS hub in Kentucky -- a hub maintained by drowsy students who work nights to pay for college.

McPhee's uncommon carriers are, in their way, witness to the wilderness that is America, even to this day. In this absorbing and deceptively simple book, he goes back to Thoreau, paddling his way up a river that has already been worked over and abandoned by economic man; but I found myself thinking about the Lewis and Clark expedition and the moment when America was still a vast unknown. What has become of this humongous space? What's in it? Not mammoths, as Jefferson might have guessed. Just torpid lobsters, sleepy people.

Reviewed by Jason Goodwin
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