They call her The Madame.

Many people around here can't pronounce her name, but they know she is somebody. Internationally famous. One of the greatest living writers, they are told. When she comes into town she makes shy conversation with them. If she doesn't, they politely pretend she isn't there. And when strangers ask about her, they shake their heads and look vague and say, "Who?"

It's the custom in Northeast Harbor, maybe even more than in other Maine villages. Look in the phone book and you find Rockefellers and Saltonstalls and a lot of other famous names, and the instinct in Maine is to protect such people, and all people who want to be private, from invaders.

Marguerite Yourcenar is unlisted. Strangers come to town, and when they don't find her in the phone book they ask where she lives.

"Who?"

Even so, cars cruise slowly past her house almost every day in the summer, and tourists jump out to take pictures of the place, a modest white cottage, "Petite Plaisance." This is one of those towns where the houses have names.

Last year a young European woman arrived at the house at 9 in the morning with two suitcases and wanted to be taken in. She was told to go away. But she sat on her suitcases by the road all day. That night she finally left, but next morning she was back. The police had to be called.

Mme. Yourcenar says she doesn't mind when people take photos of the house, "if they are civil," but it is irritating to feel that she can't sit in her yard without having her picture snapped by some passer-by. Once when she went bird watching two people popped up, introduced themselves to her and said they had followed her for an hour.

But the question most people seem to ask is not why Marguerite Yourcenar, 80, best known for her novel "Memoirs of Hadrian," and the only woman to be elected to the French Academy in its 348 years, attracts this sort of celebrity, but rather, What is she doing hiding out in Maine? For some reason it puzzles people. A Frenchwoman of profound culture, student of language and the classics, stylist and philosopher . . . in Maine?

The answer is fairly simple. She likes it. She discovered it in 1942, two years after emigrating to America, and in 1951 she and her longtime friend and translator Grace Frick bought this house. For a time in the early '70s, when Grace Frick was ill with Hodgkin's disease and couldn't be moved, the two women lived there year-round, but otherwise the place has been mainly a summer home for the novelist.

"The winters here are very fine until the end of January," she says. "February, March and even April are a drag. One gets cabin fever. But it is very pleasant living here. When I came here for the first time in the last year of the World War, there were fewer houses and people. It was beautiful then. The people were working people. Now it is more chic, especially in summer."

Winters, she travels: to France nearly every year, or her native Belgium; to Japan for three months last year; to India; to Bangkok last January; to the Yucata'n. But for the summers, it is Northeast Harbor, with its birds and wildflowers, its rocky coast and the smell of the sea.

In any case, she is hardly isolated. Maine is not New York City, but it is not the edge of the world, either. Yourcenar is a familiar figure at Sherman's bookstore here, and several of her novels are regularly stocked.

"We do a lot of ordering for her," the clerk says. "She's a good customer. The locals buy her books because they're interested in her."

Town librarian Bob Pyle sees her too, "though not as much since she became immortal. She constantly sends us books but doesn't come in herself much. Grace Frick used to be her advance guard, and we'd see more of her, before she died."

He is being only partly ironic with "immortal," for that is the title given to the 40 members of the French Academy, to which Yourcenar was elected in 1981. Imagine the uproar: The Academy had turned down the likes of double Nobel winner Marie Curie, George Sand, Colette, Simone de Beauvoir and Mme. de Stael (not to mention Proust, Balzac, Flaubert and Dumas), yet suddenly it was interested in a woman who, though she still wrote in French, had lived in America for 41 years and was a naturalized American citizen.

Furthermore, she didn't even bother campaigning for the election, as is customary, but went bird watching in the Caribbean. And when elected she refused to wear the official green frock suit embroidered in gold or to carry a sword. She was instead given an ancient Roman gold medallion to wear.

Obviously, Marguerite Yourcenar is very big in France. She had a best seller with "Hadrian" in 1951, and her supporters have called her one of the greatest writers of the century. But America is still discovering her. Only four of her eight novels have been published here. There are also poems, of which only "Fires" has come out in English (1981), essays, two volumes of her autobiography, in which she barely appears (the first volume ends with her mother's death when Marguerite was eight days old; the third and final volume will end in her 25th year, when her father died), and many translations ranging from the five Noh plays of the Japanese novelist Yukio Mishima to Henry James and Virginia Woolf to James Baldwin.

"I am also publishing an album of blues and gospel songs in America," she says. "And I am beginning to write a book which probably will take me a few months: 'Le Tour de la Prison,' the story of a tour around the world. The publishers want to translate it as 'Looking at This, Our Prison.' " She winces. "It needs to be in French. But we are not to the point of arguing about the title yet. I reached page 50 today."

She works every day, sometimes typing, sometimes sitting in the garden writing in longhand (which she must copy right away because her handwriting is so bad). She used to take a portable typewriter when she traveled, but she broke three in three years, so she uses notebooks now.

"I do not sit at a typewriter at 9 and write until 11. I could never write three pages a day regularly. It would be nothing at all or maybe 10 pages."

Her speech comes out like formal prose. Contractions are rare. Precision of language means a great deal to her.

"It is very hard seeing your own work translated," she says. "The two languages where I can really efficiently help are Italian and English, and then of course I take a lot of care."

Putting James Baldwin into French was hard because "when you have the direct expression and the really vital language of rather simple people, French doesn't do it as well as English."

It so happens that the traditional function of the Academy is to control the French language by producing a new official dictionary every 50 years. This helps to police the language, so that it has far fewer words than English and little of the raffish fringe of short-lived slang that keeps American English particularly in such a creative froth.

Usually French is spoken in "Petite Plaisance." At the moment there is "a charming young friend from New Hampshire who is coming to be an intermittent inmate of this house," and the translator Dori Katz, and the writer's traveling companion, photographer Jerry Wilson.

Yourcenar's fascination with the subtleties of language--and the subtleties of thought that lie behind them--may have something to do with her habit of coming back to a book over the years, sometimes rewriting it completely.

"Some think I do it for every one of my novels. This was not true for 'Alexis' or 'Coup de Grace' but it is true for 'Denier du Reve' in English, "A Coin in Nine Hands," written in 1934 and revised in 1959, translated in 1982 . As for 'Hadrian,' it was conceived when I was very young, and I let it wait. That was more or less true for 'The Abyss': I wrote a small part, and of course it wasn't very good, and I came back one day to it."

Some books, she has said, should not be written before the age of 40.

"Memoirs of Hadrian," a stately yet magnetically readable meditation on life by the Roman emperor, takes the form of a long letter to the young Marcus Aurelius, his grandson and successor. It becomes the portrait of a great man. In her notes on the book's composition, Yourcenar says she began it in 1924, when she was 20. She destroyed the pages, wrote another 15 or so in 1934 and tore those up, too, then periodically revived and abandoned the project.

Meanwhile, her philosophy studies and her teaching of comparative literature at Sarah Lawrence kept her close to the subject. She fell in love with some Piranesi engravings of Hadrian's villa and a Canaletto painting of Rome in the Hartford, Conn., museum. Finally, in December 1948, she was sitting before the fire burning old letters and papers she had left in Switzerland before the war. She tells it in the comments on "Hadrian":

"As I unfolded and threw mechanically into the fire that exchange of dead thoughts between a Marie and a Franc,ois or a Paul, long since disappeared, I came upon four or five typewritten sheets, the paper of which had turned yellow. The salutation told me nothing: 'My dear Mark . . .' Mark . . . what friend or love, what distant relative was this? I could not recall the name at all. It was several minutes before I remembered that Mark stood here for Marcus Aurelius, and that I had in hand a fragment of the lost manuscript. From that moment there was no question but that this book must be taken up again, whatever the cost."

It is hard to find a reader who refuses to love "Hadrian." The man comes through so clearly, in the loneliness of his intelligence, in his practiced but wary handling of his own immense power, in his grief over the death of his young lover Antinous, that we feel this is what greatness must be like.

"There is but one thing in which I feel superior to most men," Hadrian writes: "I am freer, and at the same time more compliant, than they dare to be. Nearly all of them fail to recognize their due liberty, and likewise their true servitude. They curse their fetters, but seem sometimes to find them matter for pride. Yet they pass their days in vain license, and do not know how to fashion for themselves the lightest yoke. For my part I have sought liberty more than power, and power only because it can lead to freedom."

A spare, self-examined man living in a world of riotous indulgence, he had the secret pleasures of a solitary:

"Overeating is a Roman vice, but moderation has always been my delight. . . . My poor Lucius used to amuse himself by concocting delicacies for me; his pheasant pasties with their skillful blending of ham and spice bore witness to an art which is as exacting as that of a musician or painter, but I could not help regretting the unadulterated flesh of the fine bird. Greece knew better about such things: her resin-steeped wine, her bread sprinkled with sesame seed, fish grilled at the very edge of the sea and unevenly blackened by the fire, or seasoned here and there by the grit of sand. . . ."

"The Abyss," written in '68 and translated eight years later, is another attempt to get inside the mind and life of someone living in the distant past so as to recreate a lost world. Here, the hero is a fictional 16th-century alchemist and doctor named Zeno. He has a bit of Leonardo in him, also Roger Bacon, Erasmus and a handful of rational thinkers hounded for their unblinking empirical examination of the world around them.

The book is a brilliant tapestry of western Europe in the Middle Ages, as sharply detailed as a Breughel, so rich in smells and sounds and scenes that it seems like superb reporting. Zeno's dispassionate observation of his own death, after he opens his veins to cheat the Inquisition torturers, has a terrible beauty: austere and tender, it brings this brave, calm man vibrantly to life even as he is dying. It absolutely dwarfs nearly all other fictional deaths.

"The whole book is practically in a page and a half of a short story I wrote when I was 22. It is very curious; I cannot quite understand that phenomenon. Some books you have to write before 40, but after that the great point is to take your time and think. You realize life is a chaos . . ."

Perhaps it is the comprehension of life as chaos that makes an older writer reluctant to define it; hence the rewritings.

Though she admires Hadrian as one of the few great emperors of history and feels a kinship with him, "Zeno is closer to me because he lives in a troubled time like our own, a more tragic time, when the act of self-examination is dangerous." A new novella, "Un Homme Obscure," not yet translated, is about another man like Hadrian and Zeno, "so terribly intelligent that he's never taken in but sees all things in perfect clarity," yet is barely educated and fated to live in obscurity. She may rework this into a larger novel for a trilogy.

"Yourcenar" is an anagram of sorts for de Crayencour, her family name. Born in Brussels in 1903, she never went to school but was tutored by her father, read Racine at 8, Latin at 10, Greek at 12. Her father, wealthy and of old family, died when she was 24, whereupon she began to write seriously, publishing her first novel, "Alexis," in 1929. Ten years later, an established writer, she fled Paris to visit her American friend Grace Frick. The visit turned out to be permanent: As the war stretched on, she used up her money and had to get a job as teacher. Then "Hadrian's" success changed everything.

Marguerite Yourcenar is a disciplined person whose shyness may be a defense against the chaos of life, but she never lets it prevent her from observing her fellow passengers wherever they may be on the planet.

"Going to a new country is really an experience that is never to be forgotten," she says. "You never quite know what you will find. You can continually learn from people. Each meeting with a person is a very strange, shall I say, chemical experience. Nothing can come of it, we can phase out very rapidly . . . But it can be something that can change you forever."

Even, she might add, in Maine.