Polar Adventure : THE BIRTHDAY BOYS, <i> By Beryl Bainbridge (Carroll & Graf: $18.95; 192 pp.)</i>

“The Birthday Boys,” a new novel by the English author Beryl Bainbridge, is an imagined account of Capt. Robert Falcon Scott’s expedition to the South Pole in 1912, told in the voices of Scott and four men who followed him to their deaths. In each account a birthday is celebrated, or mentioned--thus the title. It’s an ironic touch by a novelist noted for her droll humor. A darker, more tragic story couldn’t be masquerading under a more jovial veneer.

I read “The Birthday Boys” in one sitting, in a state of complete absorption, stunned by its beauty, by the depth of its accomplishment, but perhaps most of all by the audacious choice of historical subject matter which Bainbridge has appropriated and so flawlessly rendered into fiction.

The facts of Capt. Scott’s adventure are known. His second expedition (the first failed) was mounted shortly after hearing that Shackleton, in 1911, had been forced to turn back only half a dozen marches short of the South Pole. Scott’s subsequent race for the prize was thwarted by Amundsen, who set out around the same time and beat him to the pole by a matter of days--some argue because Scott had chosen to experiment with motorized vehicles and the ill-fated ponies for transport rather than relying on the sled dogs Amundsen had favored.

But these are only the facts, and what seems less explored, and the perfect provenance for a novelist, is the deeper story of who these men really were. Each had a mother or a wife, a life he left behind, and these relationships are so subtly and economically evoked they become as much a part of the story as the physical privations that are endured.

It was a brilliant decision to chose to tell this story from five different perspectives, for it allows the complexities and contradictions to emerge. For instance, Petty Officer Taff Evans, a working-class Welshman valued for his brute strength and mechanical prowess, has a dogged devotion to Scott, who treats him with deep respect in spite of their class differences; the upper-crust Capt. Oates, sensing Scott’s weakness for making mistakes and shifting the blame to others, mutters behind his back and offers quite a different portrait of their leader.

The actual march to the pole takes up the smallest portion of the story. It’s the preparations, the long journey to Antarctica by sea, the months spent acclimating, waiting for the weather to break, Scott’s mistrust of dogs, the motors that fail or are lost, that provide the bulk of the drama.

The little recollections of the lives they’ve left behind weight the story emotionally. Scott misses his wife, whose absence feels like an “amputation.” Birdie Bowers, still a virginal young man, swears his mother appears at the edge of a crevasse and weeps frozen tears before the apparition.

To the very end, the men behave with consummate kindness toward each other. They seem to increase in humanity as their chances for survival dwindle. “One just has to believe that it’s within one’s spiritual domain to conquer difficulties,” Scott says. “That is not to say that I don’t recognize there has to be a time to submit, possibly a time to die, merely that I’ve never yet been taken to the brink.”

But he is soon taken to the brink, and beyond. Weak and starving, dispirited beyond words at finding Amundsen’s tracks at the pole when they arrive, the men turn back, huddle in their tent, their frostbitten flesh red and purple, “shining with that same sort of sweet glaze one sees on rotten meat.”

For Scott, who in his ruthlessness of purpose resembled Napoleon, there was no such word as impossible, or if there was, as one character says, it was listed in a dictionary for fools. Bravery was a conscious act of discipline. “Is it true that adversity brings out the best in men?” Dr. Wilson is asked at one point. “Yes,” is the answer, “good men, that is.”

In a sense, Bainbridge has made all five characters “good men,” by simply giving them such full and rich human dimensions. “It’s to be regretted that the best of me, the part that recognizes both the horror and beauty of destiny, remains submerged,” Scott writes. But it is exactly those submerged parts that Bainbridge excavates.

Scott always claimed that he meant his journey to be as much a scientific expedition as a quest for the pole (he derided Amundsen for being interested only in glory). In one of the most moving sections of “The Birthday Boys,” Lt. Bowers, a scientist, leads a small party to retrieve some emperor penguin eggs and endures a nightmarish ordeal. Later, musing on the horrors of that experience and the affection he feels for his companions, he comments: “It may be that the purpose of the worst journey in the world had been to collect eggs which might prove a scientific theory, but we’d unraveled a far greater mystery on the way--the missing link between God and man is brotherly love.”