He is a novelist, 50 years old, and gay. When he picks up the morning paper now, he reads the obituaries. The deaths are not from old age.

Words cue him: 35 years old. Survived by his mother and two brothers. Donations to the AIDS Foundation.

In the shower he gazes at his feet and imagines the faint purple blush that might spread, and grow, and become the cancer.

His cough frightens him, and he will visit a doctor this afternoon, just for reassurance, just to be told it is only a cough.

"Everyone has lost someone by now," he says. "You have these bleak sessions where all you do is sit around and count off who's got it, or who's going to."

He says he has come to dread the sight of a familiar man now walking the street with a cane. "And he's obviously in pain," he says. "And you stop to chat, and you don't even have to say anything. You know what it is. You see someone on the bus -- and you know. He's dying."

Five years ago, what San Franciscans call "the Castro" had stretched like some great odd dream along a half-dozen center city blocks, its cheerily painted Victorian facades describing a bustling small town composed almost entirely of gay men. Here, among the banks and coffee shops and five-and-dimes that had shaped Castro Street into the most self-contained of neighborhoods, men from across the United States had converged on what looked for a while like a nearly unimaginable melding of community and sexual opportunity. Let loose in the candy store was the central metaphor of the day, implying as it did not only the sudden exuberance of long-repressed sexual possibility, but also the giddiness of perpetual adolescence. For newcomers who took in the corner of Castro and 18th streets in those years, it was the shimmering youth and attractiveness that astonished nearly as much as the sheer numbers of men: Here were the real beauties of San Francisco, flaunting every childhood taunt of sissy with such athletic grace that women here began by way of reflex to assume that a particularly handsome, muscled, healthy young man was probably going to turn out to be gay.

These are the men who now leave San Francisco's hospital wards in wheelchairs, or on gurneys, or in zipped body bags. When they walk, sometimes, they lean for support on the arms of friends or nurses. Every day of every week, another gay man dies or moves to the final stage of his diseases -- the pneumocystis carinii pneumonia that sucks weight from the body until skin draws tight across the bone; or the meningitis that inflames the tissue lining the brain; or the Kaposi's sarcoma that metastasizes, swiftly spreading cancer through the liver and lungs.

The last Rock Hudson news brought no revelation here: Castro Street, in the autumn of 1985, is the territory of men who might all be 75 years old, so familiar are they now with death. The psychologist marks the passing of another year by lifting from his Rolodex the telephone numbers of men who are no longer alive. The city budget analyst, home on visits to his aging father in Wisconsin, finds the two of them made suddenly intimate by the immediacy of mortality. The parks administrator has attended so many funerals that he no longer keeps count, but certain details stay with him still: the open casket, the lone flute melody, the Latin mass.

Men walk the shopping street, or pick up the gay papers, and brace again for loss. The male nurse from the Veterans Hospital is dead. The office clerk from the Diamond Heights Safeway is dead. The realtor, the legal services attorney, the plant shop owner, the artist whose paintings used to line the Castro Street sidewalks on sunny afternoons -- all dead, or gone home to wait for death.

Jon Reed Sims, from Smith Center, Kan., the gifted music teacher who founded the gay chorus and marching band -- dead at 36.

Steven Mark Block, from Seattle, Phi Beta Kappa, University of California and Stanford Law School, the law professor who had helped found the gay-oriented Bay Area Lawyers for Individual Freedom -- dead at 33.

Allan Blair Estes Jr., from Groton, Conn., the theater administrator who created a local gay-oriented theater so popular that only the American Conservatory Theatre drew larger attendance -- dead at 29.

If the most common estimates are true and 70,000 gay men live in San Francisco, then one in a hundred has died so far of the diseases brought on by acquired immune deficiency syndrome. One in 50 has been diagnosed with it. Only New York City, with the death toll now above 2,000, has lost more people to AIDS. And in New York it has been so far a less selective disease, killing a number of intravenous drug users and other victims from the now-familiar "risk groups." In San Francisco, nearly all the dead have been gay men. There is a small-town sensibility that sometimes pervades this place; the whole city seems smaller than numbers or geography might warrant, and it has not taken long for this disease to cut a swath so wide that every gay man in San Francisco has now known someone who died of AIDS, or will.

Every gay man who stands before the mirror in the morning, braced for the first Kaposi's sarcoma lesion, knows he can no longer convince himself that only the promiscuous develop AIDS -- that a single sexual encounter four years ago might have left him with a virus that will kill him.

Every heterosexual in San Francisco has seen an AIDS patient on the street, or worked in an office with someone waiting for diagnosis, or ridden the bus beside men going home to the deathwatch, or read again and again the morning newspaper stories about AIDS and the workplace, AIDS and the psyche, AIDS and the search for a workable vaccine.

The city's public hospital maintains an entire ward exclusively for AIDS patients; the ward is always full, and scatters other AIDS patients around the hospital. A city-funded AIDS foundation uses 22 paid employes and 300 volunteers to offer referrals, social services help and educational materials. There are special funeral arrangements for AIDS victims, special free food deliveries for AIDS patients, special advice services to help men in their twenties and thirties with proper disposition of their estates. Unpaid counselors attend to the grieving, the frightened and the dying; the Shanti Project, as the counselors' organization is called, now runs separate support groups for AIDS patients, women who have slept with AIDS patients, people bereaved by the death of AIDS patients and the people close to AIDS patients who are already feeling what the project calls "anticipatory grief."

This is the face of epidemic. No one knows how this disease will move, or where. But when it comes the way it has come to San Francisco, when it takes hold of a place and shakes it nearly house by house, this is what it leaves behind: "A whole army of walking wounded," mayor's aide Chuck Forester says. "You think -- can there be that many more people? You see the numbers keep doubling, and you think, how many more can there be?"

There are days now, Forester says, when he recognizes with a start some group of men he has not seen in many months. "And I'm so pleased to see them," he says, "because they've survived. They're alive. That's the mentality these days. Something reassuring about seeing somebody who's survived."

The scrapbooks in 5B, which is the now-familiar shorthand for the famous AIDS ward at San Francisco General Hospital, have been filled page by page with the snapshots and greeting cards of men and women who have passed through as patients or bedside family. Small handwritten notes, often clipped to photographs of smiling young men clearly not yet taken ill, add the final information. "Died gently on Ward 5B." "Died at home with his friends, this AM." "Born July 16, 1963. Passed from this life March 29, 1985."

Three pages in one of the scrapbooks contain nothing but handwritten names and dates and places of death. The script on the first page is large and steady, each line spaced at some distance from the next, the writers evidently unable to imagine what might be before them; by the second and third pages, the notes for 1983 and 1984 have shrunk to tiny script that repeats itself line after closely spaced line.

"It just goes on and on," says Linda Maxey, coordinator of the hospital's Shanti Project volunteers. "It's just mind-boggling."

Last August, Maxey says, the counselors took the list to a nearby beach. Name by name, they remembered what they could, and as they had finished with each name, they tossed a flower into the sea. It took the entire day. "Grief processing," Maxey says. "I think we had been drained, walking around with this feeling of this mass of death."

There is nothing immediately striking about either Ward 5B or the AIDS outpatient clinic two blocks away: telephones ring, white-jacketed men and women move easily from hall to hall and opened doors lead into conventional hospital rooms where men and an occasional woman lie back watching television, or awaiting an injection, or talking to a bedside friend. The veneer of normalcy is much prized; General's AIDS staff is carefully screened and works 5B or the clinic only after volunteering for the assignment, and less acclimatized wards even at General have turned up frightened nurses and orderlies who refuse to carry food trays into AIDS patients' rooms.

"It's becoming really clear to me that AIDS is a nursing disease," says Bill Nelson, a soft-spoken mustached nurse who works full-time on the AIDS ward. "Medicine has very little to offer in the way of care, or prevention, or that kind of thing . . . It's sort of like what polio was in the old days. That was also a nursing disease."

He works on the ward because someone has to, because he can help, because these men are so deeply in need of the compassion nurses can offer most and because most of the time those feelings overcome the consuming frustration of caring all day for men who will probably die within the year. Nelson's voice trembles slightly when he talks, and it seems to be more than a private matter; to anyone who has spent a little time in intensive-care clinics and cancer wards, the emotions at General seem surprisingly close to the surface, as though the shell of the weary healer has never been allowed to form.

"This is such a relentless disease," Nelson says. "It constantly is battering the body with new things. It's sort of like sending a patient with an open gaping wound, with no bandage on it, and putting him into a mud puddle, and saying, 'Now, live.' This is sometimes very much akin to a MASH unit, in battle. We bring them in, and patch them up, and send them out to get shot at again."

And it is not necessarily the death that most devastates. "I see them come in on a gurney, half whacked out of their heads and lying in their own stool," Nelson says softly. "To see someone who is constantly having diarrhea, has lost control of both bowel and bladder -- to see him become demented because of some central nervous system process that's going on -- that's hard to watch."

It has been a long time, Nelson says, since he last broke. In the early months of the epidemic he lost two close friends in succession and for a while could not manage the world outside; he called in sick and avoided company until he saw that only therapy would pull him out again. They are familiar by now at General with each other's survival techniques: the clinic nurse who found herself weeping over a story about the non-AIDS death of someone she never knew; the social worker who cries over television commercials; the head physician, himself heterosexual, who spent months regularly calling another AIDS doctor to see whether a cough or an odd skin mark might mean he was going to die of it, too.

Leon McCusick, a therapist who has researched AIDS and gay sexual behavior, has found that to keep from feeling overwhelmed he can only let two AIDS patients at a time into his practice. William Kapla, a family practitioner whose patients are gay, has honed for himself the matter of gently announcing the diagnosis; he still remembers, after he was first obliged early in the epidemic to tell a man he had AIDS, how police called the next morning to ask whether Kapla might identify the body they had found hanged from a tree in Golden Gate Park.

"I've sort of gotten into this time clock of every three months, maximum, I have to get out of here and go someplace, and not think about it, just to keep my own sanity," Nelson says. "And that could be as close as going to Tahoe or something. Someplace where you don't see the word."

He was afraid, for a while, that he might contract it. The fear never entirely leaves anyone who works directly with AIDS; they understand better than most that the disease apparently does not spread through casual contact, but some of their contact, as they draw blood samples and minister to patients, is not entirely casual. "I think my fear has developed into a healthy respect for the disease," Nelson says. "You get sort of a gut feeling about this disease after a while. And you can walk into a crowd, and you can pick out the ones who either have it, or who are heading that way. There's just this look."

The look is gaunt, he says, and delicate. There is a kind of sadness around the eyes. When he worked in open-heart surgery, the nurses came to know something a little like this, the look that made them see that a patient would not survive.

"A very fragile look," Nelson says. "Once you've seen the face of this disease, you can pick it out a mile away."

It feels, the men say, like living through the bombing of London.

"It's like being in a war," says Frank Robinson, a writer who lives near Castro Street. "If you lived in London, you loved your next-door neighbor, and a bomb got his house, and that was that. The grief is self-limiting. And you feel guilty because of that."

"It's like having an entire family wiped out simultaneously," says Bob Ross, publisher of the weekly gay paper Bay Area Reporter. "It's like you're going to a reunion with all your grandparents, your aunts, your uncles, all your cousins, and everything else, and a bomb drops, and they're dead."

"I can cry now," says Forester, who acts as an informal mayor's liaison to the gay community. "Didn't used to be able to cry." The tears finally began, Forester says, in the midst of a conversation about how odd it was that he had not been able to weep. "When I started to crying, it was about the community, and how much was lost, how much harm was done. We were ready to enter the mainstream. We were right there."

Even now, his voice is unsteady when he talks about it.

"And just to have this thing come along," Forester says. "It just reinforces this notion that somehow we're sexual beings, and the notion that we're somehow being paid back. It hits us where we live."

There is more to the London blitz analogy than random and relentless death. A kind of war-on-the-home-front passion has also overtaken hundreds of men and women -- many gay men have been moved by the number of lesbians eager to join in -- who are working as AIDS volunteers. They counsel, they comfort, they deliver hot meals, and some of them simply minister over the telephone to gay men and heterosexuals worried about their own risks of contracting the disease. San Francisco is not gripped with the kind of plague panic reported in the tabloids; the papers run advice about how to make AIDS inquiries in singles bars, and there have been reports of landlords evicting AIDS patients or bus drivers refusing transfers from the hands of gay men, but more common is a general uneasiness about living in the presence of so much death.

"Nobody knows what it will do -- no one knows," says a woman whose name appears frequently in the society pages. "You start to say hello to someone, and I think now people turn their cheek."

The woman had a gay domestic employe recently, and worried about the possibilities of disease; there were personality conflicts as well, but when he prepared a meat loaf for the family, she imagined his hands mixing the meat, was frightened, and threw it away. The domestic was fired soon afterward.

"We have a hot tub, and we had a party Saturday night," says an attorney who has worked on civil rights and women's matters, "and I didn't go in." No gays had been at the party, as far as she knew; the fear was of viruses that even heterosexuals might now be carrying.

She thinks she may drain the hot tub, just to be sure. "It's like that thing from the Bible where the Angel of Death went past all the doors," she says. "And some people had blood smeared on their doors, and some people didn't. So you wonder who it's going to hit."

What if he sneezes on my sandwich? Can someone light a cigarette and pass it to me? Is it safe to use the company shower? AIDS worries have now besieged enough employers that former city health director Mervyn Silverman has begun a series of AIDS talks for personnel managers and employe groups at places like the Federal Reserve Bank, where so many people crowded Silverman's meeting that some had to be turned away and asked to watch it later on videotape. Pacific Bell, the telephone company, devoted two full pages to AIDS in a July employe newsletter and paid for the printing of a 52-page manual on AIDS resources; in the company's preventive medicine and health education office, where one is directed for information about the manual, a clerk is away from the office because his AIDS left him unable to come to work.

"It really is frightening," says Cynthia Elliot, who was so saddened as she watched one of her tenants weaken from the disease, that she and her husband helped cook and care for him until he died. "I do feel like we're in the epicenter of a new plague. And I have to say I'm reading everything I can get my hands on to reassure me that I'm not going to be next."

And steady grief has now settled in for some heterosexuals, too. "I've lost six friends in the last 2 1/2 years," says Silvie Jacobson, affirmative action coordinator for the city's civil service commission. "It's a real horror, and a tremendous sadness . . . and at this point, there doesn't seem to be anything that can stop it. You just have to accept that your hairdresser, or your lawyer, or your dear friend, is dying. And I'm finding it harder and harder to accept."

It is plain by now that AIDS has forced a vast change in the social mechanics of daily life for most gay men in San Francisco; formal surveys have begun documenting the way thousands of men have abandoned a whole array of sex practices now believed to spread the disease. "Until three years ago, I would probably say the gay community was the most hedonistic society on the face of the Earth," Ross says. "It has changed, drastically. So now people are openly discussing death, discussing age, which was never discussed before -- how to take care of the elderly . . . AIDS has forced complete reality on the gay community, which was never there before."

The limits of sexual possibility, so jubilantly discarded only five years ago, now loom close and dangerous. There was a Castro Street joke, in the more libidinous days, about men being like streetcars -- if you missed out on one, another was sure to come down the tracks momentarily. "That kind of sexual tension is gone from the street now," says a gay man in his fifties who has lived above Castro for many years. "You go into the street now, and half the hunks on the street are standing in front of Hibernia Bank hawking AIDS literature, or trying to get you to come work for Shanti, or whatever. It's counterproductive."

What has happened to his own life? "That's easy," he says. "Granted, I'm not 25 years old . . . but I'd circulated, gone to parties, gone to bars, talked to people. No matter how old you get, there's always the possibility of a one-night stand in the back of your head. All of that's almost completely gone. I don't go out in that sense at all, at least not in this town."

The bathhouses have not been closed, and gay bars are still scattered across the town, but gay men here have gradually begun figuring out how to live in a community where sex is so weighted with fear. "There are more people going out bowling," says graphic artist Scott Smith. "Dinners at home. Barbecues in the park. We are a more social community."

And there is a certain element of relief in that, especially for men who are no longer in their twenties and had begun to wonder how long the "party," as so many of them put it, could go on. "I think the compulsion to have sex is gone," Forester says. "People's souls are now a little more important than they used to be. Who somebody is is a more true definition of friendship than what they look like."

Bill Nelson, the nurse who has watched at such close distance as AIDS does its terrible work, still believes in a tender and merciful God. "It's an opportunity for us to look at our values, what is really important to us as people," he says. "I think the gay community was going through puberty, and now we have to really examine what we want. The days of wild sex are over. And now we have to look at people having to sit down and talk to each other. It's a little scary, and I think it's kind of exciting."