MARGARET JAMES, 37, lay in bed dreading the new day. It was raining again, the bedding felt cold and damp, and even her hair seemed permeated by that dusty, musty odor she had come to associate with everything Australian.

It had been three years since Margaret and Tom James, in pursuit of a better life, emigrated with their four children from Detroit to Sydney.

As she stood in her unheated bathroom, bracing herself to step into the tepid trickle of the ancient, groaning shower, she struggled to remember whatever had possessed them to leave the United States of America in the first place.

At the time, she recalled, shivering as she dressed, it had seemed like a thrilling adventure, pioneering in a brand-new land of unspoiled beauty, endless opportunity and cute little Koala bears.

She and her husband, married at 17, had been bored with their dreary life in Detroit, where he was a quality-control inspector for Ford and she was an A & P supermarket checker. Their only goal in life, it had seemed to her in those days, was to buy a tract house in the suburbs.

Her goal in life now was to get back to the land of central heating, hot running water and decent wages as soon as possible.

She no longer took anything material for granted, not even a new pair of shoes. Margaret James, a middle-income American, had learned the meaning of being poor.

She headed downstairs where her children were already eating breakfast around the old kerosene stove. In the gray morning gloom -- it always struck her as a dramatic, Dickensian scene -- a shabby little band of paupers huddled together, their expressions sullen and old, demanding to know when this misery would end.

Margaret James hoped they would be rescued any day now, because Tom James had returned to America to work six months ago. Barely able to make ends meet in Australia, the Jameses had finally decided there was no other way they would ever be able to save the entire family's air fare home.

Meanwhile, however, with her husband gone, Margaret James, who earned $51 weekly at a Sydney supermarket, had not been able to keep her family fed. And so, her two oldest children, 15 and 16, had been forced to quit school and go to work, too. The boy sold department store appliances and the girl worked all day in a sandwich shop.

And, of all her hardships as an American emigrant abroad, it was this one alone that sometimes made Margaret James cry at night.

It happens all the time. Americans are constantly packing their bags and kissing off their homeland, in hopes that life will be better elsewhere.

Just how often it happens, however, is anybody's guess. Since few of even the most cynical expatriates are willing to forfeit their U.S. citizenship, the State Department has no way of determining which of the thousands of Americans living abroad at any given time are long-term tourists and how many regard themselves as full-fledged emigrants.

In fact, according to State Department statistician Eula Landemore, no official effort to keep track of American emigrants has been made since 1957, when the Immigration and Naturalization Service concluded that its own program was a confusing, inaccurate failure. "At best, it was never much more than educated guesswork," she says.

Nonetheless, authorities continue to venture educated guesses about American emigration patterns. Among other things, most agree that despite the publicity generated by the exodus of young draft evaders during the Vietnam war, neither age nor politics has any special bearing on emigration.

To the contrary, Americans of all ages and backgrounds scatter regularly to countries all over the globe. "I think it's practically becoming a national pastime to abandon the nation," says one cynical American now living in London. "After all, it's always been a fashionable thing to do."

Fashionable or not, it is clear that good old-fashioned patriotism not withstanding, emigration is no big deal to many Americans nowadays. Many simply pick up and go -- sometimes for economic reasons, other times for sheer adventure, occasionally out of disgust at America, and, oftentimes, for personal reasons ranging from loneliness, frustration, and anger to simple boredom.

And, many discover, sooner or later, that the grass is no greener across the border. Most, it seems, come home, like Margaret and Tom James, because they have been economically whipped. Either they couldn't find jobs or, if they did, they discovered that they were being paid too little to survive in a high-priced country.

And it is a rare American who moves to Rome, literally intending to do as the. Romans do. Americans abroad expect to live as well as, if not considerably better than, they did at home. Hardship is a matter of novelty, to be suffered strictly at one's individual discretion -- and when the novelty wears off, American patience quickly runs out.

Other Americans return home because, quite simply, they get lonely. Even if they understand the language, the cultural, religious, historical and political differences often combine to underscore to the American that he is, and will always be, "a foreigner." Someone who can never really belong.

Often, too, this feeling of alienation exists whether the American has settled into a country friendly or hostile to the U.S. government. Either way, he is likely to be saddled with a stereotype, whether it is that all Americans are rich or that they are all warmongering imperialist dogs.

Americans obviously come home for countless other reasons, too -- everything from their sudden craving for a Big Mac every Saturday night to their concern about property rights abroad.

All these motives, plus a few others, were described in detail by these repatriated Americans:

A handsome, swashbucking entrepreneur, 42 -- given to black suede Stetsons, the music of Willie Nelson, French cuisine and the works of Joseph Conrad -- who emigrated to El Salvador because he wanted "to live like a king."

An aging Jewish couple who emigrated to Israel, not for the love of Zion but strictly because he was an unemployed aerospace engineer who needed a job.

A Los Angeles-born Chicano, 25, who went to Mexico because he felt like a second-class citizen in America.

A comfortably affluent Philadelphian, 30, who, finding American women "gaudy," emigrated to the Continent on an old-fashioned wife hunt.

A sophisticated, successful Los Angeles import-export executive, 50, enchanted with opulence, who moved to Morocco to hobnob with sultans and sheiks, princes and kings.

A closet homosexual, then 29, who went to Australia to escape from his father, an Ohio cheese salesman, while he sought his sexual identity.

A congenial, laid-back, self-described loafer, 32, who, several times married, went to Brazil to escape attorneys harassing him for back child support and alimony payments.

And, a college dropout, who went to Denmark, at 18, in pursuit of free sex and an infinite supply of low-cost hashish, incidentally learning on the way to abhor war and American politicians, too.

An unlikely collection of Americans, to be sure. But they have more in common than their mutual status as former emigrants. Among other things, none complains anymore about taxes, inflation, traffic jams, billboards or crowded golf courses. They appreciate chainburgers, laundromats, campaign rhetoric, telephones and even the most mindless TV sitcom.

One of them even sports an old car bumper sticker, salvaged from the '60s, saying "Love It or Leave It."

Having left it, they now all love it -- with a shameless passion you might find refreshing in these tepid times.

"It was terrible. I was cold more often than I ever was in Detroit, I can still remember that awful musty smell to everything, and we all worked harder than we ever had in our lives -- and got nothing but the barest survival in return," says Margaret James, now 42, speaking of her family's Australian experience, which still sends a shudder up her spine.

"But I still wouldn't trade the experience for anything, because, if we didn't get our fresh new start in Australia, it helped us to get one when we came home. We learned a lot about ourselves in Australia, and we learned to appreciate America as we hadn't done before. I never felt so free."

The first thing Margaret and Tom James did upon their return was move to California and get a divorce, having decided that Detroit was merely a scapegoat for their own bad marriage. Then, they enrolled all their children in school again.

After that, they set about appreciating the smaller things in life: "like the choices Americans have, in supermarkets, furniture stores, dress shops -- you don't find that luxury in Australia."

Now a data processor, Margaret James discovered that Australia is one of the most sexist societies in the civilized world, a place "where women still can't go into bars alone or get credit without a male co-signature."

Ironically, she recalls good-naturedly, Australians make no allowances for female physical frailties, so she now knows, firsthand, that they do exist.

"It was a nightmare," the slender, fragile-boned woman says with a laugh. "Not only did I end up working in a supermarket, just like in Detroit, but, in that country, they expect the women checkers to stock the shelves too! That's back-breaking work, I discovered. I had aching muscles for three years."

Margaret James does not want to sound totally negative, however. Public transportation was cheap and excellent. "Which was a good thing, since a car costs around $10,000."

Australian public schools put American education to shame, she and her children all agree. Junior high school students learn college trigonometry. When the James children reentered American schools, they were skipped grades ahead.

But most tourist literature is misleading, Mrs. James says. "It's sort of like advertising America with nothing but pictures of Yosemite. Australia has big, smoggy industrial cities, too. And the only Koala bear I saw was in a zoo.

"I hate to sound like a bad sport," she concludes, "but, the truth is, Americans are spoiled. For all the other emigrants in Australia -- the Southern Europeans, people from Ceylon Chile -- living conditions were a definite step up. But they don't take cars, telephones and refrigerators for granted like we do....

"So, my advice to any would-be emigrant is this: Don't ever leave America without having your return fare safely stashed away somewhere. And, when people tell you that the standard of living is lower in another country, listen to them. There's nothing romantic about not being able to afford a refrigerator or a new coat."

Edith Ostrow, now 61, couldn't agree with Margaret James more. Mrs. Ostrow, a frail, nervous little woman with chronic health problems, never wanted to emigrate to Israel in the first place, but her husband Joseph, 67, talked her into it.

Just another aging, unemployed aerospace engineer in America, he knew he would be welcomed with open arms in Tel Aviv.

Joseph Ostrow also spoke to his wife of their Jewish heritage, of the twilight years, of their need to settle down.

She listened.

They emigrated in 1970. Sixteen months later, Edith Ostrow had firmly concluded that having roots isn't everything.

"First, in Israel, you have to wait for months just to get an apartment, the housing shortage is so severe," she says. "Then, when you finally get one -- and we were assigned by the government to one of the loveliest areas -- you discover that all you get are the bare walls. Literally. There are no kitchen applicances, no light fixtures, no closets, not even the toilet bowl. You have to buy those things on your own. It's the European plan, they told me."

No big deal for affluent emigrants, perhaps. But Joseph Ostrow, an aviation flight inspector, earned only $300 a month. The apartment rent was $60. Their teen-age daughter was with them. Simple appliances cost three times their American price. Edith Ostrow found herself hanging clothes from laundry wire strung across the living room and doing all her laundry, except the sheets, by hand in a huge tub. It was back-breaking work.

But, like Margaret James, she hates to sound like a spoiled American.

"To tell the truth, it was very hard for me," she says tentatively, almost apologetically. "Joseph had his work. But I spoke no Hebrew. I was in my late 50s and I was partially blind in one eye. I was very lonely. I couldn't understand even the simplest things, like how to shop for good prices at the small markets, instead of the supermarkets....

"But, mostly, it was the laundry. It became a symbol. After a few months, I believed that happiness in this world amounts to one thing only -- owning an automatic washer."

Obviously, Joseph Ostrow, who liked his job, would have been pleased to buy his wife a washing machine. But, by the time he had saved the money, it was too late. By then, Edith Ostrow was blaming her discontent on all things Israeli.

She was afraid of terrorist attacks, she said. She felt guilty going shopping on Saturdays, when pious Jews did not even light their stoves. She came to hate the odor of Gefilte fish, the sight of Yarmulkes and the sounds of Hebrew conversations. Edith Ostrow, daughter of a long line of New York Jews, was becoming in effect, anti-Semitic.

The Ostrows now live in Hollywood, in the old Knickerbocker Hotel, recently converted into a low-cost hostelry for senior citizens who live primarily on Social Security.

He is unhappy. "In Israel, I could have worked, most likely, until I was 75," he says, watching a TV game show. "Here, I am a useless old man."

"There's a lot to be said for being a big fish in a little pond," drawls Royce Davis, who invested his money in a construction business in El Salvador, went broke two years later and is now back home, hustling the real estate market in order to recoup his losses.

A candid man, Davis says he picked El Salvador because, apart from his natural affinity for Central American political intrigue, "I knew I could live like a king there -- and I did."

He lived in a sprawling home, drove one of the two Lincoln Continentals in town, and had servants. Women fell all over him, and he had a wonderful feeling of power.

"I mean, just the fact that I'm 6 feet 4 and the average guy down there is 5-5 made me feel terrific," he says, grinning. "And, if they'd admit it, most Americans emigrate with this fantasy of living like a Yankee God. We're spoiled in this country, you see. We constantly dream of getting more than what we've got. And we usually do.

"But, in a small developing country like El Salvador, you can take your Yankee dollars down and actually own people who have nothing. Americans love being looked up to."

And so, when Davis lost his money -- "through simple, stupid mismanagement" -- he never dreamed of staying in El Salvador.

"And get some puny little job, for maybe $300 a month, and live like they do? Ha," says Davis, who looks the part of soldier of fortune, with his dark beard, black Stetson and swaggering ease.

Besides, Davis says, when the good life and the power trip vanish, there's not a lot to recommend El Salvador over the United States. The weather's better in California. And, he's not as lonely in Los Angeles.

Married five times already, Davis has no interest in finding another wife, he says. But "I do enjoy communicating with women of my own age." In El Salvador, not only was he handicapped by speaking only passable Spanish, "but most of the women my age have been married 20 years, with 10 kids. Which leaves me with a lot of 19-year-old girls to mess around with -- and, believe it or not, that gets old." He adds, "I wanted to really get to know the Salvadoreans as people -- but, for an American in my position, that is never possible."

All things considered, Davis says, he is not at all unhappy to be back home again, although he will probably emigrate again, when he gets some money together.

"I'm part of that generation that read romantic travel books. I'm programmed to keep hunting for the frontier," he says simply. "But, one thing is certain: There's no way in Hell I'd ever even consider giving up my U.S. citizenship."