Description Abstract drawing on music a band Jethro Tull (A Song for Jeffrey) from album 'This Was'.Jethro Tull are an English rock band formed in Blackpool, Lancashire in 1967. Initially playing blues rock, the band developed its sound to incorporate elements of British folk music and hard rock to forge a progressive rock signature.'This Was' is the debut album by the British progressive rock band Jethro Tull, released in 1968.