Cellist Mark Kosower saved Zoltan Kodaly's Sonata for Solo Cello, Op. 8, for last when he made his debut in the Washington Performing Arts Society's Kreeger String Series Tuesday night in the Kennedy Center's Terrace Theater. This was fortunate, because it was the highlight of the evening and many patrons (including this reviewer) stalled in downtown traffic would have missed it had it started off the program. What we missed instead was Robert Schumann's Adagio and Allegro in A-flat, Op. 70, a work not without charm but much less of a cello piece. It was originally composed for French horn, but the publisher also made it available for violin or cello, greatly increasing the number of potential customers.

Kodaly's Op. 8 can hardly be imagined on any instrument but the cello, unaccompanied but producing a nearly orchestral variety of sounds. It is an intensive test of a cellist's technique--a test that Kosower passed with flying colors. Its double-stops, glissandi, left-hand pizzicati (plucked while the bow is playing a complementary motif) and high-pitched harmonics (like its echoes of Hungarian folk songs and dance rhythms) have a stylistic and expressive function as well as a show-off dimension. Kosower touched all these bases, too.

His playing was deeply expressive in the slow movement of Beethoven's Sonata No. 4 in C (though his tone took on some rough edges in the fast second movement), and he brought out all the varied colors in Debussy's Sonata in D Minor, ably seconded by pianist Jee-Won Oh. The third Caprice for Unaccompanied Cello of Alfredo Piatti provided Kosower some healthy exercise but was otherwise quite forgettable.