1933, a summer''s day in Manhattan''s Lower East Side. There are children playing outside on East Fourth Street; it is August, and they are wild, they are shouting and running through the street, trying to gather up the last of the season before the fall sets in. There is nothing unusual about any of this. Then the door swings open at 29 East Fourth Street, and an old woman emerges on to the stoop overlooking the street, waving her arms wildly and shouting to the children to be quiet. The children, as well as the adults on the street, all recognize her: Gertrude Tredwell, who''s lived in the house for over ninety years, born there only a few years after her father purchased it in 1935. She is enraged; she tells them they are being far too noisy, they must calm down. The children quiet, turning towards the high staircase that leads to Gertrude''s front door, looking up with fear at the old woman who, satisfied, returns indoors and shuts the door.  There''s nothing unusual about any of this--except that Gertrude Tredwell has been dead now for several weeks.

It is not the last time Gertrude Tredwell will be seen at the house on East Fourth Street. In the months after her death, the house falls into the hands of a distant cousin; since by then most of the old merchant houses of lower Manhattan were gone, he decides to preserve the house as a museum, first opening it in 1936. Open to the public, over the years there are dozens of sightings of odd and inexplicable things happening in the house. In the early 1980s tourists come across the house and ring the bell. A woman in period costume tells them politely that the museum is closed for the day, and could they please come back at another time. Later, when they call the house to get the hours, they are told that the museum was in fact open when they came by, and that, furthermore, none of the staff ever dresses in period costume. Gertrude has also been seen inside the house, sometimes humming, sometimes playing the piano--always appearing as a frail, petite woman in period costume. Nor is she alone.

A visitor to the house in the summer of 1995 claimed that while upstairs she had a lengthy conversation with an older gentleman in a tattered suit and a heavy wool jacket smelling of mothballs, who talked to her of what the house was like to live in. After listening to him for a few minutes, she turned her back on him for a moment, and when she looked back, he was gone. Later she identified the man she''d seen from photographs: Samuel Lenox Tredwell, Gertrude''s brother, who''d died in 1917. Ghost stories like these mean more than we are usually prepared to admit. If you want to understand a place, ignore the boastful monuments and landmarks, and go straight to the haunted houses. Look for the darkened graveyards, the derelict hotels, the emptied and decaying old hospitals. Wait past midnight, and see what appears. Tune out the patriotic speeches and sanctioned narratives, and listen instead for the bumps in the night.

You won''t need an electronic device to capture the voices of the dead; a patient ear and an open mind will do. Once you start looking, you''ll find them everywhere. "We tell ourselves stories in order to live," Joan Didion once wrote, and that is just as true of ghost stories: we tell stories of the dead as a way of making sense of the living. More than just simple urban legends and campfire tales, ghost stories reveal the contours of our anxieties, the nature of our collective fears and desires, the things we can''t talk about in any other way. The past we''re most afraid to speak of aloud in the bright light of day is the same past that tends to linger in the ghost stories we whisper in the dark. Ghost stories are as old as human civilization, appearing in the earliest written epics and throughout the ancient world. In one of his letters the Roman writer Pliny the Younger describes a house haunted by a ghost "in the form of an old man, of extremely emaciated and squalid appearance, with a long beard and disheveled hair, rattling the chains on his feet and hands." The house remained vacant until the philosopher Athenodorus rented it; his first night he waited up for the ghost, writing in his study, until the apparition appeared.

Athenodorus, according to Pliny, was not in a hurry, and when confronted by the ghost "made a sign with his hand that he should wait a little, and threw his eyes again upon his papers." Eventually the philosopher allowed the ghost to lead him outside of the house into the yard, where he vanished. The next morning, Athenodorus dug up the spot where the ghost had disappeared, and found the remains of a skeleton in chains that had been long neglected. He gave the corpse a proper burial, and the haunting ceased. Ghosts bridge the past to the present; they speak across the seemingly insurmountable barriers of death and time, connecting us to what we thought was lost. They give us hope for a life beyond death, and because of this help us to cope with loss and grief. Their presence is the promise that we don''t have to say goodbye to our loved ones right away, and--is with Athendorous''s haunting--what was left undone in one''s life might yet be finished by one''s ghost. Perhaps this is why, even without centuries-old castles or ruined abbeys, the United States is as ghost-haunted as anywhere else in the world--perhaps even more so.

You''ll find ghosts in the stately plantations of the South, in the wilds of the plains states, in the ornate hotels of California, in the wooden colonials in the Northeast. They roam the streets of rustbelt cities like Detroit and Buffalo, and they haunt the gothic cities of the South. You''ll find them in abandoned mining towns, and in the bustling metropolis of New York City.  Forty-five percent of Americans say they believe in ghosts, and almost a third say they''ve witnessed them firsthand. Though this belief lies outside the ways we normally explain the world--contradicting science and complicating religion--it''s a difficult belief to shake. That we continue believing in ghosts despite our rational mind''s skepticism suggests that in these stories lies something crucial to the way we understand the world around us. We cannot look away, because we know something important is there. * The Merchant''s House Museum in lower Manhattan has stood by itself against the din and rush of the city; it has stood for one hundred and eighty years and might stand for that many more.

Within, walls continue upright, bricks meet neatly, wood floors give gently under foot, and spirits gather.  The house was bought by Seabury Tredwell in 1835 when he retired. Owner of a large hardware firm, he had eight children altogether, the last of whom, Gertrude, was born there in 1840 when Tredwell was sixty. Gertrude never married; she had one suitor, but her father disapproved of his Catholicism. And so she lived out her life in the house on 4th Street, her siblings dying one by one until only she remained. Over time, she focused her energies on keeping the house exactly as Seabury intended it, maintaining its nineteenth century charm until she died, at the age of ninety-three, in 1933. A distant cousin acquired the house, and since by then most of the old merchant houses of lower Manhattan were gone, he decided to preserve Tredwell''s home, first opening it to the public as a museum in 1936. The ghosts, they say, came quickly thereafter.

The Merchant''s House is a prime example of a grand old American haunted house. Its exterior is stately, refined, with a touch of frayed elegance. Its front door welcomes, even as it seems to be hiding something. Inside, the floors creak without warning, without any sense of someone there. The old wood is thick with the humidity, as if the walls and floors still breathe. It stands as the oldest brownstone in New York with its furniture still intact. All around it are gleaming glass and steel towers of the modern age, bustling with life still living. It is easy to feel as though you''re stepping back in time as you walk in the steps of those long gone.

And it''s easy, in such a well-worn house, to feel that something is not quite right: an invisible presence, a trace of something that doesn''t belong. Through the years guests have reported feeling cold spots, or seeing strange, wispy streaks of light, some of which have been captured on film. Paranormal researchers have conducted EVP (Electronic Voice Phenomena) sessions in the house, turning on a tape recorder and asking questions to an empty room, playing back the tape later in hopes the ghosts will have answered back. Several EVPs from the house have recorded bits of faint, muddled noise that some claim are voices speaking from the beyond. But these events alone are easy for a skeptic to brush aside, and discount. A paranormal event without a story is tenuous, fragile. What makes it "real," at least in a sense, is the story, the tale that grounds the event. That sense of the uncanny, of something not-quite-right, of things ever-so-slightly off, cries out for an explanation, and often we turn to ghosts.

Just as an oyster turns a speck of dirt into a pearl, the ghost story doesn''t make the feeling disappear, but can transform it into something more stable, less unsettling.  Long before the word "haunting" became associated with ghosts, it meant simply  to frequent , in the way teenage kids haunt a park or drunks haunt a bar. A house like the Merchant''s House Museum is haunted, then, by use and by habitude, by grooves worn into the floors and walls--as though you could map out the daily patterns of the people who''d lived here by analyzing these signs of wear. <.