Apparently in 1863, Beethoven's body was exhumed and examined.

The grave digger gave his account. "I stopped digging when the spade scraped the coffin lid. I cleared away the soil, prised the lid off and there he was, just lying there looking up at me. He had a manuscript in his right hand and a rubber in his left. He was rubbing out all the musical notation note by note.
I said, "Mr. Beethoven, what on earth are you doing?"
He said, "I'm decomposing!"