The firm begun by Henry Hughes in the 1830s became H. Hughes & Son in 1875, and H. Hughes & Son, Ltd. in 1903. After a merger with Kelvin, Bottomley & Baird, Ltd. in 1947, it became Kelvin & Hughes, Ltd. The "HUSUN" trademark was in use by the 1920s.
Ref: Gloria Clifton, Directory of British Scientific Instrument Makers
1550-1851 (London, 1995), p. 144.