Samuel Osborn Samuel Osborn (1826-1891) was one of the city's greatest industrialists, becoming Master Cutler in 1873 and Lord Mayor in 1890. The plaque marks the site of his company's Clyde Works, purchased in 1868 from Shortridge Howell and Co. It was here, during the late Victorian period, that the production of R.F. Mushet's self-hardening steel was perfected. This became a Sheffield speciality, making the name Samuel Osborn synonymous with the highest quality tool steel.