The manuscript of troubled composer Sir Malcolm Arnold’s Seventh Symphony has been found after 30 years missing.

A chance discovery on internet auction site eBay has revealed the mental health struggles of one of the UK’s most distinguish 20th-century composers, Sir Malcolm Arnold. The Oscar-winning composer, who died in 2006, completed his Seventh Symphony in 1973, but the original hand-written score has been missing for more than 30 years.

It is believed that Arnold gave the score away in lieu of payment to a tradesman or plumber after the Court of Protection barred access to his bank accounts due to concerns over his mental wellbeing. Sir Malcolm suffered from manic depression and schizophrenia, and he also struggled with alcoholism. The score was preserved in its published form, but the whereabouts of the original manuscript remained a mystery until two years ago when the item appeared for sale online.

In an interview with the UK’s Daily Telegraph, Sir Malcolm’s daughter, Katherine, described the moment when she finally took possession of the manuscript, which her father had dedicated to her and her brothers. “When we went to get it, it was still in its original box with the tissue paper from...