A LETTER in the newspaper from a lady in Ohio. She's written to Percy Ross, the Daddy Warbucks of the Modern Age, the Miss Lonelyhearts with the dough. "My dear Mr. Ross," the lady begins, for clearly, she is refined, "I am 73 and give my 86-year-old sister intensive care 24 hours a day. She is an epileptic, who can't talk, walk and can barely see . . . Our combined income is $665 a month, including food stamps. I need my roof fixed badly, it leaks from the upstairs into the first floor . . . The only money we have is about $400 I saved to bury us . . . I'm sure you're one of God's angels. Will you please help us?"

The naivete' of the lady! To think she will get something for nothing! From a newspaper columnist, no less! Good lord, they're lucky if they can pay the rent.

But wait a minute, what's this?

"I have contacted Dick Baker of the Baker Roofing Inc. in Columbus and he is going to do the work and send me the bills," writes Percy Ross. "Hang on to your savings.

"Perhaps I can answer your prayers . . . although I'm not one of God's angels," it says.

Percy Ross. The Dear Abby of The Downtrodden. Millionaire Philanthropist who vowed to give it away before he died, and is doing, at the age of 66, pretty well. Spent thousands and thousands on a party for disadvantaged children the night before Christmas 1977, and before they went home, provided each with a brand-new bike. Threw a $25,000 steak and champagne party for the bellhops at Minneapolis Airport, who treated him just as well when he made his millions as when he was down and out. When he goes on a trip, he carries a few hundred in silver dollars to give out: his motto is Sharing is Caring.

Then there's the column, Thanks A Million, syndicated by the Register Tribune Syndicate in 80-odd papers. Advice. Better yet, cash. A woman on public assistance and her handicapped daughter without running water in Tennessee? Off goes the check! An elderly woman, the candy lady of Seattle, who's been dispensing goodies to the children for years, now in a wheelchair, and the neighbors want her to get a remote-control TV so she doesn't have to get out of her chair? Ross will go out to Seattle and buy the TV himself. Himself, himself!

Not out of a hat, not via a pumpkin, not even out of a private jet. Those high living flamboyant days, those days of the color TV in the shower, have been toned down for Ross, he insists; even if he still wears the Gucci loafers and drives the limo once owned by Howard Hughes. A tuition check for the high school dropout who wants to better herself and take the high school equivalency test; Ross is a sucker for self-improvement, out goes the check. A 92-year-old woman who took her driving test at 72, but can't afford to fix her car, and she has to visit friends at the nursing home; out goes the check.

Oh, there's them that's turned down, of course; the idle dreamers, the loafers, looking for an easy way out. But for others, there will be the money, the common denominator only that it will change a life. And this money is the most suspect thing in the universe, the free buck.

Naturally, there are those who decline to carry the word. Ross' hometown paper, the Minneapolis Star and Tribune, the only major paper in town, does not run Ross' column, and some in town question his motivation.

"Percy Ross is a publicity hound from the word go," Minneapolis Star Tribune columnist Robert T. Smith told People magazine. "If you're going to be a real philanthropist, you do it quietly and get your reward in heaven."

Ross' rules, which have a tendency to rhyme (Sharing Is Caring) are absolutely the opposite.

"He Who Gives While He Lives, Knows Where It Goes," he says.

As for his needs, it is entirely possible that among them, publicity is only a small part.

Meanwhile:Dear Mr. Ross:

I am 71 and never sleep well in this high crime area in Brooklyn . . . I'd feel a lot safer if I had steel bars on my windows--Mrs. L.O., Brooklyn Dear Mrs. O.:

I hope you sleep better. My check is in the mail.

What hot copy precedes Percy Ross! He sits in a hotel room with a Detroit reporter and throws silver dollars into the air, to glory in that unnatural, but in his case quite real, phenomenon, a shower of money. He rode in the Minneapolis Aquatennial Torchlight Parade as Honorary Swede of the Year five years back and, from the back of a Lincoln Continental, flung $16,500 in silver dollars to the crowd, trying for a giveaway rate of $5,000 a mile. His staff is all female. On the phone to Jimmy the Greek, it's "Jimmy Baby"--"Percy Baby."

So it's something of a surprise, when Ross, age 66, comes into New York to promote the newspaper column and appear on "Late Night With David Letterman," to find, in the hotel lobby, a man quite subdued, perhaps even preocuppied with some sorrow. The build is slight, the voice is quiet, he wears a quiet blue sports jacket, albeit with the silk pocket scarf and Guccis; he asks if it's okay if he's interviewed in the lobby; his wife isn't feeling well, he'd rather not disturb her upstairs. He is not covered with jewelry; he doesn't call anyone "baby." You know, only because you've seen the stories, that there's a medallion under the shirt that says Percy Ross--Millionaire; just as you know, only because he tells you offhandedly later, that the white strands of softly waving hair on top of his head are transplants.

Does he still have the color TV set in the shower?

"That was in the good old days," he says, his voice as pleasant and friendly as a Fortune 500 exec. "I've changed. It was just a thing I always wanted . . . I was living out my fantasies." He laughs, a little at himself. "The steam in the shower clouded the screen, so that I had windshield wipers installed."

And the cars, the nine cars to match the colors of his 200 suits?

"I've still got the cars," says Percy. "Generally, I'll use the limo only if I'm giving a talk at one of the schools, to take the kids for a ride, or if I have guests . . . I'm down to about 100 suits . . . I enjoyed my life, I'm pretty much back to normal now . . ."

A few days after the first discussion he is asked in a telephone conversation to comment on a charge of possession of hashish, which he was acquitted of two years ago, and he is considerably less affable.

"I'm only going to give you one sentence on that," he says. "I can't waste my time thinking of anything negative; what was found was not hashish and the case was dismissed." Pressed to explain further, he threatens to hang up, while a loyal assistant, Connie Hanson, interjects, "That was all started by a vindictive female employe, who was angry that Mr. Ross was giving money to other people and not to her . . . He was charged . . . and it isn't true." Taking Care of Business

The ups and downs of Percy Ross: it's no wonder the New York literary agents and Los Angeles producers are after him to do the story of his life. Born poor, the son of immigrants, twice rich, twice broke; buys a plastic-bag factory in '58 for $30,000, sells it 11 years later for $8 million. Gives $2 million each to his two sons and wife ("I didn't give it to her, she earned it," he corrects), cleverly invests the rest. No one now knows precisely what he's worth; the figure $20 million circulates only because a Newsweek reporter put that to him once as a guess, and Percy shrugged, and so it remains in the files. It's enough, at any rate, to do what he likes with it, and what he likes to do is give it away.

He's been asked why so often that his reply, accompanied by silver dollars for reporter and photographer, could probably be made in his sleep.

"What am I going to do with it after I'm gone?" he says. "My family is all taken care of, I could leave it all to different organizations, but I enjoy spending it while I'm alive. My motto, of course, is 'He Who Gives While He Lives, Also Knows Where It Goes' . . ."

They say if you were a true philanthropist, you'd give it away quietly, without hogging the limelight; that you could go off and build a hospital or something without this undignified spectacle of flinging money into the street; or bringing in disadvantaged kids the night before Christmas and making sure the TV crews are there when you give it away.

An unflappable shrug from Ross.

"I enjoy giving," he says. "I want to be there when I give. Just like parents want to be there when they give a present on Christmas morning--they don't go in the other room. I want to see the faces of those kids when they see those shiny new bicycles. That was a dream of mine ever since I was a kid, to help as many poor kids as I could."

That particular party: One thousand and fifty disadvantaged children, in Minneapolis, gathered in a high school auditorium. At each table, as "kind of a subconscious lesson," two policemen, as counselor and friend. He had policemen opening gifts for kids, he had policemen taking kids by the hand to the bathroom, chuckles Ross. The room is divided by a curtain. End of the evening, Percy has the kids stand up, backs to the curtain. "I said, 'You all stand up and keep looking at me'--I had 1,050 kids facing me." When the curtain goes up, he has the kids turn around. They see the 1,050 shining bicycles and they start screaming, yelling, knocking over chairs to get to their bikes. He can't describe it. He cried, that's for certain. Those kids and their bicycles. Because of him, Percy Ross.Dear Mr. Ross:

I am a young pretty girl of 16. No 9-to-5 jobs for me. I'm going after a rich husband. I'm asking you to find out from your wife how she landed you--L.L., Pennsylvania Dear Miss L.L.:

Actually, my wife landed a poor man and helped him become rich.

It was for a reason, by the way, Percy Ross invited 1,050 children to his bicycle party. One thousand fifty has significance in Percy Ross' life. He bets "10" and "50" at the tables in Vegas; at his parties, he often invites 1,050 guests. This is the significance: when he was a kid in Laurium, Mich., Upper Peninsula copper country, he opened his mason jar savings bank and counted 1,050 pennies. A number that remains with him. Which was, in addition, insufficient to buy a bike.

He was a poor kid, no question. His father was a Swedish Jewish immigrant who had come to New York and left it, finding the going rough for a man who spoke only Swedish. He relocated in Michigan, where, if he was a minority as far as religion, at least he was among people to whom he could speak. There was marriage, and three sons, the oldest of whom was Percy. The father's profession was junk man, or, often, dealer in used goods. They bought old potatoes from the farmers and brushed off the dirt after the long winters in the bin and brought them into the city to be made into potato chips; they bought and rebuilt batteries; Percy sold eggs. The second son, Bernard, was considered the scholar; Percy tended to follow his father in business. His father did not do well.

"I never had clothes like the other kids," Ross says quietly, his hands folded across his chest in a protective way he does when he talks about his past. "We lived on the outskirts of town, near something called The Slop Ditch . . . it was an open sewer . . . once I fell into it . . ."

As for what he wanted, he answers without hesitation.

"I wanted to be rich," he says. "Because I remembered what the other rich people in town looked like . . . they were the copper barons, the copper kings, the Ryans, that was a big name in Montana . . . they rode around in their big cars; they had their big country clubs . . . in fact, I went to a country club, wasn't more than 8 or 9 years old, tried to shine shoes for some of these rich people, a nickel a shine; you know they wouldn't even let me through the door. I knew I looked good, my mother dressed me up neat and clean, Dad drove me up there in his wagon, they wouldn't let me in the door . . . I don't know why, maybe because I was Jewish, maybe because I was too poor . . . to this day, they invite me now, I won't set foot in that door . . ." The Beginnings

It was a life with some tragedy: His brother Bernard drowned when he was 16; years later his remaining brother would die at The Battle of the Bulge; his body, says Ross, is still "over there." Ross graduated from high school, moved to Duluth, Minn., started a scrap metal business. He met his wife at the tables in Las Vegas. She was in a maroon dress, beside Clark Gable, and such a knockout Ross assumed she was a movie actress. He was trying to roll four, a difficult point. "If I make it, will you introduce me to your date?" he asked.

She turned out to be a vacationing Jewish girl from Duluth. They married. They had two sons. He made his first fortune in the fur business, then lost it; made his second as an auctioneer handling government surplus. He broke the law once, as a very young man, dealing stolen copper, but he confessed immediately and charges were never pressed. In '58, he bought Poly-Tech, a small plastic-bag manufacturing plant in Eau Claire, Wis. Five years later, he was $500,000 in debt. He pawned his wife's furs and, working with one of his sons, a business student, was able to turn the business around. Up, down; up, down! A friend of 25 years, Mrs. Eddie Cohen, says that even when he was down "he would never dwell on it; he was an up person." But Ross, recalling the hard times from the inside, says there were times you couldn't help but feel bad.

"When you call people and ask for help and they don't answer your phone calls, when you see them darting into doorways because they're afraid you're going to ask them for a loan, when you're not invited anywhere . . ."

That wasn't his style. During one of the up periods, he bought his wife a fur, and when, during a get-together with six other couples who were their closest friends, the women admired it, Ross said that if he got rich, he'd buy every one of those ladies a fur.

He got rich.

They teased him about it.

"When are you getting us our mink, Percy? It's getting colder every year," Mrs. Eddie Cohen says.

Ross calls a furrier friend in New York. He has him send in 50 or 60 furs. He hires a country club for the night, for just these six couples who have been his friends for life. Because he has worried a bit about whether the husbands might be offended, he has determined to get them all plastered first. He gets everybody plastered. He tells the band to strike up "Promises, Promises." He stands up in front of the curtain--oh, yes, Ross likes that curtain--and says, "Girls, 14 years ago, I made you a promise." "Who you kidding, Percy?" they yell.

The curtains fly open.

A half dozen models start parading 50, 60 coats. The women are screaming. For the Fabulous Mr. Moola; for the once-in-your-life real fairy godfather; for him, Percy Ross.Dear Mr. Ross:

I am unhappily married and planning to get a divorce in order to marry a marvelous man I met while skiing last winter. Could you help me ($500 for the divorce)? Could you also include an extra $500 in case the new marriage doesn't work out?--R.P. Dear R.P.:

You are not taking marriage seriously enough! Sorry no money.

So now there's the newspaper column, and an average of 4,000 letters a week. There are the visits to schoolchildren, to whom he gives the I-did-it-work-hard-you-can-do-it-too pep talk, followed by the ride in his limousine. There are the people who get his number and call him from England and Africa. There are the hard-luck readers he will attend to himself; the junk dealer in Fargo, N.D., who needs a truck; well, it's clear why he feels close to that one; the lady in Seattle who's raising her dead sister's children, as well as her own, and feels they can scrape by if they get a cow; Ross will go out himself--he used to be an auctioneer, after all--and buy her a cow.

As for what he himself is missing, what Ross would request if he could write to some fairy godfather like himself; he can't really say.

"I wish I had another 66 years," he says, with a laugh. "Really, I've been pretty lucky. I have a wife who loved me and put up with me, I have a family . . ."

And yet he seemed somewhat sad at the beginning of this talk.

"I'm sad a lot of the time," he says. "I could tell you stories, but you probably wouldn't believe it . . . you don't know what poverty is. Or what buying 25 cents worth of junk was like; weighing out eight pounds of junk, 16 cents a pound in somebody's kitchen, I don't know if the word exactly is 'degrading' . . .

"It was hard," he says. "I was called 'Sheeny,' 'Christ Killer,' 'Goddamn Dirty Jew'--by some of the grandparents of the kids I buy bicycles for now. How I felt--I don't know how to explain it--how did Shylock feel? He knew he was an outcast in the community, and yet there they were, doing business with him. There we were in that old truck . . .

"Now I'm offering hope," he says. "I'm showing all rich people aren't selfish; they aren't bad; I'm saying I was poor once, I worked hard, I got rich, now I'm having a terrific time, so can you . . ."

And so what if the rich people snub him? And so what if the Mellons and the Rockefellers care to give theirs away building hospital wings and such? He, Percy Ross, will personally fly out to Seattle next week and buy that milk cow. Because he, Percy Ross, wants to have "the satisfaction of delivering that cow to that lady." And if she asks him to stay to supper, you can bet he will stay to supper. To bask not in the publicity, but in the appreciation, the thanks, the respect, of a woman who will look at him and see not a "Christ-killer," not a poor boy left standing outside the country club or a fellow in need of a handout, but the Great Fairy Godfather, the Caring Rich Person, the Generous Human Being, the wonderful Percy Ross.