The fans in the left field bleachers noticed Rick Dempsey first. Of course, they could hardly miss him, since he was jumping up and down in the bullpen waving a towel around and around his head like a madman.

So, the bleacherites began to roar and wave towels. Next, Dempsey got the attention of the zanies in Section 34 in the upper deck behind first base. This didn't actually take tremendous perspicacity on their part. At that moment, in the eighth inning with the Baltimore Orioles ahead of the Detroit Tigers, 13-0--on their way to a 13-1 win--there wasn't much else to do except let the old eyes wander around Memorial Stadium and its near-capacity 43,938 spectators.

True, there had been plenty of eruptions earlier on this steamy afternoon. When Cal Ripken Jr. and Joe Nolan had hit two-run doubles off Jack Morris in the first inning for a 4-0 lead, the joint jumped. And when Eddie Murray hit a two-run homer in the third off Morris for a 6-0 margin, the 15th Oriole victory in 20 games seemed assured, and that called for appropriate hosannas.

Of course, that five-run fourth inning off hot dog Kevin Saucier couldn't be ignored, even if most of the damage was self-inflicted by the Tigers, what with two walks, a hit batter and a run-scoring passed ball. And, finally, Benny Ayala was properly cheered for his two-run, bases-loaded single in the sixth, all of this assuring Jim (Cakes) Palmer a cakewalk to his 254th major league victory.

But by the eighth, this delightful traditionalist's park--full of live grass and ringing Oriole hits--was calming down too much for Dempsey's taste. After inciting the bleachers, Dempsey now had Section 34 going nuts, too, waving shirts and screaming.

Dempsey, who hates not to play and considers bullpen duty next to solitary confinement, was suddenly in heaven. First he'd point to the bleachers, and the occupants would holler. Then he'd summon the lungs of 34. Then, he'd point north and south--to the right field bleachers and to the grandstands behind home and third--to get them into the celebrating.

Finally, as the poor Tigers, losing for the 13th time in 14 games, looked perplexed, Dempsey had the whole ballpark on its feet--cheering, waving whatever came to hand and, eventually, following his body language in spelling out "O-R-I-O-L-E-S" at thunderous volume.

That moment--with Dempsey doing his Wild Bill Hagy imitation and turning his body into an "O," then a ridiculous "R"--was the official Oriole-watching juncture when the magic energy of 1979 and '80 returned to Memorial Stadium.

The crowds returned here this first summer weekend--128,218 for four games. And the Orioles have returned to form, too. With this humiliation of the Tigers, the Orioles won their third straight game and seventh in nine.

And they climbed to just 3 1/2 games behind first-place Boston in the American League East. Only blazing, bludgeoning Milwaukee, in second place and flying, is playing with similar confidence and authority.

All Baltimore signs are go. For the first time, the club's two young sluggers, Murray and Ripken, are on a tear together. Each had three runs batted in Sunday. Ripken is hitting .377 for his last 17 games and .323 for his last 49; his 42 RBI lead the team and put him at a near-100 pace. His 29 extra-base hits are a half-dozen more than any other Oriole's. Murray is batting .385 for his last 14 games and his May hand injury is gone, at last.

Perhaps the bats were inspired by Ken Singleton, who was given a day off but appeared on the bench on this 90-degree day in a huge fur-lined team parka and wool-lined gloves. "I got to get you guys hot," he announced.

The crowd, biggest since opening day, had an inspiration of its own. When Palmer, who had a shutout through 7 2/3 innings, despite allowing 10 hits, finally permitted an 11th hit and a run, Manager Earl Weaver replaced him. The crowd roared for nearly five minutes, imploring Palmer to come back for a curtain call. When the often offended Palmer did not reappear, it was assumed he was too proud to take a bow for an 11-hitter, too imperious to nod to the same fans who have booed for his injuries and his age.

Then, in a twinkling, Palmer dashed to the top step--barefoot and in his orange Oriole undershirt for a millisecond curtain call.

"Two more minutes and he'd have been on the beltway," cracked Mike Flanagan.

"A nice moment," said Singleton. "Everybody likes to feel appreciated. Even Jim Palmer. Maybe especially Jim Palmer."

Palmer (6-3), who won his fourth consecutive game for the first time since '78, exited quickly afterward. The Orioles' quote sheet had only this cryptic analysis from Palmer: "It was a wonderful performance by the hitters."

The pitcher who replaced Palmer acted as though he thought the ovation were for him. Storm Davis, 20, the youngest pitcher in the major leagues, mowed down all four hitters he faced, overpowering Enos Cabell and Kirk Gibson, breaking both their bats to end the game.

The 6-foot-4, 207-pound Davis had the radar gun jumping at 91 miles per hour--the fastest clocking by an Oriole pitcher all season. Weaver, in delight, kept asking, "How fast was that one?" Flanagan would answer, "83," and then, "That one was 83, again, Earl," until Weaver finally caught on that his short legs were being pulled.

"Earl gets all excited just 'cause some kid throws 91, has a great curve, control, poise and looks like he's the next Jim Palmer," Flanagan said, and grinned. "I told him, 'Earl, we could all throw 91 if they'd give us an ovation like that when we come in.' "

The ovations in Memorial Stadium may just be beginning.