A lost Beethoven quartet movement is receiving its premiere in Manchester tomorrow, after a British academic pieced it together from fragments. Beethoven wrote the slow movement for his op.18 no.2 quartet in 1799 but discarded it in favour of a revised version. The original movement has not survived, but Barry Cooper, a professor of music at the University of Manchester, has reconstructed it from early sketches, filling in missing instrument parts. The reconstruction will receive its first performance by the Danel Quartet, the university's resident quartet, on Thursday 29 September.