AMBASSADORS FOR FUN. The fabulous Moscow Circus comes to America

A charming horse face peers over a partition, looking expectant. People are walking plaintively about, holding unironed embroidered blouses. You can pick out the acrobats, who are short and lithe, like dancers, with tough, humorous faces.

What will be a glittering arena of magic is now like a construction site. A forklift moves giant blocks of concrete - 10,000 pounds are needed to anchor trapezes and tightropes. People are busy cinching ropes, testing winches that will send the acrobats soaring.

The Moscow Circus has arrived at its first stop in a United States tour, in Worcester, Mass.

The Moscow Circus isn't exactly what we think of as a circus, in that it isn't a company. Actually, it's the Soviet circus; the government pays for the animals and the costumes, and most performers have gone to the official circus school. ``They just call it Moscow Circus when it goes abroad. There's a Moscow Circus in London right now,'' explains an interpreter.

There are 72 permanent buildings devoted to the circus in the Soviet Union. ``It's almost like our old vaudeville circuit,'' says tour producer Steve Leber. ``People go the circus the way we go to the movies.''

This Moscow Circus isn't a ``Big Top'' extravaganza: It is simply 11 of the most amusing and beautiful of the 6,000 circus acts in the USSR.

The circus is famed for its enchanting bear act. A TV camera crew needs something for the early news, so Vladislav Zolkin brings out two bears. One does a little dance, rollicking his whole furry body as he hops from one back paw to the other. He makes small, encouraging, grr-r-r-ring sounds as he hops through a hoop held by Mr. Zolkin, tossing his short, bowed back legs into the air.

Zolkin, a round faced man with a large brown moustache, has a kindness in his manner that penetrates through all barriers of language. Speaking through an interpreter, he says that training bears is very hard work. ``We give all our heart and soul to the animals, that is why they can be so playful and funny,'' he says. ``I start training them very early. I look after them and decide what is their capability. Just like a person might be a dancer and another person might be an acrobat, every bear has its own talent,'' he explains.

Circus people spend their lives striving to create something beautiful, something ever more amazing. Even if you can't understand Russian, when they speak you can feel the intensity and dedication of the artist.

Juggler Gregory Popovitch, now 25, started when he was seven. He is the fourth generation of a circus family: ``They don't ask kids, they just put them in the circus,'' he says. But he has never regretted it, and now he wants to go beyond being a juggler extraordinaire but to ``put some eccentricity in it - to be a funny juggler.''

Finally everything is ready, and the crowd starts arriving: Circuses are for children, and armies of children begin entering the arena, with their popcorn and ice cream cones and sodas. The circus begins with ``Lay-DEEZZ and gentlemen: Welcome to the Moscow Circus!''

The Chernievski acrobats - in red boots and sashes and beautifully ironed embroidered blouses - come out and do double flips on tall stilts. You almost can't believe your eyes; they whirl in the air like giant pinwheels, landing on top of a small wagon. Then the Alexandrovs, in white and silver, do a romantic pas de deux on a trapeze; he standing on his head holding her by one hand, as she hangs below, in graceful, balletic poses.

(There were clowns, of course; what is a circus without clowns? But a clown's secrets must be kept.)

Zolkin's bears come out in modified Russian costume, looking adorable. His wife, Svetlana Mikityuk, a famous antipot juggler (using the feet instead of the hands) juggles drums every which way as if it were nothing. The bears do antipot juggling, too (all four paws count for bears). In one highlight, Zolkin balances a hefty bear on a board on his feet, while the bear catches balls. In another, Ms. Mikityuk, and their daughter, Kristina, pass balls back and forth with their feet through a hoop held by a bear, on a platform being rotated by another bear.

Less charming than the bears but more spectacular are the tigers. There's nothing of ``let me entertain you'' about a tiger. These - all 17 - slouch casually to their places, their coats mellow gold and black under the lights. Some jump through hoops of flame; others play leap frog, as it were, flowing over each other like a single thing. They line up, shoulder to shoulder, and walk around trainer Nikolai Pavlenko, who has a regal presence not unlike his tigers; they lay down obediently.

``Falling soldiers don't die,'' says the ringmaster. ``They become the cranes,'' and the Flying Cranes acrobatic troupe does a ballet in three dimensions. Lena Golovko, the injured crane, falls from the lofty ceiling into the net, with a spasmic arching of the back, expressing the delicacy and agony of the bird. To ``The Ride of the Valkyries,'' flying bodies sweep through the air.

The circus is a profession where courage is required, but even here Tamerlan Nugzarov's daredevil horsemen from the Caucasus are something out of the ordinary. At wild speeds, they tear around the ring as if glued to their beautiful little horses. One man jumps on and off, a knife clenched in his teeth; another, clings to his horse's belly as it leaps through a hoop of sharp knives.

In the dramatic finale, a man with his foot hooked to the saddle lies on the ground as his horse drags him around the ring, pounding hooves within inches of his face. The auditorium is intensely quiet - ``Aw, aw, aw,'' gasped a man near me - until finally the horseman slips nimbly back into the saddle, and the audience starts breathing again, clapping and clapping and clapping.

The Moscow Circus will be at New York's Radio City Music Hall Sept. 14 through Oct. 9, then travels to many other cities. Call 1-800-88-CLOWN.