Richard H. Bales, 83, a composer, music historian and former conductor of the National Gallery Orchestra who organized, promoted and presented Sunday concerts for more than four decades, died June 25 at the health care center at Lake Ridge. He had Parkinson's disease.

Mr. Bales retired from the National Gallery in the summer of 1985 after 42 years as assistant director for music. In that period, he was responsible for 1,786 free concerts in the museum's Garden Courts, and he raised the National Gallery Orchestra from a fledgling ensemble to a level of musical eminence.

As a composer, he wrote more than 35 pieces, and his work ranged from the sacred, "Communion Service," to the lighthearted, "Two Impressions from an Animated Cartoon." Paintings in the National Gallery became the inspiration for his "National Gallery Suites."

A historian and authority on early American music, he composed suites based on music of the American Revolution and the Civil War: "The Republic," "The Union" and "The Confederacy," which were issued as LP albums by Columbia Records in 1960.

A tune from "The Confederacy" was later adapted by Mitch Miller and made the pop charts as "The Yellow Rose of Texas."

A native Alexandrian, Mr. Bales spoke with a gentle Virginia drawl, and his voice was familiar to generations of Washington music lovers as the intermission commentary for live radio broadcasts of the gallery's Sunday evening concerts, initially on WCFM and later on WGMS-FM.

A graduate of Alexandria's Episcopal High School, Mr. Bales took a degree in music at the Eastman School of Music in Rochester, N.Y., then was a conducting fellow at the Juilliard School of Music in New York.

During the summer of 1940, he studied at the Tanglewood Music Center in Massachusetts as a private student of Serge Koussevitsky. Among his colleagues at Tanglewood that summer was Leonard Bernstein.

He returned to Washington in 1941 and took a job at the British Embassy writing and decoding cable messages about shipments of World War II supplies for the quartermaster corps, while writing music in his spare time. Through a mutual friend of David E. Finley, director of the newly opened National Gallery of Art, Mr. Bales was recommended as the composer of the score for the gallery's first publicity film, "Your National Gallery." Finley liked the score, and soon thereafter he invited Mr. Bales to join the gallery staff as director of a concert program that had grown up around weekly Sunday night suppers for servicemen and women in wartime Washington. This project was fast becoming a major effort, and it was taking too much of Finley's time. He wanted someone else to run it for him.

In hiring Mr. Bales, he acquired "one of the Gallery's most lasting personalities . . . composer, conductor, impresario, booking agent and bureaucrat wise to the ways of Washington," wrote Philip Kopper in a 1991 book, "America's National Gallery of Art: A Gift to the Nation."

In his second year on the job, Mr. Bales founded the American Music Festival, which has continued on an annual basis until the present and is the longest-running festival dedicated to the works of American composers. It has included more than 300 world premiere performances.

Mr. Bales, wrote former Washington Post music critic Paul Hume, "has brought the music of every prominent American composer of this century to the Gallery, as well as that of many lesser-known figures. Through the device of inviting singers, various chamber ensembles, and choruses and soloists to the American Festival, Bales makes it possible for audiences to hear the widest possible range of this country's musical thought.

" . . . Bales has led such notable world premieres as that of Charles Ives' First Symphony and the Washington premiere of the Ives Second and Third Symphonies." Ives's First Symphony was performed for the first time at the gallery in 1953, 50 years after it was written.

In 1947, Mr. Bales was interim director of the National Symphony Orchestra. He conducted the National Gallery Orchestra in White House performances during the Eisenhower and Johnson administrations.

His awards included a citation from the Washington Board of Trade, the Award of Merit from the National Association of American Composers and Conductors, and the Cosmos Club Award.

He was a member of the Society of the Cincinnati, the Civil War Roundtable of Washington and the Sons of Confederate Veterans.

His wife of 55 years, Betty Starley Bales, died in 1997.

Survivors include a daughter, Mary Starley Bales Alterman of Alexandria, and two grandchildren. CAPTION: RICHARD H. BALES (1979 photo)