It is 10 o'clock at night in the city where America comes to scratch at private places. A strange and wonderful union is about to take place inside Caesar's Palace, in the foyer of the Roman Coliseum. Don King, the emperor of boxing, the man who gives you his life as proof that God made it possible for a former numbers runner and convicted felon to find his way to publicity blessed extravagance, is about to descend on Las Vegas.

His pathway at the Coliseum is lined with elegant black women of enormous beauty. He has added deafening disco music to the steads. Hams, turkeys, whole crabs on ice, individual beef Wellingtons are laid out on long tables against the far wall.

He is about to enter his Doubling Dazzling Pre-Heavy-wei.

He is about to enter his Boubly Dazzling Pre-Heavy-weight Championship Affair, as the publicity sheets describe it, his Largest Ever Disco Extravaganza in the Ball. And nobody, even here, makes an entrance like Don King.

He sails slowly into the Coliseum in a fur-trimmed floor-length purple cape, gold chains draped across his chest, holding a rhinestone-studded crown. His shirt ruffles are lavender. His graying Afro sticks straight up in the air, as usual, as though a hand is going to reach down from heaven and pluck him up.

King bends his head to receive the golden Caesar's Palace medallion (which is worn by the cocktail waitresses, some of whose hairstyles are remarkably similar to King's). He beams regally. He makes a speech. It is a good Don King speech. It lacks timidity.

"It feels simply wonderful to see all these wonderful people that come out, you know, like paying tribute. It's a mosaic of people that form a constellation that epitomizes the melting pot theory of our great nation. This is a happening, an extravaganza, but it's a people event you know . . . from all parts of the world, from the darkest continent of Africa, from Paris, from London, the Indians . . . this is a marriage of sports and entertainment on a glorious oasis in the desert, this glorious Caesar's Palace."

And he sails away.

Jean Claude Ganga, secretary counsel of the Supreme Coucil of Sport in Africa, is one of the guests left standing in his wake. "I am here as a special guest of Mr. Donking," the secretary says in a very thick French accent, and the man standing with him smiles. "He said earlier," the man says, "that when he goes back to Africa there is no way he could explain this. No way."

No Indeed.

Gold watches, white shoes and a great deal of chest hair. Larry Holmes and Ken Norton moving slowly across the disco floor, answering questions, avoiding each other. Redd Foxx shaking his behind on the same dance floor, stepping out for the cameras. Sylvester Stallone looking entranced by his own profile, Chevy Chase (in blue jeans). Sugar Ray Leonard, white-jacketed and quiet, all the way our from Largo, where he's resting up for a fight next month.

And something to reckon with: hundreds of black folk. Here, in Las Vegas, where the black faces still seem mostly to gaze out from the kitchen, where excess is good and greater excess is better and nobody had ever seen this kind of excess with a black man in control.

King gave them that. King has taken entertainment and sports, still the fastest road for blacks after glory, and lit them up together here for Las Vegas to see. Redd Foxx says to Al-Tony Gilmore, a black social historian at the University of Maryland," "Who would have believed, some 15 tor 20 years ago, that black people would be giving a major social affair at Caesar's Palace?"

Susan and Michael win the best-dressed couple prize ($2,500). King said $15,000 in prize money was distributed. Susan and Michael ara professional disco dancers who have white glitter sprinkled on their hair, stuck in their eyelids and apparently imbedded in their skin. "It's called the Darrin look," explains Michael, whose jumpsuit is opened considerably below his navel, adding that the Darrin is his last name. "It's glitter from top to toe. The last three shows I've produced. I've glittered my girls from top to bottom."

The man standing with them is asked if he is their friend. "I own them," he says.

A Martian arrives. He does not spead English, has a white face and antennae and is very fat. In Spanish he says he is visiting from Mexico, and he goes away to dance.

At least 30 people look exactly like John Travolta, but their hair is rumpled.

The room is scattered with "spotters," who are supposed to find especially nicely dressed people for the contest at the end of the evening. "What I'm suposed to do is go over and say how nice you look and can I have your name and of course I'm probably going to do this to people whose names I should know and I'll be tremendously embarrassed," one of the spotters whispers, holding a paper for notes about her choices.

She looks up as a skinny little fellow in a silver lame jumpsuit and glitter-covered hardhat minces through the front door, swinging a purse. The spotter raises her pen and puts it down again, looking uneasy. "I wasn't given very specific instructions as to . . . what to do . . . in every instance," she says.

There is a potbellied gentleman walking around the disco floor in a rallroad cap, a flowered shirt, and a naked woman's legs. The legs are plastic, shod with little red shoes, and have been fashioned into eye goggles, so the feet hook over the man's ears.

Does he dress this way frequently?

"Yes." He is wheezing, "I wear it when I go to bed with a girl and I wear it when I go to bed with a boy. I'm AC/DC."

Later the man comes over and says, "Actually I'm too old to go to bed with anybody, I'm 66. I'm five years past going to bed with anybody, these glasses are quite uncomfortable but I wear them just to attract attention. Like this whistle, which emits a shattering whine and makes people jump. He is still talking after everybody around him has moved away.