Five unfinished organ pipes, four of which are from Bath where William Herschel lived as a musician until 1781.

This piece is associated with the Herschel family since it features in the catalogue made of all the astronomical material extant at the Herschel house in Slough (Observatory House) in 1924. Although it has been assumed that these were organ pipes, presumably because William was an organist in Bath before he gave up music entirely for astronomy, there is no evidence to suggest he made his own musical instruments.