For three months last fall, 75-year-old Luke Appling got up in the morning, went to his writing table, reached into two huge cardboard boxes and began opening his thousands of letters of fan mail.

When a man has been retired for a third of a century and has been in the Hall of Fame longer than some ballplayers have been alive, it's nice to discover that, right smack dab in the middle of your old age, you're hot again.

"My wife started to get pretty mad at me. She told me, 'Morning, afternoon and night, all you do is answer those darn letters,' " recalls Appling. "It took me most of the offseason, but I finished 'em around Christmas.

"Must have been about 4,000 letters. The first box full were all real friendly. They'd mostly start off, 'My grandfather tells me you were a pretty fair ballplayer. I saw you on TV when you hit that home run in the old-timers game in Washington. Please send me your autograph,' " says Appling, trying not to seem pleased.

"By the time I got to the second box, it was 'round Thanksgiving and darned if I didn't get cussed out about 150 times. You see, the second box was chewin' me for not answerin' the first box sooner. Oh, I got some snotty ones."

Appling, sitting in the dugout of the Atlanta training complex here, spits his tobacco juice in the direction of the young Braves whom he coaches in hitting. "Guess they think I'm a retired old coot with nothin' to do but answer letters. I've got work to do, travelin' around to Richmond, Durham, Pulaski, Anderson, Bradenton and Savannah to look at these hitters and trouble shoot," says Appling, who is a Braves organizational instructor.

Some players are burdened for the rest of their lives by one event in their careers. A single deed, even a heroic one, can become an albatross, given enough time, enough retellings; who wants to spend 50 years lingering over one split-second from the deep past? Appling is the opposite case. With one swing at the age of 75, "Ol' Aches and Pains" was reborn.

When Appling led off the first inning for the American League with a home run into the left field seats off that youngster Warren Spahn in the Crackerjack Old-Timers Classic last July in RFK Stadium, the former Chicago White Sox shortstop never guessed what he'd done.

Videotape of Appling's picture-perfect swing, his swat a dozen rows into the seats and his comic circuit of the bases (with Spahn chasing him and swatting him in the rear with his glove), became an overnight slice of Americana. The breathless Appling, all ham, feigned a heart attack as he reached the dugout.

"The reaction was, oh, tremendous," says Appling, still stunned. "You know, I got more action and more publicity from that one swing than I did in 21 years in the majors.

"I'm not kiddin' about that. Nobody interviewed us much back then, or put us on TV," said Appling, who played shortstop from 1930 to 1950 with the White Sox, batting .310, winning two batting titles and reaching base over 4,000 times.

The endless retellings of The Tale might burden a man in his prime, but they've spruced up the salty Appling no end; he's stored up a lifetime of stories and opinions that nobody bothered to ask him. Now, he's holding court.

"Oh, no, here comes Luke," says Braves Manager Joe Torre. "I won the pennant and got a two-year contract. Appling hit one home run and got a new three-year deal . . . What nice thing can I say about Luke Appling that he hasn't already said about himself?"

"They've been blasting me ever since I hit that home run," moans Appling delightedly, knowing that when the young stars think you're worth needling, it means you must be twinkling a little yourself. "They told me it probably went 200 feet and the wind blew it the rest. They said, 'By the time you get to camp next season, it'll be 500 feet.' I tell 'em I've got 30,000 eyewitnesses who know I hit it pretty good.

"I loved playing," continues Appling. "Shoot, these guys don't have fun. They worry. They don't even know how to agitate . . . I teach 'em hitting, but I probably spend more time trying to show them how to enjoy the game . . . "

More than anything else in the modern game, Appling is appalled at the deterioration of the personal relationship between players and fans.

"When I was playin', it seemed like every night I was home I was goin' to some (civic or club) dinner for a piece of ham and some peas. I went all the time. Now, they want $500 to cross the street. They're crazy about money.

"The players even get paid to give autographs now," says Appling, aware that some players are paid about $5 a signature by professional autograph dealers--the game's new middle men. "They put on (autograph) shows in Atlanta. They wanted to pay me to sign autographs in my own hometown. I said, 'The hell with that.' I'd just rather not do somethin' like that. I'm gonna eat anyhow. Long as you don't owe anybody . . . long as you got enough.

"A guy that's a millionaire is always tryin' to get another million and that's how he goes broke," says Appling, who claims it doesn't bother him to have missed the game's financial bonanza. His only curiosity, he says, is over exactly how much a team would pay "a shortstop who hit .388," which is what Appling did in 1936.

Appling would, no doubt, have been a hard bargainer. Fellow coach Johnny Sain remembers a story about a game in Detroit when Appling asked the White Sox for a dozen balls to give to a doctor friend. The club said, "Buy your own." Appling, bent on revenge, led off the game and went into his specialty--fouling pitches into the stands.

After about 12, says Sain, the Chicago traveling secretary was trying to get word to the dugout to tell Appling that "his dozen free balls were ready."

Out of Appling's boxes of 4,000 letters, he remembers one in particular because it had a sour contemporary taste. "A fellow sent 50 pictures and I personalized each autograph," says Appling. "A month later, he sent me 50 more with a note saying, 'Please, do not personalize.' The SOB was selling 'em, making a living off autographs. I sent him back a note saying, 'All pictures you send me in the future, I will consider my own.' "

Appling attributes his good health ("I've never been sick or passed out in my life") to his wife's cooking ("I guess it must be good. I ate it") and his chewing tobacco ("They told me, 'Boy, you better quit that,' but I've chewed every day for 60 years").

As for his batting stroke, that needs no tending. "I hadn't swung all (last) summer," says Appling. "Once you've learned how to do it, you can always do it."

This summer, Appling's plans won't change. He'll bounce from town to town, giving tips and trading barbs.

Last year, Appling, who will turn 76 in two weeks, drove all the way from Bradenton to Washington, D.C., for the classic. It's his way. He likes the old modes of transportation--cars, trains or feet, not planes.

"This year," says Appling, who wouldn't miss Crackerjack II for the world, "I'll pinch-hit and probably strike out. The publicity is too great. I can't take it."

Thus will end a magic year that has brought happiness into many of an old man's winter nights.