The quality of effervescence seems to come naturally and effortlessly to Danish dancers, perhaps because August Bournonville, the 19th-century choreographer whose style and technique became the basis of their training, was such a dauntless optimist--unobstructed joy is the most prominent trait of almost all his ballets. In the second of three programs at Wolf Trap's Meadow Center last night, the Soloists of the Royal Danish Ballet assuredly upheld this tradition.

At the same time, the evening bore signs of the wear and tear of the month-long, seven-city tour the 13-member troupe is now completing--the ebullience looked a bit strained, and the dancers' guard seemed to be down with respect to stylistic fine points. Don't get me wrong--there was plenty of wonderful dancing and the general standard was as high as we've come to expect from the Danes. It was only in relation to their own best precedents that the occasion felt somewhat like a letdown.

A number of factors extraneous to the dancing also worked to the evening's detriment. The cavernous Meadow Center, with its poor sight lines, isn't ideal for any dance performance, but it's especially ill-suited to the intimacy of Bournonville and the chamber proportions of the Soloists. And if the troupe wanted to demonstrate its aptitude for modern work as well as Bournonville, the point would have been more effectively made with pieces of greater contrast--even cheeriness can become monotonous. As it was, both non-Bournonville selections--Nils Christe's "Greetings" and Hans van Manen's "Septet Extra"--were on the humorous side, and both were relatively timid as examples of contemporary choreography. Finally, there was the disconcerting alternation of live and taped musical accompaniment.

"Greetings" has two men and a woman (Niels Kehlet, Frank Andersen and Dinna Bjorn) in some moderately amusing clowning involving a park bench. The music consists of Igor Stravinsky's 45-second gloss on the familiar "Happy Birthday" tune, and the same composer's "Circus Polka," written for Balanchine's celebrated elephant ballet--Christe alludes to this briefly by having Kehlet and Andersen dangle Bjorn between them like a pachyderm's trunk. "Septet Extra" spoofs classical ballet, with sight gags ranging from the mock solemnity of the slow movement to the jaw-bopping ending, as four irate ballerinas take vengeance on their roughhousing partners. Both works are only fitfully successful in their attempts at levity, despite the spirited contributions from their casts.

It was good old Bournonville who provided the lion's share of the evening's rewards. Though Lise Stripp danced trippingly and Bjarne Hecht made a sprightly partner in the pas de deux from "The Kermesse in Bruges," the piece loses enchantment shorn of its delightful dramatic context. Far more effective were the scintillating ensemble numbers--the pas de sept from "A Folk Tale," which sported a charming variation by Heidi Ryom and a brilliantly aerial one by Arne Villumsen, and the pas de six and Tarantella from "Napoli," the program's finale using the entire troupe of dancers.

High points in the latter included a wonderfully crisp solo from Hecht, more fireworks from Villumsen and Andersen, and, most winningly of all, a solo by Linda Hindberg that was a model of light, spry, exquisitely molded Bournonvillian style.

Still to come tonight from the Soloists is a final, all-Bournonville program including some rarely seen reconstructions.