When I was a boy, my mother's father lived with us. We called him Poppy. He'd been a drummer in the Czar's army but escaped and came to America, where he worked as a house painter, though by the time I knew him he was retired. It used to drive my mother crazy the way he sat in her kitchen drumming his fingers on the table.

Another story: Long before, when my mother was only 5 years old, her favorite cousin Charley (who was Poppy's brother's son), came to say goodbye. An immigrant himself, he was wearing the uniform of the U.S. army, going off to serve in World War I. Even now it brings tears to my mother's eyes to recall that Charley was killed in action on the day before the Armistice. I never knew him, of course, but the family used the money from his government life-insurance policy to bring over his brothers and sisters from the old country - Peshie, Goldie, Irma, Al and Mac, middle-aged and old themselves when I first knew them in the 1950s.

All of these people entered America through Ellis Island, as did everyone on my father's side, too - parents, uncles, cousins, all Yiddish-speaking immigrants from Russia, the Ukraine, Lithuania and the Pale of Settlement. So Ellis Island, three acres just past the Narrows in New York Harbor, has assumed for me a kind of mythic status in my family's beginnings in this country. The first American soil on which they set their feet, it has the status of a kind of Jewish holy place.

I don't think I am unique in this regard.

But visiting the museum into which Ellis Island has now been converted, I was surprised to bump up against the (obvious, of course) fact that it was not only Jews, not even mainly Jews, who came through that open portal. Four million Italians, 2.3 million Jews and more than 6 million Irish, Russians, Poles, Finns, Greeks, Turks, Gypsies, Slovaks and Czechs, Croats and Serbs, Armenians, Arabs, blacks from the Caribbean, even Japanese came off the boats and into the echoing, huge "Registry Room."

This most extensive controlled immigration in history began in 1892, when the first Ellis Island immigrant, a 15-year-old Irish girl, was given a $10 gold piece to celebrate her arrival. It lasted until 1954, when the center was finally closed. From its beginning, almost immediately, it changed the face of America forever. By 1910, 75 percent of the residents of New York, Chicago, Cleveland and Boston were immigrants or the children of immigrants. Of the current U.S. population, 42 percent, or one hundred million people, have ancestors who came through Ellis Island.

The irony, given how large Ellis looms in the immigrant legend, is that most of the immigrants spent only a few hours there being "processed" before they boarded trains to other cities or relatives took them home.

The ones who stayed on the island overnight were mainly the sick, the incompetent, those who could not convince any inspector that they would not become wards of the state. These people were fed and dormitoried while their examinations continued, until their appeals were complete. (Many immigrants got their first taste of bananas, ice cream and white bread at Ellis Island. In 1911, a kosher kitchen was established at the processing center, specifically because so many Jews arrived undernourished after a trip on which they refused to eat the treif ship food.)

Immigration was fueled by economic hardship and ethnic persecution in Europe, but what made it possible was 19th-century advances in the technology of transportation - trains to bring migrants to the port cities and steamships that could carry them across the ocean in large numbers, cheaply and relatively quickly.

The typical steamship journey was 15 to 21 days. When the ship, which carried first-class and second-class as well as steerage passengers, arrived in the Narrows, the entrance to New York Harbor, it would be "quarantined," detained for medical examinations. Then the ship docked to disembark the first- and second-class passengers. Steerage-class passengers were taken to Ellis Island, hauling their baggage with them into the huge "baggage room" of the processing center, a building that - restored at a cost of $156 million and opened to the public in September, 1990, as the Ellis Island Museum - looks like an extravagant old Georgian mansion. (If they were smart, the immigrants kept their baggage with them all the time instead of leaving it in the baggage room. Especially in the early years of the immigration, valuables were commonly stolen by corrupt workers.)

Today, side rooms on each of the museum's three floors contain exhibits of artifacts, models, photos and documents explaining the history of the immigration and the work of the processing center. But the balconied "Registry Room" - which is the true heart of the museum - is empty. A huge high echoing empty room.

In its very emptiness lies its power to move the visitor. The imagination fills in the crowds of immigrants as they move slowly up the double staircase into the huge room. As you come, you are watched by doctors at the top of the stairs. If you seem out of breath, if your gait is uneven, if you seem ill or confused, a chalk mark is put on your coat - H for heart; L for lame; F for facial rash; Sc for scalp infection; X for mental - and you will be examined further. (For a Jew, this sort of benign selection resonates uncomfortably, perhaps, with that other "selection" that sent the old, ill, all the "useless" to death by gas chambers - but this was the door to freedom.)

Then immigrants were routed elsewhere for other examinations, for further processing, into rooms now used for museum exhibitions. Tuberculosis or an eye disease called trachoma was a cause for deportation. So was destitution: Immigrants were sent back if they had less than $25 - although they might get through without the money if they were skilled and would be able to fend for themselves. (Often the same $25 was palmed from one immigrant to the next in line, planting many penniless individuals in the new country.)

The entire process took four to six hours for each person. First twenty stinking, rolling days at sea, then the sight of the Statue of Liberty, its torch aloft in the harbor - "A city in heaven," one immigrant called it - then four hours at Ellis Island; and from there they fanned out, with the help of relatives and immigrant-aid societies into the land of opportunity. The streets were not paved with gold, but it wasn't, in general, a bad metaphor.

Four to six hours made Ellis Island an icon of American immigrant experience. It was only those being held for further examination or appealing deportation orders who stayed longer. Then, if they were rejected, they would be shipped, steerage class and "tempest toss'd," at the shipping line's expense, back to Europe. Ultimately, 2 percent of the immigrants, a quarter of a million souls, were sent back, frequently requiring painful separations of family members.

Now, though the Registry Room is empty, the mind somehow still hears the hubbub, the cries, groans, shouts, laughter, as if the mechanism of immigration is still operating, as if all that human hope, need, sorrow still remains. My mother says that when she visited the building in the early 1980s, before it was restored, she burst spontaneously into tears, she cannot say why.

After restrictive immigration laws reduced the flood of immigrants in the 1920s and 30s, Ellis Island became a detention center for small numbers of suspicious aliens and, later, for displaced persons. The facility decayed and, after it was closed in 1954, became increasingly dilapidated. The museum has changed that, of course. Over the years landfill has expanded the Island's three acres to 27, most of them still off limits to visitors.

Next to the museum is a little park where visitors - more than 2 million people visited Ellis Island during its first year - can enjoy the salt air and the view. At the edge of the island - in one direction, one faces the pointed tip of Manhattan Island and the New York skyline; in another, one sees the Narrows and the opening to the Atlantic -- is a waist-high, very long metal "seawall." On it are inscribed, for purposes of both commemoration and fund-raising (the museum charges $100 for each name), the names of thousands of immigrants - row after row of them, a litany of the American melting pot.

We are, I think, closer to the immigrant experience than most of us realize. We who are native born, who speak the native language so well, who are Americans, may often fail to see how the immigration has shaped us.

My mother and I are going over family history, retelling the fragmentary stories that are our family's private treasure. One of my favorites - again, perhaps because it is so typical - is of my mother's aunt, Poppy's brother Abe's wife Rose. Abe died before his time - "a young man," my mother says - and left Rose a widow with five small children. She washed floors in office buildings and plucked chickens in a kosher slaughtering house to support her children and managed to put them through college (God bless the public university system). All five of them, sons and daughters, earned college degrees and became teachers and administrators in the New York City school system.

Such are the heroic stories of our near ancestors.

As we talk, I idly ask where the members of our immediate family slept in those years, the late 1940s and early 1950s, when we lived - my parents, Poppy, my brother and me - in a two-bedroom apartment on Ocean Parkway in Brooklyn. My mother thinks about it: She and my father in one bedroom, my brother and I in the other, Poppy in the living room - but that was only after I was born. At first, Poppy had the other bedroom, my brother was in the living room, his place made up anew each evening. In these details I catch a glimpse of crowdedness accepted without question, a kind of family heat.

And then I consider other, less tangible things - my parents' over-protectiveness to me, the insistence on frugality, the concern with "eating well," the strong patriotism seasoned by the lingering sense of threat from goyish America, their absolute respect for the learned and for those in authority, their love for American popular culture mixed oddly with contempt for its ultimate foolishness, their insistence on Jewish identity even as they sent me to public schools and turned my ambitions toward the larger culture.

Many miles, years, experiences later, I too remain formed by the immigrant experience, by the ambiguities of acculturation.

And yet, we are not immigrants, and it is not 1918 or even 1958. Poppy, who wore long underwear with a "flap" and taught me pinochle, that Jewish card game, is dead more than 30 years. At the Ellis Island Museum, they have now computerized the records, creating a data bank that includes not only the names of the millions of immigrants but when they came, from where, with whom, with what skills, who was here for them, where they went.

When I return to Brooklyn from the museum, my mother and I discuss going out to eat. We consider a posh kosher eatery on Manhattan's upper West Side that has venison on its menu at something like $50 a plate, but we settle for something closer and simpler. It is something that seems to us almost ordinary, though it, too, is really quite extraordinary: a kosher Chinese place in Flatbush. Even more amazing, there are several to choose from.

To stand at Ellis Island is to face in two directions at once. And either way you face, you've come a long way, baby.