Jews-harps are capable of producing melodic, atmospheric and rhythmic sounds. There are a number of misconceptions or preconceptions relating to the sound produced, which, given its main function is to be a musical instrument, is critical to its usefulness. Many of the works that are analytical focus on the acoustics of the instrument. The jews-harp is briefly mentioned by Francis Bacon in Sylva Sylvarum, first published in 1626, under the section 'Natural History, Experiments in Consort touching Sounds; and first touching the Nullity and Entity of Sounds'. Graham Lawson has also identified jews-harps at a number of sites, one of the most interesting being at Fast Castle, Berwickshire. The Pitt Rivers was also very influential in the work of a further researcher into acoustics, John Wright. In 1966 Wright began to analyse their collection in some detail and was asked by the then curator, Bernard Fagg, to make a recording of their pieces.