Thomas Miller (1811-1865) became chief partner in his fathers thriving cotton spinning business, Horrocks, Miller and Company in Preston.

The mills owned by the company employed hundreds of local people, and Miller was famed for the comparatively good treatment of his staff, including the introduction of pensions and compulsory education for children. Upon his death in 1865, his son, Thomas (or Tommy) Horrocks Miller took over ownership of Singleton Hall.