Yesterday was the 185th anniversary of Schubert's birth, not one of those round-number birthdays that are celebrated with so much activity, but one certainly worth a modicum of attention.

Pianist Delia Calapai, who is clearly a devotee of that short-lived master, celebrated the day with a program of two of his loveliest sonatas at the National Gallery last night, the one in G major, D. 894, and the B Flat Major Sonata D. 960. To each she brought thorough understanding and a sense of scope and breadth.

Calapai was at her best when quiet sonorities and a light touch were needed. She was able to select from the elements of the texture those which most directly contributed to the lyricism of the music and to highlight them with a fluid sense of line.

Those sections that were modeled after dances rather than songs, however, the Minuetto of the G Major sonata and the B Flat Major's Finale, were heavier than they needed to be and occasionally awkward rather than incisive, but sensibly, given a choice, Calapai tended toward smaller visions of the music.

Sensible, also, was the decision to program just the two sonatas and then to stop. This was a short program but there was plenty of beauty to savor.