Ralph Sampson, 19 years old and 7-foot-4, strolls out of the University of Virginia weight room where he has just put 500 pounds on his shoulder and lifted it from a dead squat.

Sampson is as delighted as any 97-pound weakling who has just discovered that a Hercules may be trapped inside him.Just four months ago, when he enrolled here, the rail-thin, 210-pounder could lift only 225 pounds.

The Cavalier freshman -- a taller version of what Wilt Chamberlain and Kareem Abdul-Jabbar were at the same young and slender age -- is finally filling out and growing up.

Not getting taller, you understand. But beginning the process of learning the amazing things he can do with a body that has finally stopped sprouting and can now be developed.

The relaxed, almost languid Sampson takes one step and leaps. He slaps his hand on the backboard. His head is at the rim, his elbow at the top of the box and his fingertips are 13 feet in the air.

This is Sampson's new toy -- jumping. He has just discovered, since lifting weights to build those spindly legs, that he is good at it. Legend insists that only Chamberlain ever took a silver dollar off the top of a backboard.

Sampson, whose vertical jump has increased four inches in four months, intends to be the second. He's close now.

"Ralph has the potential to be the greatest player of all time," said Terry Holland, coach of the 16-4 Cavs, who host 14-3 Maryland (8 p.m., WJLA-TV-7) tonight.

For the time being, however, Sampson is just a huge and reasonably happy man child who is slowly exploring his gifts while averaging 13 points and 11 rebound for the 13th-ranked college team in the country.

Sampson's freshman year has been a textbook example of blending, a somewhat depressurized initiation into serious ball. Holland regards Sampson, as, at most, a half-finished product, and has constructed his team accordingly.

Jeff Lamp and Lee Raker, those smooth and rugged juniors out of Kentucky's famed Ballard High, must do the outside shooting, and they do, leading the team with 18- and 14-point averages.

Jeff Jones, who thinks he's double teamed in his sleep, must beat the pressure defenses and traps that every team throws at Virginia in hops that the ball will never reach Simpson, Lamp and Raker.

And, 6-6 cocaptain Mike Owens must contribute his fluid knack of doing a bit of everything.

Nevertheless, since May 31, the day when Sampson ended a national recruiting war by saying "Virginia," all those with a sense of history have had their eyes on the latest heir to basketball's pituitary succession.

Watching Sampson is like seeing storm clouds gather. He is a case on which nature has clearly spent considerable attention, but has not yet decided on a final disposition.

Loping onto the University Hall court, Sampson casually picks up a basketball with one hand, then notices a friend who is sweet-talking a girl in the coliseum's upper deck more than 50 yards away.

Winding up like a baseball pitcher, Sampson fires the ball with a casual flick of the wrist. It ricochets around the empty hall's top seats, shocking the surprised couple and bringing wahoos from the Wahoos.

The Cavaliers always seem to have the corner of one eye cocked to see what Sampson is up to.

With the easy, self-contented grace of a man a foot shorter, Sampson flicks a series of fancy layups and syrupy 15-foot jump shots into the basket. His face is alive with pleasure, every shot lighting up his brown eyes and triangular face.

"Like all 7-footers, he thinks he's part guard," said Holland.

"The truth is, that if he were a foot shorter, he'd still have a college basketball scholarship," said UVA Athletic Director Gene Corrigan.

"At first, we wanted to nail him inside the lane," said Holland. "They say the air gets thin the farther a big man moves out from the basket.

"We wanted to increase the oxygen content in our game. We kidded Ralph that we were going to magnetize the lane, then put iron in his shoes so he could not stray too far.

"But we've discovered that Ralph has such a nice feel for the game that we can let him roam. He's a great player 12 feet from the basket. But he has to remember that 20 feet out, he becomes just another player," said Holland.

Just as important to Holland is Sampson's surprisingly easy rapport with his mates.

Sampson tears a piece of tape from his wrist, crumples it in a wad, then throws it into the midst of several Cav players in a three-on-three game. They cuss him cordially.

"Where's the sweat, man?" Sampson teases a teammate who is chugging up and down the coliseum steps. "You're fresh."

"It ain't like that, brother," retorts the player.

"Yes, it is," insists Sampson, laughing.

Sampson has earned the right to jest and jibe not because of his height or even his talent but because of his work.

"Ralph and Jeff Lamp are always the first to arrive and the last to leave," said Holland. "They understand that if you get the lion's share of the fame, you also have to work the hardest or else you'll be resented."

"There are no petty jealousies on this team," said Lamp, the 6-foot-6 guard who led the ACC in scoring last season (22.9) but has deliberately cut his average in this UVA year of balanced scoring and evenly distributed pressure.

"We have places to go," said Lamp. "Ralph can take us there."

"I've fitted in real easy," said Sampson. 'Comin' in, they knew who I was. And everybody knew they needed a center real bad. So, everybody knew the deal.

"The important time to stop problems on a team is before," said Sampson. "If it doesn't start, it doesn't happen."

It is Sampson's way, whether in speech or on the court, to perform in quick bursts. "When competition arises," he said, "I arise."

Sampson's most dramatic impact may not have been in the way Virginia plays but in the way Virginia is seen.

"For the first time, it is not psychotic to root Against Virginia," said Holland. "We have been David so long that it's hard to get accustomed to being part Goliath.

"I know it's only natural to pull for the underdog. I've done it. I'm sure a lot of seudofans want to see us fall on our face just because Ralph came to Virginia.

"Fortunately, the increase in pressure on our team has been minimal. Before, there were 12,000 people trying to fill 9,000 seats. Now, it's 14,000.

"The casual fan who thinks we should win every game by 20 points will never get a chance to sit in our gym and boo us," said Holland. 'Our limited tickets are all absorbed by our alumni, our students and our longtime fans.

"It's a blessing that we don't have twice as big a field house. Joe Blow can't bring his standards to bear on our program.

"When we went to Ohio State, there were eight letters to the editor blasting the coach of a team with only one defeat," said Holland. 'We're not in a hurry to reach that level of expectation."

Or, as Corrigan said, "Our coaches, and most of our fans, understand that our teams have to fit into the framework of this institution. UVA was founded by Thomas Jefferson, not Roy Jefferson."

"The casual fan has become more rabid," said Lamp. "But our hard-core fans are not as discriminating as those at North Carolina. We have people at our games who are actually enoying us, rather than just judging us."

Signs of UVA's big-time blossoming are everywhere. Just five days ago, the Cavs beat No. 3-ranked Duke in Durham, N.C. And, on Sunday, Virginia played its first nationally televised basketball game in history, losing narrowly to Ohio State, then ranked No. 3.

"The last week has proven to us that we belong" said Lamp. "In my first two years, we've almost been in awe of teams with names like Duke and Ohio State."

If Holland wants expectations to grow at a snail's pace, then some of his players think they can't wait.

"I've always been annoyed by Virginia's respectability complex," said senior Owens. "If we lose by a point to Carolina, that means it's a big party weekend here. There's something sarcastic and defeatist in that.

"A lot of us have had feelings hurt by students' attitudes here. On one hand, they don't expect us to win because our academic requirements are high. But, on the other hand, they're very slow to accept us as legitimate students.

"It's easier to play when you're supposed to lose. All you have to fight is the fear of being blown out," said Owens. "But some of us are anxious to feel the pressure of being thought of a s a great team.

"I've been in plenty of reasonably pressure-packed games, but, just once, I'd like to test myself when it really matters . . . in the final four or a national championship. I'd like to see how I'd do."

Sampson is the symbol of Virginia's decision to take that final step from ACC underdog respectability to a new status as a national power.

"We're in a different ball game now," said Holland. "I can feel it in recruiting. Kids we didn't have much chance to get before are listening to us now, because of Ralph.

"But they're noncommittal. They're not sure we're stickers -- that we can stay at the top for years at a time. It's never articulate, but I always sense that they're saying, 'We'll be watching. If you finish in the final four, we'll take you seriously. Otherwise, you're still Virginia.'"

In one sense, Virginia is no longer absolutely Virginia.

"Our recruiting policy has obviously been upgraded," said Owens, whom Holland jokingly describes as "disgustingly honest."

"Coach Holland has more freedom to recruit for first-class talent, regardless of some other factors," added Owens. "The new five guys on the team this season, and the returning players, are very different as far as their social and academic likes and dislikes go.

"The best surprise of the year is how well the old Virginia-type players and the new Virginia players have blended."

That mixture of pre-med (Owens) and pre-NBA, (Sampson) creates interesting coaching decisions.

"It has traditionally been difficult to snap our players back after a defeat," said Holland.

"The easy coaching trick is to slap them in the face by screaming, 'You guys aren't any good.' At most schools, that works automatically, because the players get mad and say, 'We'll show that bum'.

"But here, we have always had to boost our players' confidence. If I tell one of my kids that he's lousy, he'll say, 'Gee, coach, you're right again. Maybe I'm not that good.'

"To tell the truth, we've never really found an answer."

But, to that problem, as to so many others, one Ralph Sampson goes a long way toward constituting a solution.

"Are you serious?" burst Holland when he first heard that Sampson had picked Virginia. "All right!!"

"I just didn't think that something so logical and decent could come to pass," said Holland.

In a basketball world where logic and decency don't always reach the final four against chicanery and larceny, it is clean-skirted, high-principled Virginia that now has the game's most conspicuous treasure.

"Our goal is to prove that all this," said Corrigan, encompassing everything that the Sampson era implies, "can be carried off with style."