Opened in 1882 by the O’Brien brothers, these mills initially employed 300 people, who worked a factory with 3000 spindles and 80 powerlooms. ¹ Unusually, it was built in limestone when brick would have been the obvious and most economical choice. ² After a prolonged slump in Cork’s woolen industry caused by the end of the Napoleonic wars (1801-15) and the abolition of protective import duties in the 1820s, the second half of the nineteenth century saw woolen manufacturers resurgent. In 1897, there were 27 factories in County Cork producing woolen goods and the county was now the principal centre of the woolen industry in Ireland. ³ O’Brien’s/St Patrick’s Mills grew throughout this period, expanding to 5,000 spindles and 135 looms in 1897. ⁴ Along with O’Mahony’s Mill in Blarney, O’Briens’ Mill employed 1,100 people in 1904. ⁵ In 1914 O’Briens’ employed 450 workers.

Although milling in Douglas is popularly associated with water power – for example crest of Douglas GAA shows a mill-wheel is next to O’Brien’s mill – there is no reason to believe that a late-nineteenth-century factory would depend on water power. The Tramore River, which ran around the mill, provided water for the steam engines but it was not close enough to the buildings to indicate dependence on water-power. When their close neighbour and competitor, Morrogh’s Mill, opened in 1890, the machinery was driven by a 250HP steam engine, not a water wheel. Both factories produced tweeds, serges and material for clerical suits. Along with a strong home market, St Patrick’s mill exported its products to the Continent, Canada and the United States. ⁶

Since St Patrick’s Mill was opened in the 1880s, the owners could not employ children full-time. Following the Factory Acts (1833-67), children under 8 could no longer be employed and those from eight to sixteen years of age could not work full-time. ⁷ Unlike Douglas’ earlier sail-cloth industry, the woolen factories could not benefit from cheap, juvenile labour. However, any women who worked in the mill were paid significantly less than men for the same work.
The O’Briens sold the mill to Conn Murphy in 1942. ⁸The wool industry in Cork competed successfully into the twentieth century, until the 1970s, when all the large mills – Morrogh’s, O’Brien’s, and O’Mahony’s in Blarney – closed. The last proprietor of the working mills, Denis Murphy, went on to found Swansea Cork Ferries. ⁹ St Patrick’s mill has since been redeveloped as a commercial centre.