The thing about applause machines is that they work. Take Virsky's Ukrainian State Dance Company of the U.S.S.R., which gave the first of three performances at DAR Constitution Hall Tuesday night and is a sterling example of the category. The near-capacity crowd (the hall seats 3,700, far more than any Kennedy Center theater) went wild. By the middle of the program's first half it was into rhythmic applause, and the demonstrations only got bigger and louder as the evening progressed.

There was plenty to go wild about. The performers of this enormous troupe, both male and female, more than 90 dancers in all, are beautiful to look at, beautifully costumed, beautifully disciplined. As to precision of ensemble they cannot have more than a few peers anywhere. Their energy level is astounding, even against the background of the American aerobics and fitness craze. Their virtuosity is eye-boggling, especially that of the men, whose speed, strength, daring and acrobatic prowess leave you gasping.

None of this is surprising about one of the blockbuster folkloric troupes of the Soviet Union. This one, however, hasn't been seen in this country in 15 years, so its return for a 10-week tour -- another byproduct of glasnost and the cultural thaw -- still seems revelatory.

The company was established by Pavel Virsky in 1951, though he began laying the foundations as early as 1937, just about the time Igor Moiseyev, in Moscow, was starting the brilliant folk dance troupe that bears his name. Like Moiseyev, Virsky was trained in ballet, and he drew heavily upon ballet technique in his effort to give folk dance a stageworthy veneer and formal basis. Like Moiseyev, too, he founded a school that became an invaluable breeding ground for the dancers of his troupe. Since Virsky's death in 1979, the company has been led by Miroslav Vantukh, who has perpetuated Virsky's legacy and extended it by building on similar principles.

As mass entertainment the Virsky troupe is dazzling, and it draws an audience -- larger and more general than that for most dance attractions -- that clearly enjoys a glossy, upbeat, fast-paced show. As a dance experience, though, Virsky seems skin deep and ultimately wearying. Though the steps and costumes of the individual dances derive from authentic folk sources, the folk connection comes to seem awfully remote in the context of the company's unremitting emphasis on drill work and pyrotechnics. Regional variations fade into a blur as number after number finishes with a similar bag of virtuoso tricks.

On the whole, the Virsky dancers seemed more spontaneously zestful than their rather mechanically regimented counterparts in the Moiseyev company, as seen in the latter's return to Washington two years ago. But the Virsky repertory doesn't have the dramatic and stylistic diversity of Moiseyev's, and the dancers don't display anything comparable to the grave majesty of the folk troupe from Soviet Georgia (which may also soon return here). Even the music for the Virsky program courted monotony -- except for one brief passage, the whole evening was in duple meter with accented offbeats. One began to long for a waltz or two.

The program divided itself into four types of pieces: the huge ensemble numbers with 40 or more dancers, such as the opening welcoming dance, the "Zaporozhian Cossacks" dance that ended the first half, and the kitchen-sink "Gopak" that was the evening's finale; the all-male bravura numbers, like "The Squat Dance" and "The Sailors' Dance" that were incredible as sheer physical feats; several none-too-effective comic dances, such as those featuring caricatured shoemakers and puppets; and one or two more leisurely, lyrical numbers with more emphasis on the women than the men, providing the evening's most rewarding contrasts. Indeed, from a choreographic standpoint, it was a lovely women's dance, "The Embroiderers," playing with the imagery of interlacing strands of yarn, that gave the program its most endearing moments.

Make no mistake -- the Virsky offers no end of thrills. It's just that not all of them are primarily artistic. The company gives its final performance tonight.