1867-1944,active 1890-1920s, inventor; scientific & medical instrument maker, Austrian Castagna, Ludwig 1867 - 1944
active 1850s-1905, mathematical, optical medical & nautical instrument maker, Greenwich, England Hudson & Son
active ?1920-?1940, medical instrument maker; surgical instrument maker, Paris Collin, Mathieu & Gentile
active 1957-current (2009), medical instrument maker, London, England Schuco International London Limited