Mark Fidrych talked to it. Ray Chapman was killed by it. Ted Williams said that the hardest thing in sports is to hit it. Umpires are instructed to keep their eye everlastingly on it. Roy Hobbs knocked the cover off it. Westbrook Pegler said he heard a rabbit's pulse beating in it.

The baseball -- also known as the horsehide, the old apple, the sphere, the pill, the pea and the onion -- is distinctly American and the focus of a timeless game. It also has been a subject of great controversy this season, a small object causing a storm of debate and speculation. Has the baseball somehow been changed -- made livelier, "juiced up"?

Or this week's issue: Was the baseball filed, scuffed or marked by Minnesota Twins pitcher Joe Niekro? The umpires said it was -- and threw Niekro out of a game after challenging him in the fourth inning Monday night in Anaheim, Calif. An emery board subsequently popped out of Niekro's back pocket, prompting the umpires to give Niekro the thumb and send six scuffed balls to American League headquarters where AL President Bobby Brown suspended the 42-year-old Niekro for 10 days.

Niekro pleaded not guilty, of course, noting he'd kept a nail file and sandpaper in his back pocket for most of his 21-year career. "Being a knuckleball pitcher, I sometimes have to file my nails between innings," he said, adding that he'd always carried the emery board and nail file in his pocket to the mound. "I guess I can't do it anymore," he said. The last pitcher to be suspended was Gaylord Perry in 1982 for throwing a spitball.

No wonder pitchers are going to their wits and files. Suddenly, inexplicably, baseballs are flying out of stadiums at a record rate: 2,513 home runs were hit in the major leagues by the all-star break, compared with only 2,059 last season. A startling upswing. Oakland rookie Mark McGwire (only 23 home runs in the minors last season) is threatening to surpass Roger Maris' record of 61 home runs in a season. The Milwaukee Brewers' home run production has jumped 50 percent over last year. Memorial Stadium in Baltimore, once a pitcher's park, was nothing more than a Homer Dome without a roof the first half of the season. Everyone wants to know if it's because of the ball.

No proof has been uncovered that it's livelier. But the speculation is understandable. The baseball is regarded as sacredly as anything in sports. The mere thought it could have been altered can unsettle people, and not just the game's purists. Who, after all, has the right to tamper with a baseball?

Hitters claim some pitchers mess with the ball all the time -- and they can get into trouble for it. They've scuffed it with sandpaper (the emery ball), and smoothed parts with talcum or paraffin (the shine ball); they've spit on it and cut the cover -- anything for an advantage. Umpires are always inspecting the ball to keep it in its purest state; like bathing a baby in oil, umpires before games immerse each baseball in Lena Blackburne Baseball Rubbing Mud from a secret location in the Delaware River.

The baseball is fixed in American culture: Civil War soldiers played with a kind of baseball; King George V gave Woodrow Wilson one and autographed it. In the novel and film, "It Happens Every Spring," college professor Vernon Simpson discovers a miracle repellent that, when applied to a baseball, causes the ball to avoid contact with wood; the professor becomes a much-needed winning pitcher for the Browns.

What do you do with a baseball you catch at the park? You keep it. Catch a loose basketball and you throw it back. You duck from a hockey puck. But a baseball caught can be a treasure; fans risk physical well-being going for foul balls, and especially fine catches at Memorial Stadium are noted on the public address system: "Give that fan a contract."

What ball makes the sound of a baseball? In "The Boys of Summer," Roger Kahn tells of being asked as a young sportswriter to stand in at the plate against Dodgers pitcher Clem Labine. "Although Labine was not regarded as very fast and was complaining about his arm, the ball exploded with a sibilant whoosh, edged by a buzzing as of hornets. I had never heard a thrown ball make that sound before. It seemed to accelerate as it came closer, an impossibly fast pitch that made the noises of hornets and snakes." Or Thomas Wolfe: " . . . in the memory of almost every one of us, is there anything that can evoke spring -- the first fine days of April -- better than the sound of the ball smacking into the pocket of the big mitt, the sound of the bat as it hits the horsehide . . . "

When a relief pitcher enters a game, responsibility is passed to him in a hallowed custom. He is handed the baseball personally by the manager as if it were a parcel of untold value. A manager usually looks as if war and peace were hanging in the balance, but may be saying nothing more profound than, "Throw the pill, Lefty."

Unlike other balls, a baseball controls its game -- when it comes off the bat at unexpected times in unexpected ways. The batted ball triggers running on the basepaths, a fielding play, an error, a throw, a slide, an umpire's call -- everyone reacts to the ball's flight. Its flight out of the park is a hitter's ultimate accomplishment. When a ball leaves an arena in any other sport, you simply have to get another ball; there's no cause for celebration. Said Heywood Broun, "Whenever a player hits the ball out of the park, I have a sense of elation." The Doubleday Baseball

Scene at the National Baseball Hall of Fame: A small boy stands with his father in front of a glass case containing a raggedy baseball. Asks the boy: "Is this the first ball?" Replies the father: "Well, they're saying it might be."

Prominently displayed on the first floor of the Hall, this special baseball is formally called the "Doubleday Baseball." It was discovered in 1866 in a dust-covered attic trunk in a farmhouse in Fly Creek, N.Y., a crossroads village about three miles from Cooperstown. It belonged to one Abner Graves, and was used to support a theory (untrue) that Graves' friend Abner Doubleday devised the game. The ball is undersized, misshapen and homemade. The stitched cover is torn open, revealing stuffing of cloth instead of the wool and cotton yarn inside the modern ball. It's wrinkled like a prune. Evolution of the Ball

The biggest change in the construction of baseballs this century occurred before the 1920 season. The previous year, Babe Ruth had set the home run record by hitting 29 for the Boston Red Sox. He had done it with a ball that had been essentially the same since 1911. In 1911, the ball had been given a cork center instead of a rubber center, then encased in a one-eighth-inch rubber layer. The number of .300 hitters increased, but a few years later decreased. The baseball was still essentially dead -- but that didn't stop Ruth in 1919.

It was made easier for him in 1920. A livelier ball -- apparently, strong yarn tightly wound made it peppy -- dramatically increased the number of home runs. All the home runs helped take attention away from the 1919 Black Sox scandal; Ruth hit 54 in 1920 for the Yankees. The home run gave baseball its popularity.

During much of the 19th century, the size and weight of the ball changed frequently. In 1845, for example, the ball weighed three ounces. It weighed 5 1/2 to 6 1/2 ounces by 1854. But since 1872, the baseball has weighed between five and 5 1/4 ounces and measured between 9 and 9 1/4 inches in circumference. Baseball and Language

References to the baseball itself have remained an integral part of the game. There's a base on balls, the beanball (another subject of controversy this season), long ball, foul ball, passed ball. There are many types of junk balls, such as a knuckleball. The split-fingered fastball is the latest rage. A phrase has come into vogue: A manager or coach will announce to a pitcher that he's starting a game by telling him, "You've got the ball." Common expressions derive from the baseball: hardball, which is played in Washington politics, and screwball, which can mean a pitch or a person. From the Record Book

Ron Hunt, an infielder who played with five National League teams, holds the record for being hit by pitched balls, 243.

The man who threw a baseball the fastest (officially) is Nolan Ryan -- clocked at 100.9 mph on Aug. 20, 1974, in Anaheim. He was then pitching for California.

The longest throw of a baseball is 445 feet 10 inches by Glen Gorbous on Aug. 1, 1957. He played in three games that season for the Phillies.

Dave Kingman hit a baseball straight up and it didn't come down. He did it at the Metrodome in Minneapolis while playing for Oakland against the Twins, May 4, 1984. The baseball penetrated the netting of the fabric ceiling of the dome 180 feet up, rolled around and stayed there. It was a "ground rule double." Baseball and Washington

For years, a frequently asked question was whether the Senators' Sam Rice caught a baseball when he tumbled into low bleachers at Griffith Stadium in the 1925 World Series. Rice for his entire life (and he lived to be 84) would say only, "The umpire called him out, didn't he?" Eventually, Rice said he would reveal the answer in a letter to be opened after his death. In 1974, he died and the letter was opened. He caught that ball.

Gabby Street, Walter Johnson's catcher, caught a baseball dropped from the Washington Monument. He did it in August 1908 in street clothes after doffing his coat. He missed the first 12 balls dropped, but caught the 13th. A press account said he allowed for a "tremendous wind drift."

The longest measured home run in a major league game was hit not by Babe Ruth but here in Washington by Mickey Mantle of the Yankees on April 17, 1953. The ball went 565 feet and cleared the left field bleachers at Griffith Stadium, ticking the National Bohemian beer sign on the way out. Attendance was 4,206. The ball landed in a backyard on Oakdale Place NW, where a boy retrieved it. A Yankee official, who had run out of the stadium, bought it from him for $5 and presented it to Mantle (good example of baseball as memento). Mantle said he hit "a chest-high fastball." It was hit off Chuck Stobbs, now seen on Maryland lottery commercials. More on the Baseball

The baseball is what all the fans knew Casey wouldn't let go by in "Casey at the Bat."

"It's got a hit in it," Fidrych would say about each baseball he refused to use.

"In the olden days, when I was shortstop for the Gas House Gang, I used to file my belt buckle to a sharp edge," Leo Durocher wrote in "Nice Guys Finish Last." "We'd get into a tight spot in the game where we needed a strikeout, and I'd go to the mound and monkey around with the ball just enough to put a little nick on it. 'It's on the bottom, buddy,' I'd tell the pitcher as I handed it to him."

Hank Greenberg wondered (in 1948) why he couldn't hit Bill Veeck's easy pitches any farther than shortstop when they were having a little fun one day in Cleveland. Then he felt one of the baseballs. Veeck had frozen them. Watching the Baseball

After a third out, a first baseman will flip the baseball to the umpire; a coach will hand it to a pitcher coming out for the next inning; a player, after the last out, can make it roll to a stop at the edge of the pitcher's mound; the crowd will go "oooooh" when it rolls down the backstop screen; if he's lucky, the last pitcher will walk off with it in his glove. What About the '87 Ball?

A spokesperson at the American League office said last week that a test of baseballs conducted by both the American and National leagues at the University of Missouri at Rolla "has just been completed" and that the results will be announced "soon."

While waiting for word that all's well with the baseball, consider the amazement of baseball people this season after watching the flight of balls out of various parks. Some players, managers and general managers have suggested the baseball is different this season, but no one has expressed it quite so succinctly as Yankees pitcher Tommy John. "After all this Oliver North stuff is over," said John, "Congress should take a look at the ball."