A SOLITARY man, McPhee. He is the best journalist in America.

You could argue that. Knowing Washington, you would.

He does not write of the pleasures we take in, say, fettucine trifolati, or of the rococo assertion that "Panama Canal" really means something. And as one sprints through Byzantium, dining out on political intrigue, it soothes the conscience to know that someone is contemplating the verities.That's John McPhee.

"It rings some pretty deep atavistic bells with people," says McPhee. "It" is "Coming Into the Country," his 13th book in 12 years, which is about Alaska. It was serialized in The New Yorker, and it is a best seller, his first.

Alaska comes off sounding like the perfect American idyll: man solitary against nature and vice versa, Waldenesque, an old-fashioned yarn about a fierce frontier, grizzly bears, Kayaks, who's gonna get whom first. McPhee himself reads like the quintessential New Yorker writer. Persnickety, observant, bemused if not harrassed by women, urban life, writing. Like Eustace Tilley in a beard and down vest.Or, as a friend says, like one of Moby Dick's isolatoes.

Writing "My daughter has been badgering me," says McPhee, "because I only talk about how miserable, how awful, the wretched pit that it is. Joan Didion writes about "the low dread" she feels as she has to go down in there and write."

So perhaps that is why McPhee writes about survivors. He writes about people who stand wind-whipped on the mountain top, either staring into the abyss (which is crazy), or ignoring it (ditto). He writes about experts, people who know how far to stretch their minds and bodies, and find, in the stretching, that nothing else, no one else, no thing, is as consuming as the struggle with which one can, with luck, wrench feats from that balky, puny, imponderable beast, the self.

So over the years fans of McPhee are compelled to read of things Horatio never dreams of, of things one's friends never speak of.

About some wild man who makes birch-bark canoes. A 1968 tennis match between Arthur Ashe and Clark Graebner. Bill Bradley, the basketball player. Time spent on a lorn Scottish Hebrides island, looking for McPhee bones. David Brower, the environmentalist. Ted Taylor, designer of atom bombs. Frank Boyden, headmaster of Deerfield Academy. All are topics McPhee has covered since joining The New Yorker as staff writer 14 years ago.

Lonely people consumed by expertise.

"It's interesting what you're driving at," says McPhee. "The common chords. I'm usually described as someone who writes on a wide variety of subjects. They seem like such a scattered lot, the people I write about.

"That's also true of the people in Alaska. When I go there, I don't even want to come out, it's so consuming. There's a pretty big societal difference between Alaska and the rest of the U.S. There are plenty of people, my wife included, not as absorbed as I in it. They lead pared-down lives. Undistracted."

McPhee loves facts, interlards his conversation with them, is a quick study and lucid explicator of such esoteric fields as atom bombs, orange cultivation, aerodynamics and the paranoid caginess of art dealers. He writes about people who know many facts. But facts are not, alas, the whole truth.

People, in all their exasperating splendor, may not be the whole truth either, but it is people one keeps coming back to. "The sketching and building of character on a page," says McPhee, "is possible in a wider area than fiction.

"I write about character expressed through expertise," he says. "Take Ashe and Graebner. What's really interesting about those two is when people face each other in a situation like the semifinals at Forest Hills, then it becomes a struggle of character and psychology. The fact that they're experts interests me plenty, but how it forms the character is what I'm after. Character interests me more than technology!"

And so it doesn't matter, when quibbling about what really means something, that what McPhee writes about sounds like the Boy Scout handbook: "I lift my fish rod from the tines of a caribou rack . . ." One man's meat is another man's caribou rack. For years, McPhee's devoted cult of fans have been gnawing, like feral dogs, on whatever he dishes up.

Success is not likely to spoil someone whose sense of life's precariousness is as acute as McPhee's. Besides, he lives in Princeton, an oasis of rosy-patina brick and academic backbiting, amongst New Jersey's oil refineries. It is somewhat idyllic. In his garage, he keeps a canoe. Aluminum, alas. "There are millions of writers here," he says. "If you throw a stone you hit one. I used to play tennis with Peter ('Jaws') Benchley until my elbow went out. (I'm very evangelical and boring now about running and I will not talk about it, for your sake.) Princeton. If you want to be put perspective about best sellers, this is a great place to be."

McPhee was born in Princeton in 1931. He went to Princeton public school, Princeton. His office on Nassau Street is 50 yards from the office of the first Mrs. McPhee, a photographer. He and the second Mrs. McPhee, Yolanda, who runs a house plant business, live in a house he and his father built. He has eight children, including stepchildren. "I am the most provincial person you'll ever meet," he says. "The only thing that deprovincializes me is my work."

Carrying a reporter's notebook gives the shy an excuse to ask all the nosy-parker questions that occur to people who don't talk much and listen a lot. "I flunked kindergarten because of shyness," says McPhee. He turns off his office telephone. He has no agent. He never permits his photograph to appear on book jackets.

"I'm still shy," he says. He dedicated "Coming Into the Country" to his shyest child, Martha. "I always feel awkward and tongue-tied in the first interview with somebody," he says. "Doing something helps me get over it. Maybe that's why I'm attracted to experts. They're so occupied with what they're doing they don't pay any attention. That's part of it. Just part of it. Everything is too complex."

There's a fire going in the big country kitchen, which is cluttered with gourds, plants, shells, posters of the save-the-whales silk.Behind him, through the windows, an unmowed amber meadow, birch trees, glitter in the winter sun. One tries to get invisible, sink into the chair, drink coffee, put him at ease with lit-biz talk. He warms eventually.

Yesterday, there had been a 20-minute long-distance telephone monologue on the vagaries of New York-Princeton train schedules. At the beginning, McPhee - cordial but shrunken with anxiety - picks one up at the train station. It is clear that McPhee a.) loves train schedules and b.) can hardly bear interviews.

Fingernails bitten in anticipation of being caught out at one's own game were bitten in vain. John McPhee, the expert at scrutiny and method, holder of two National Book Award nominations, is appalled at the prospect of talking to strangers.

It begins, slowly, with Yolanda, red-checked, down-vested, seated nearby. There's a prickly attack on Tom Wolfe. There's characteristic angst over this phrase, "literature of face," which is the name of a seminar McPhee teaches at Princeton.

'Tom Wolfe's claim was that the novel and the novelist had had it, and the 'main event,' as he put it, was factual writing. Here's where it's at now in terms of literature and art. I just couldn't agree. For one thing, it's not new.It leaves out all writers who were doing this when Wolfe was in diapers. And when somebody publishes a novel called 'Falconer,' you don't say the novel's dead."

"Literature of fact" doesn't suit him either. "It's not my title," he says. "It was meant to suggest there are artistic possibilities to factual writing, that a piece of writing is a more complex thing than something to convey information."

McPhee very much fits the old "Front Page" ideal of reporting as shoe leather, guts, luck, an endless pedant's grind of information-gathering. He has never worked for a newspaper - whether through stubborness or sheer heroism. His ambition has always been to work for The New Yorker. His one other job has been at Time magazine. His friend and Boswell, William L. Howarth, writes that he started at Time in 1957 and "worked in 'the back of the book,' an area virtually unaffected by weekly news events."

No crisis mentality here. But McPhee says such things as "writing is such a lonely awful thing" and "I get my shoring up from Bob Bingham (an editor) at The New Yorker. I moan and groan at the water cooler." At Princeton - right, tight, little island that it is - McPhee speaks of running into Carlos Baker, the biographer of Hemmingway. Winsomely, Baker tells McPhee that he ought not to get too big a head, because he's been dealing, after all, with "a very thin wedge of a very large pie."

McPhee gazes into the middle distance. "I don't know if I need that," he says. "I don't have a lot of confidence. Too little." In short, when he says writing hurts, and then you hear about his scourage of a method, you believe him.

Howarth has chronicled the method in his introduction to "The John McPhee Reader" (a Washington best seller). First he says, McPhee types his notes, and can accumulate as many as 100 pages. He Xeroxes them, files the Xerox, binds the original, then reads the binder over and over again. He adds more typed notes of ideas, nuances and research.

Then he sketches the shape should take. Structure is one of McPhee's glories, a luxury ravishing to the hearts to harried daily journalists. "Structure ought naturally to come out of the material," McPhee says. So "Levels of the Game," for example, about Clark Graebner and Arthur Ashe in the 1968 semifinals at Forest Hills, become a series of quick-cut, tennis-inspired volleys.

McPhee then drafts a lead, which, sets the tone and motion of the story. He telephones it to The New Yorker offices in Manhattan.

Then he codes the binder, with topic titles for various story segments. He writes the titles on index cards. He shuffles the cards. Ponders them to determine the order of the story.After many agonies, he thumbtacks them in the order he determines to a large bulletin board.

Exhausted? Not McPhee. Relentless, he slogs on. He cuts the Xeroxed notes into "thousands of scraps," Howarth writes, ranging from one-line ribbons to paragraph chunks. He sorts them into folders, one for each index card. He files the folders in order of the cards. He stabs the first index card with a dart. He opens the corresponding folder. He arranges the scraps. Consults the train schedule perhaps.

And begins.

Those translucent palaces of logic he builds are the product not of genius but of scut-work.

Scut-work may be an attribute of genius, if you think of it a hunger for information and atttention to detail. Think of Da Vinci's notebooks, with anatomical drawings and blueprints for helicopters. Think of Jefferson's indisposition to keep his fingers out of any pie. He left 18,000 letters, Jefferson did.

Those two were Renaissance men. One does not necessarily imply that McPhee is of their company, only that there may be very little of the 20th century in John McPhee. There is, however, the tang (that delightful fellow Baker might say the smirch) of the New Journalism. McPhee covers events in which he participates, like his foraging trek with the late Euell Gibbons. He covers causes he advocates, nature and wilderness. He covers events he has on at least one occasion manufactured. He thought up the formula for "Encounters with the Archdruid" (which garnered one of the National Book Award nominations) before he found subjects for it. Then he met the environmentalist David Brower and cast him as antagonist. Then he drew up a list of 35 possible adversaries to introduce Brower to. The list was narrowed to three, and the A, B, C versus D formula that had sprung to McPhee's mind was incarnate.

"Levels of the Game," the saga of Ashe and Graebner, was McPhee's first multiple profile, the one in which the A versus B struggle became a formula and provided the structure, action and psychological motivation of the piece. With the Brower formula, says McPhee, "I got more ambitious and thought of three people to a fourth."

Finally, in the manner of the New Journalists, McPhee conveys his own sense of the situation - lyricism, wry, humor, and often, low dread. In Alaska, for example, he comtemplates a gouge on the shoreline of a river he is navagating. It might have been made by a grizzly, he writes, trying to save itself from drowning. "Who can say? Whatever the story might be, the pit is the sign that's trying to tell it."

It is McPhee's own world. "Such a stream of things happen!" he exclaims. "I could relate practically everything I write to things I was interested in from the ages of 10 to 22."

You could. You could also hint that McPhee, at 46, is somewhat trendily woodsy, tennis-elbowed, joggy, downily-vested, somewhat the breakfast autocrat, someone The New Yorker could, in fact, draw cartoons about. But McPhee makes it disarmingly clear that he never conceived of such a thing.His boyhood was, in fact, the prelude.

His father, the U.S. Olympic physician who attended Muhammad Ali, is now 82 and retired. He was the Princeton University athletes' doctor. Young McPhee played basketball, and with his father, who has summers off, went to canoe camp. "It went on well into college," says McPhee. "The place was well-imbued with what would now be called 'ecological awareness.' Not just trees and rocks, but now it all fit together."

Graduating a year early from high school, McPhee attended Deerfield Academy for a year before college. That became "The Headmaster," a profile of the indefatigable, sportif, immensely aged Frank L. Boyden.

McPhee was the whiz kid television panelist on "Twenty Questions," an early '50s game show, for the four years he was in college. "Fond of games . . . ," Howarth writes, "it taught him how to assemble facts and infer their hidden meanings." There was a year of study - and basketball - at Cambridge. Then it was back to Princeton.

A friend drew McPhee to Alaska, a friend who is a National park Service planner. By this time, one knows it is something else, too. McPhee is chattering by now, if a man who never splits an infinitive even in conversation, can be said to chatter. There's a hike through McPhee's amber meadow, a discussion of the Princeton area climax growth, a long frosty look at the birches.

He gets headaches looking at the Alaska sun, he writes. "The sun has been up 14 hours, and has hours to go before it sets."

There's an inspection of the aluminium, alas, canoe in McPhee' garage. "Terrific for portage," he says, commanding the photographer to heft one end.

His eyes are peeled, as though missing one detail, one naunce, one Alaska sun would make the truth die. Or the reader. Or the writer.

He goes on to speak of luck, of intergrity. Of Leon Crane, a graying aeronautics engineer, who is, says McPhee, the bravest and most resourceful man he ever met. He speals of Euell Gibbons. "Coming Into the Country" readers in taut prose the long, forced march of Leon Crane, who walked out of the wilderness in 50-below-zero weather. But McPhee likes to spin yarns, too. In conversation, he puts it this way.

"In Alaska, there was this guy, fell out of an airplane. What a story to tell! A scene and a half. It was a B24 bomber, an obvious liberator. We're talking Dec. 21 (1943), he comes out of an airplane. In March he gets to fairbanks and he didn't even have any mittens. Or a sleeping bag. His entire camping experience was one night as a Boy Scout in Valley Forge. Astonishing."

McPhee's own astonishing reporter's luck on locating Leon Crane after 35 years - his name was unknown even though his survival is a legend in Alaska - is also in the book, a trenchant, subtle undercurrent.

Euell Gibbons was another wilderness wanderer. McPhee went off with Gibbons into the woods to live on the land. "I was hungry as hell. We were eating only vegetation we'd foraged. On the seventh meal, we introduced salt. At the eighth meal, sugar.

"One day we ran across a pheasant which had been hit by a car. It was still fresh, warm as your leg. But we didn't eat it. I figured it would spoil the story. Sixteen meals we ate. The last one, we bought a steak in the supermarket and laid it out with all our wild greens. We both gained weight on that trip. November it was. Colder'n hell, I'll tell you." He smiles.

Then it was back to the Panama canal and Manhattan and thousands of Iranians either protesting or proclaiming the visit of their queen. One couldn't make it out. But it was snowing heavily. It was a blizzard, dizzy, blind-white, even through the silk-framed blinds of the 47th floor. That really meant something.

Now one stands in Nassau Street, trying to board a bus back through the oil refineries to Manhattan. McPhee is still talking. He gestures. He laughs. The bus waits. William L. waits, tagged up in running gear for the afternoon's jaunt with McPhee.

"People say what are you working on now? Holy God, I wish they wouldn't ask me that. An author is having a big time. A writer is having a miserable time. An author goes to plenty of parties. Basks in the sunlight. A writer has a miserable time. This attention acts as a king of friction which slows the momentum down. It's authoring.

"The struggle of character and psychology! Euell Gibbons's whole character was drawn into this. I'm just amazed that people can get through everyday Doesn't that amaze you every day? To know that you'll make through the next day?"