BOOK REVIEW / HISTORY : Handful of Refugees Fleeing Czar and Stalin Live on Faith : LOST IN THE TAIGA One Russian Family’s Fifty-Year Struggle for Survival and Religious Freedom in the Siberian Wilderness, <i> by Vasily Peskov</i> , translated by Marian Schwartz. Doubleday; $26.95, 254 pages

“Lost in the Taiga” is one of the most remarkable stories to emerge from the smoke and rubble of the former Soviet Union, a shining saga of survival in the Siberian wilderness that also serves as a kind of parable about the function of faith and tradition in the history and destiny of Russia.

The story begins in 1978, when a party of Soviet geologists was surveying a remote stretch of wilderness by helicopter in search of iron ore deposits. To their astonishment, they observed a rough-hewn cabin and a cultivated garden in an otherwise pristine and wholly inaccessible portion of the vast coniferous forest known as the “taiga.”

What the geologists had discovered--and what Soviet journalist Vasily Peskov went on to investigate in intimate detail--was the refuge of a family of “Old Believers” who fled from the worst excesses of Stalinism in the 1930s and who managed to preserve themselves for nearly a half-century on the strength of their survival skills and their abundant faith.

“Their existence, squalid in the extreme,” observes Peskov, “consisted of prayers, reading prayer books, and a genuine struggle for existence in nearly primeval conditions.”

When a party of curious but cautious geologists, bearing both gifts and arms, finally reached the mysterious encampment, they found a scene “like something halfway between Peter the Great and the Stone Age.” The Lykov family dressed in rough burlap, they lived on pine nuts and potatoes, they drank out of birch-bark vessels--and suddenly they were face to face with the 20th Century.

“Greetings, grandfather!” one geologist hailed the long-bearded patriarch of the family, Karp Lykov. “We’ve come to visit.”

“This is for our sins, our sins!” cried one of the women who huddled in fear in a dark corner of the cabin.

As it turned out, the family belonged to a sect that had broken away from the Russian Orthodox Church in the days of Peter the Great.

Indeed, the long-dead czar and his churchmen “were for Karp Osipovich implacable, intimate, and personal foes.” And it was the religious fervor of the Lykov family that sustained them over the long years of self-imposed exile.

“Often conversation was broken off by their impulse to go pray that very second,” recalls Peskov. “The prayer stopped as abruptly as it had begun, and the conversation took up where it left off.”

Peskov visited (and wrote about) the Lykovs over more than a decade, and he watched as the family slowly acquainted itself with the history and technology of the world they had shunned.

They rejoiced at gifts of a piece of canvas, a kitten, a spinning wheel, but they refused a box of matches: “Sinful fire,” says Karp Lykov, who refused to give up the flint and tinder that he used to strike a flame. “Our trick is better.”

According to Peskov, the Lykovs came to welcome the intrusion of the outside world, and he refuses to depict their experience as a casting out from Eden. “We were starting to wear out,” says Agafia, Karp Lykov’s daughter. “We were eating without salt.”

But there’s a faint trace of Adam and Eve in his tale, and Peskov observes that “an avid curiosity awoke in (the family), a desire to learn and understand.”

The story of the Lykov family is so remarkable, so moving and so well-told that I wondered at first if they were not a kind of Siberian version of the Tasaday tribe of the Philippine rain forest: Was “Lost in the Taiga” a good yarn made even better by some colorful embellishments?

Still, we have no reason to believe that Peskov is not telling us exactly what he saw.

Today, the last survivor of the Lykov family is Agafia, a 50-year-old woman who lives utterly alone in the taiga and refuses to seek the company of other human beings.

“I shall live as we have always lived,” vows Agafia, and her words resonate with larger meanings as we contemplate not only her own curious fate but the destiny of Russia itself.