James Hartley (1811-1886), MP, born at Dumbarton into a WM family, was the nephew of Robert Dall. He worked with his father and brother as a glass-maker. In 1837 he moved to Sunderland and founded the Wear Glass Works, becoming noted for coloured glass. In 1847 he patented a method of manufacturing rolled plate glass for roofing etc. He was on the Sunderland town council from 1842 and was mayor in 1851, 1853 and 1862. He encouraged local railway development and was a director of the N.E. Railway Company. He was Conservative MP for Sunderland in 1865-1868. He was a circuit steward, but left WM for the Church of England in 1853. He died in London.
His brother John Hartley (1813-1884) was born at Dumbarton on 11 February 1813. He went into partnership with his brother after their father's death in 1833, then moved to the Midlands and became a partner in Chance & Sons. In 1839 he married Emma Thorneycroft. In 1841 he joined his father-in-law's Wolverhampton iron-making company, became the head of the firm and a wealthy man. He lived at The Oaks, Chapel Ash, Wolverhampton, became a Justice of the Peace and was mayor of Wolverhampton in 1858 and in 1870 Deputy Lieutenant and High Sheriff of Staffordshire. He gave the site and a donation of £1,000 for the building of Trinity, Compton Road, which became one of WM's 'Morning Prayer' chapels. His retirement to Tong Castle, Shropshire (which appears as 'Pembruge' in E.T. Fowler's novel The Farringdons) in 1855 was a loss to Wolverhampton Methodism. He died in 1884 and his wife in 1909; both are buried in Tong churchyard.
Their second son, John Thorneycroft Hartley (1849-1935), entered the priesthood and was vicar of Burneston, N. Yorks, 1874-1919. He was a notable tennis player, who won the men's singles final at Wimbledon in 1879 and 1880 and was runner-up in 1881.