Last night's Julliard Quartet concert at the Library of Congress was dedicated to Albert Moglie, who for almost 50 years has doctored and maintained the library's rare stringed instruments, including the Stradivari upon which the quartet plays. Referring to Moglie as "a kind of savior to all of us, one of that rare breed who understand what makes great instruments speak," first violinist Robert Mann presented the 90-year-old master violin-maker with a folio containing 10 large color photographs of the instruments and a special citation.

Like an old-fashioned physician, Moglie over the years has routinely arrived, black repair bag in hand -- the instruments are not allowed to leave the library -- to give the instruments a checkup before and after every concert. He has also, as Mann related, responded to many an emergency, applying his special art to cure an instrument's sudden hoarseness or squeak.

The Stradivari were clearly in the best of health, as forceful playing by the quartet testified. Violinist Earl Carlyss, joined by pianist Claude Frank, opened with a lyrical Mozart sonata. David Diamond's tightly written Tenth String Quartet and Brahms' dense C-Minor Piano Quartet received strong, almost fierce, performances.