The Hague, Jan. 28 (AFP): The adagio of a previously unknown piano concerto by Beethoven, discovered at the British Museum, will get its world premiere on February 1 in Rotterdam, one of the organisers of the concert said.

The 1789 piece found in the museum was no more than a rough outline of the themes but Dutch musicologist Cees Nieuwenhuizen, a Beethoven expert, formed it into a eight-minute piece.

?As far as we know, Beethoven did write a whole concert that included this adagio and disappeared,? Conrad Van Alphen, the conductor and artistic director of the Rotterdam Chamber Music Orchestra said yesterday. ?We have not found any trace that is was ever played before.?

?It is clearly a piece from his youth but not of a first-timer. In 1789, Beethoven had already started work on his second piano concerto,? Van Alphen said. ?The atmosphere of this piece is very close to that of the third piano concerto.? British pianist Ronald Brautigam will play the piece in the performance in Rotterdam.

The piece will be played alongside works by Schubert, Haydn and Mozart.