744 pp., $15.

ON THE ROAD from Middlebury College up to the Breadloaf Mountain campus (where in late summer a gang of artist types and their students celebrate the annual writers' conference started about 50 years ago by Robert Frost), you pass first through the scenic village of Ripton, Vermont, a town which will probably satisfy your expectations of what Robert Frost's home town should look like, You find little more than a post office, a phone booth and a combination gas station and general store dealing in two-for-a-penny-candy, dusty bottles of aspirin, applejack, Vermont cheese (kept under the moldy wooden bowl, and cheap), woolen socks, fishing tackle, and peanuts from a chipped enamel peanut roaster apparently left over from the Big-Top Circus days.

You then pass by one of those brown wooden national landmark signs indicating the proximity of the cabin where Robert Frost lived. Picnic tables and litter bins help commemorate the entrance to the road. Stopping to read the sign, you feel like a reverent tourist at Lexington and Concord or the Statue of Liberty. At the end of the dirt road which climbs about a mile through the woods toward the advertised cabin, there is still another engraved plaque. There, through a hedge and over another bank, an orchard of dwarf apple trees conceals (except from the annual busloads of DAR chapters and Leagues of Women Voters) the much announced Frost Cabin-unpainted, compact, reassuringly meager. Inside, the cabin is absolutely sparse but quite complete; a sitting room with fireplace and bookshelves, a tiny kitchen with saucepans and brillo pads, and a bedroom with a long workbench.

IT WAS SUNDAY afternoon and raining; in Vermont the foliage of the swamp maples and sumac had already turned their final colors. I sat in the rocker where Frost must have sat, before a fire leaping in the fireplace, enjoying the comfortable associations that I used to have with Frost. That was before Lawrence Thompson's just-published heavy second volume of Frost's biography, Years of Triumph. With it a whole summer's worth of enraged reviews have emerged, suggesting that Thompson had written an expose which profaned a sacred image.

Reading years of Triumph, I find Frost's image not so much profaned, or de-popularized. It was, for the reader, simply confused. The Thompson biography approaches Frost not with the reverence that one might treat a national monument but with the candor and objectivity that a literary topic merits. In 1939 Frost invited Lawrence Thompson, then curator of books at Princeton, to be his official biographer. Frost died in 1963 and the next year Thompson published Selected Letters in which it begins to be clear that the feelings between Frost and Thompson were not all pure affection and admiration. Four years ago Thompson finished the first volume (The Early Years) of his Definitive Biography, and this August the second installment appeared.

Years of Triumph covers the early years of Frost's fame in England and the United States, up to the death of his wife in 1938. It describes without malice or apparent prejudice several incidents which indicate that Frost was not a benign simple rustic writing pure-hearted doggerel, but rather an impatient, frequently lazy, hyperbolic man. The reviewers were furious. Some treated the book as a personal insult. One almost-yellow journal reduced its reaction to a sixteen-point print blare, "A good poet-but a very bad man."

I find Lawrence Thompson neither the cynical lip-smacking of one doing an expose nor the pretensions of a psychoanalyst. He shows no moral distaste for his subject. Thompson (with the equivalent of a straight face) describes events which reveal Frost to be not Santa Claus, not Albert Schweitzer, not America's favorite nostalgia-evoking bumpkin, but a modern man with popular modern dilemmas such as neurosis, guilt and ambition. We see him terrified of ruin and failure, compensating for his fear with self-aggrandizement, exploitation of friends, and uncompromising demands on his family. Frankly, I'm almost relieved. Somehow I can take Frost more seriously now; he seems put in the same critical boat with Pound, Eliot, and Stevens, confronting problems of real life instead of simply chopping wood and milking the cows.

I FIND FROST'S weaknesses less treacherous, actually, than the slow pace of Thompson's book. A shorter biography would be sufficient. Thompson seems to be compulsive about making his book complete, and thus reports scores of facts which seem to have no precedent, no consequence and usually, no interest. Perhaps Thompson is simply a businesslike writer: meticulous scholars should find no fault with his book, but for the average reader it is tedious and wearying. I have the feeling that many readers went through the book in the spirit of somewhat avaricious voyeurism, searching for expose. Otherwise I honestly cannot see why so much energy has been spent with the book.