Vivien Harvey Slater got the National Gallery's piano mini-series off to a promising start last night with a refreshing program of infrequently heard works. Applying buoyant confidence and good-natured vitality to a carefully chosen repertoire, Slater brought her listeners a number of pleasurable surprises.

Who, for example, would have ever considered Czerny, that early 19th-century inventor of seemingly endless technical exercises, an early waltz king? Yet Slater, who is pianist-in-residence at Colgate University, found 23 thoroughly engaging "Valses di Bravura," which reveal Czerny's exuberant, almost naive, delight in the piano's possibilities. Slater's sure rhythmic sense and nicely varied use of touch turned the short waltzes into a balanced series of effective color contrasts that clearly foreshadowed Schumann's piano suites. Her decision to end the set with a Bear Dance as coda added an appropriately droll touch.

From Beethoven, Slater picked the "32 Variations on an Original Theme in C Minor." Though never legitimized with an opus number, the variations hold more than passing interest, as Slater's clearly articulated and finely shaded interpretation pointed out.

Slater also captured the lyrical strength of Berg's First Sonata and maintained a clear path through several Liszt transcriptions of Schubert songs, as well as Liszt's demanding "Mephisto Waltz."

The mini-series continues Sunday with a recital by Raymond Jackson.