Not Just Another Pastel Coyote : AN ELEGY FOR SEPTEMBER, <i> By John Nichols (Henry Holt: $18.95; 161 pp.)</i>

About a year ago, while a bunch of us sipped beer on the porch of a hotel in the Rockies, John Nichols played guitar and dipped into his endless stock of blues songs. He had just delivered a veritable sermon on the ecological consequences of squandering liquid dishwashing soap. He was then, and is today, a man with many opinions, the type of person who gets out of bed every morning ready to fire off a letter to the editor, a kind of amiable nag. But he is also a lover of the mountains, a smiling singer of songs.

Sometimes his novels read like a boxing match between these two aspects of his personality, but the important fact is that John Nichols has built a singular and impressive career on considering what the Southwest is about and should be about. He has cut his own trail in a region where most seem content to amble from one pastel coyote to the next. And now he has delivered “An Elegy for September,” a departure from his earlier work in which people were often pounding their fists and yelling about issues. This book focuses on what it feels like to be alive and what is so terribly sad about maybe dying.

This book tells us:

“He was light-headed and floating in a strange euphoria. I’m almost helpless (he thought), surrounded by a billion trees and many wild animals in the middle of nowhere. How silly. I really don’t know why we do things, but we do them, and persistence is remarkable. And in the next moment my heart--

“Suddenly, he had a terrible longing to make love with the girl again and promise her everything.”

When the letters from a 19-year-old woman begin to arrive, the narrator is a 50-year-old writer with a bad heart going through his second divorce. He is intrigued, answers, and soon a sexually teased correspondence ensues. He has written 12 books--as has John Nichols--including a recent novel about violence in America. He also lives in Taos, N. M., loves to fly-fish for trout, hunt for grouse, watch the seasons play across his small irrigated acreage. And he senses that he is dying. At any moment, and most likely in some moment that will come soon, his heart will fail and stop beating. The woman arrives in Taos. For several weeks they have an affair, then she leaves and he remains.

From these slight materials, Nichols has constructed a novella, and in a career studded with wonders, it is one of the finest things he has ever written.

“The Milagro Beanfield War” had a rambunctious energy; now Nichols must face up to the faltering steps that lead to death. But the tone here is not of a lion in winter but more the sound and thoughts of a booming boy who has finally slowed down a bit.

The uncomfortable junction in American life he charted in “American Blood,” the place where men and women and sex and violence meet as if on a dark and frightening street corner, is here further explored with the 19-year-old as guide. The writer is constantly prodded by her to live his appetites instead of shutting them off with kowtows to common decency, standards and civility. In fact, the 50-year-old writer wonders if his entire life and career have been a long artful act of choking.

“When he tarried at a clump of delicate white mushrooms half submerged in tall green grass, she asked, ‘Are they poisonous?’

“ ‘I don’t know.’

“She nudged her toe forward and casually rent them asunder.

“ ‘They don’t look poisonous.’

“He envied her casual annihilations. He would have enjoyed some freedom from the weight of his conscience. It might have been exhilarating to participate in the voluptuous trashing of life.”

“An Elegy for September” is sustained by sex and desire. It is about a man seeking some kind of wisdom, but Nichols is too wise to deliver any maxims or a laundry list of do’s and don’ts. The story rests on absolutely concrete acts and things: She leads him into a pornographic book store; he is embarrassed. They enter a booth and watch an arcade film of two men fornicating with a woman; then they strip as they watch and have at each other.

The sentences are brief and rooted in physical description, and the slender volume has the feel of some kind of metaphysical text that is constructed from bricks and mortar instead of vagaries. The New Mexico rendered in Nichols’ word-and-picture books of the ‘80s, “A Fragile Beauty” and “On the Mesa,” for example, here becomes the ground for forbidden thoughts. There are no boundaries any more, certainly not the constraints of left-liberal politics.

The career of the writer in the novel is in serious question. The woman tells him, “You’re a coward, a wuss. I despise you. Everything you do is play-acting. Nothing is real, you only have courage in your books. You pretend to be bad but you’re just a little boy in short pants. Your passion isn’t real, it’s make-believe. You’re hopelessly old-fashioned. You always play it safe. You ditch women before the going gets tough. You’re afraid to be evil. You’re like a devil in Triple-A ball, you’ll never make the majors.”

And the writer, staring back at a lifetime of work, is not so comfortable with his efforts either. He says, “I have instincts, but I’m not very articulate about them. I just leap right in and bull ahead willy-nilly. . . . I always begin with such grandiose hopes; I always wind up just trying to salvage a novel.”

Clearly, this fictional work bears resemblance to John Nichols’ actual life; readers who know his work will find many references to his earlier books and a kind of critical commentary on them. But the similarities between his life and this fiction are hardly what is significant. In fact, the stuff of the story, the plot, is not very important. “An Elegy for September” is a short book you can read in one sitting, and then when you finish you begin reading it again. “The Milagro Beanfield War” continues, “The Nirvana Blues” play on, “American Blood” continues to spill, but this time on darker and yet more achingly loving ground.

Maybe this book is a masterpiece. I’ll let time and wiser heads decide that matter. I just know it is alive and seductive and threatening and true. It works, lives on the page, and plunges ahead recklessly with the reader a willing hostage to the tale. The writing is stripped, simple and beautiful. The feel of things is palpable. And that is all that matters.