 John Senior established the family tannery business of Willson, Walker & Co. Ltd. in 1823; it moved to Sheepscar Street, Sheepscar, in 1847.The firm manufactured Spanish leather and leather glue, and made leather artefacts too, for example a leather dressing case, possibly made for the Great Exhibition of 1851.By 1893 it had become the largest tannery in the country.