HENDERSON, Nev. — Tom Stevens sat at a Starbucks in this Las Vegas suburb and watched his grandfather, Babe Ruth, cavort across the computer screen.

“I haven’t seen anything like that,” Stevens said. “It doesn’t mean that there isn’t other stuff out there, but I haven’t seen it.”

There are so few moving images of Babe Ruth that even Major League Baseball’s monstrous archive contains less than an hour’s worth. The bulk of Ruth footage may, in fact, still be buried in basements or stashed in attics.

One recent discovery, from a cellar in Illinois, might be unlike any other, showing Ruth in his prime and shot from close range, sitting atop a pony while wearing a child’s cowboy hat and muttering into a home movie camera, as a boyish Lou Gehrig, who never had children and was known for his dignified demeanor, held children and framed his smile with big dimples.

Also on the eight reels of 16 mm film recently found in excellent condition in the cellar are 3 1/2 minutes of Ruth and Gehrig wearing the uniforms, but not the caps, of their barnstorming teams. The film is thought to have been shot with a high-end home movie camera in or around Sioux City, Iowa, on Oct. 18, 1927 — 10 days after the Yankees completed a four-game World Series sweep of the Pittsburgh Pirates.

That season has special meaning in baseball annals. The 1927 Yankees, with their Murderers’ Row lineup, finished 110-44 and might have been the best team in major league history. Ruth, 32, hit 60 home runs that year, a record that stood for 34 years. Gehrig, 24, hit 47 home runs — more than anyone to that point other than Ruth — and was the American League Most Valuable Player. His consecutive-games streak was in its infancy.

With so much of baseball’s history predating the digital age, some of the sport’s best players and moments were captured mostly through stories and still photographs. But check the attic: The barnstorming footage is the latest in a growing string of unearthed film treasures from the Ruth era.

In 2009, Major League Baseball received a few seconds of video of Ruth playing right field at Yankee Stadium, something archivists had not seen before. Last week, the MLB Network unveiled newly received clips thought to be a sort of instructional film from 1924 with Ruth, Ty Cobb and Walter Johnson.

Last year, the only known full copy of the television broadcast of Game 7 of the 1960 World Series, featuring Bill Mazeroski’s game-winning home run that pushed the Pirates past the Yankees, was found in Bing Crosby’s wine cellar.

Such discoveries, especially those with Ruth, tend to be grainy and shot from a distance. He is often identifiable only by uniform number, his barrel shape or his famous swing.

Not this time.

Standing outside a large brick home or public building in the dappled shade of large trees, Ruth and Gehrig posed and chatted among a dozen or two well-dressed men, women and children. There is a rare close-up of Ruth without his hat, talking to the camera. Behind him, Gehrig held a small boy and gave him a peck on the cheek. Christy Walsh, who managed the tour and was considered the first major sports agent, is seen in a few seconds close up, too.

At one point, Ruth recoiled from a backpedaling pony and laughed. He pulled the cowboy hat off a young boy dressed in Tom Mix-era cowboy regalia and mugged for the camera. The portly Ruth climbed aboard the pony, which looked barely sturdy enough to support him.

“It’s a slice of the man, not the myth, at the pinnacle of his career,” said R.C. Raycraft, who bought the films for an undisclosed amount from an antiques dealer who purchased them as part of an estate sale. “Lou Gehrig was still a kid, and Babe Ruth was acting like a man-child.”

Raycraft, whose family runs the 3rd Sunday Market, an antiques show in Bloomington, Ill., said he had not decided if he would sell the film. He may donate a copy to the Baseball Hall of Fame in Cooperstown, N.Y., if the Hall thinks it can be put to good use. Neither the Hall nor Major League Baseball has seen the film, but each is interested.

It is uncertain just how rare or valuable the film is, but a photograph of Ruth’s and Gehrig’s barnstorming teams, the Bustin’ Babes and the Larrupin’ Lous, from a game in Des Moines and dated Oct. 17, 1927, sold in December for $33,000. The alliterative nicknames of the teams were meant to evoke the heavy-hitting styles of the two sluggers.

“The barnstorming tours were heavily covered events,” said Jim Gates, librarian for the Hall of Fame. “It was a big event. I have not personally seen a lot of footage of the tour, but I never really went out and looked for it, either.”

Barnstorming tours were common in the Ruth era. The 1927 tour began two days after the World Series and consisted of 21 games strung from Providence, R.I., to Los Angeles. Local schools closed for the occasion. Thirteen games had to be called early because the mobs disrupted the action. (“Every time a fly or grounder went past the infield there was a race between the outfielder and the spectators on the fringe of the crowd,” The New York Times reported from one game.) Ruth, who occasionally pitched, had a .616 batting average on the tour and hit 20 home runs. Gehrig batted .618 and hit 13 homers.

The tours were a way for big-name players to cash in on their popularity. Ruth earned a $70,000 salary from the Yankees in 1927, and he matched it on the cross-country tour. Gehrig, too, reportedly doubled his $8,000 salary, though he was about to get a new Yankees contract paying him $25,000 a year. The men signed thousands of baseballs, tossing them to fans in the stands and occasionally from their train as it rolled through towns across the country.

The Sioux City Journal newspaper of Oct. 19, 1927, described a chaotic scene at the previous day’s game. About 5,000 people crammed into the minor league park, and “2,000 youngsters became so unmanageable in their desire to get a close-up” that the game was called early in the ninth inning.

During a rush of fans in the seventh inning, “Lou probably saved the life of a little fellow who was trampled to the ground in the rush by carrying him across the diamond to safety,” the report said.

Perhaps that explained why so much of the 3 1/2-minute film of Ruth and Gehrig, probably taken at a postgame event for special guests, showed Gehrig paying so much attention to children.

Raycraft, 43, from Normal, Ill., produces law enforcement videos but has had a hand in his family’s series of books on antiques and collectibles. A dealer at the 3rd Sunday Market asked him if he was interested in “home movies” of Ruth and Gehrig.

“It instantly got my attention, simply because he said they were home movies,” Raycraft said.

The eight reels include aerial shots — rare for 1927 — of farmland and film of Nebraska football games. Attached paperwork describes the contents and said the films belonged to a family in Le Mars, Iowa, which is about 20 miles northeast of Sioux City.

In Nevada last week, Ruth’s grandson, now 58, watched a portion of the film a few times. Stevens is the only child of 94-year-old Julia Ruth Stevens, one of Babe Ruth’s two daughters (one each from two marriages) and the only one still alive.

“My mom is the best living authority on him from a personal standpoint, certainly,” said Tom Stevens, who accompanied his mother when she threw out the first pitch at the last game at the old Yankee Stadium — the House That Ruth Built — in 2008.

But Stevens is a Ruth encyclopedia, too, and a close guardian of his grandfather’s reputation and myth, as passed from his mother.

“That’s really pretty good video of him,” Stevens said. “But it’s not remarkable that he’s out and about with people. He commonly did that. That’s part of the reason people felt as affectionately about him as they did.”

Stevens watched and talked. He was born four years after Ruth died in 1948, but he enjoyed the portion of the film showing Ruth playing with the children.

“I think he was most comfortable and most at home with kids,” Stevens said. “They say he was just a kid at heart. And I think that’s true.”