Brown, John Shaw (1822–87), linen manufacturer, was born 12 April 1822 in Waringstown, Co. Down, son of John Brown; his mother's name was probably Catherine Shaw. He was educated for a career in one of the professions; but on the death of his uncle James Brown he took over the family linen manufacturing business, then at a very low ebb, though in 1834 the bleachgreen had been capable of producing 10,000 pieces of linen a year. He built a linen factory at Edenderry, five miles south of Belfast, which was one of the largest in the area; all the power looms and other machinery were made by the company's own craftsmen. He was able to return the business to profit in a remarkably short time, and entered into partnerships, first with a Mr Magee and later with a Mr Liddell; with the latter he opened a linen warehouse in Belfast. The business was in the name of Brown & Liddell till 1866, when the partnership was dissolved, and the firm of John S. Brown & Co. (later John S. Brown & Sons) established a large warehouse in Bedford St., where seventy people were employed to deal with huge orders from all over the world. The firm's contracts to supply sheeting and damask for table and bed linen, to hotels, railway companies, and other concerns, were said to be the largest in the United Kingdom, and its trademark – a woven-in shamrock – was well known. Its products won prizes in many international exhibitions, and the company's reputation was enhanced by the paternalistic care taken of employees in Edenderry, Lurgan, and Belfast.
John Shaw Brown was an enthusiastic supporter of liberal politics, and backed the tenant right campaign of William Sharman Crawford (qv). In the 1880 general election he was unsuccessful when he stood as a liberal in Belfast, securing 5,122 votes but coming fourth of four candidates; in a hard-fought by-election in Co. Down (July 1885) he polled almost as many votes as Lord Arthur Hill, and he stood against one of the Warings in the 1885 election in Down North, but was again unsuccessful. He published a pamphlet on the liberals’ record of legislation for working men, and was a founding member of the Ulster Reform Club. In 1879 he set up a committee to send help to distressed areas in Connacht. His health failed, and he died in Ragatz, Switzerland, on 18 July 1887. He married (7 January 1847) Ellen Kertland (1820–1915); they had three sons and two daughters, all of whom survived him. One son, George Herbert Brown (1855–1908), became chairman of the company.
The eldest son, John Brown (1850–1911), scientist, was born 24 February 1850 in Donagh or Donard Lodge, Waringstown, Co. Down. After education in the RBAI and in Bonn, Germany, he entered the family firm. He became a partner, but retired from business in his thirties to concentrate on scientific research in his private laboratory. His first scientific paper, discussing the Voltaic theory of electrical contact, was published in the Philosophical Magazine in 1878, and was followed by others on Volta and on electrolysis. He designed and built some of his own apparatus, including an impressive Rühmkorff coil, and was respected as a careful and resourceful experimenter. He was elected FRS (5 June 1902) and was also a fellow of the Physical Society, an associate of the Institute of Electrical Engineers, and a member of the British Association; in 1902 he helped organise the important visit of the Association to Belfast, and with it visited South Africa (1905). Interested in the theory of education as well as in the promotion of science in Ireland, he was a governor of his old school, and was thrice president of the Belfast Natural History and Philosophical Society. In 1895 he bought a steam-powered car, and thus became perhaps the first motorist in Ireland; he later patented spring wheels, which he used in building a car powered by electricity. His interest in motoring led him to become president of the Irish Roads Improvement Association, and he developed a machine for recording a profile of a road surface, which he called a viagraph. He held other patents, including one for a camera tripod, and also worked on ideas for improved railways. Brown died 1 November 1911. His first wife, May (née Kertland), was probably a cousin. He later married Alice Davies of Lisburn; there were two sons (both of whom married Kertlands, who were probably their cousins) and a daughter.