James Beaumont Neilson was an engineer who contributed greatly towards the expansion of the British iron industry in the 19th century. He was born on the 22nd of June 1792 in Shettleston, Scotland, to Walter Neilson and his wife Barbara. Walter was an engine-wright at Govan colliery, and Neilson joined him there after leaving elementary education at fourteen. Neilson’s brother John would become a prominent engineer, and after two years at Govan Neilson became his apprentice at Oakbank. During his spare time, he studied physics and chemistry from Anderson’s Institution in Glasgow.
In 1814, Neilson was appointed as an engine-wright at a colliery in Irvine, but it was not to last; he lost his job when his employer’s business failed. Neilson then moved to Glasgow, and became appointed foreman at the Glasgow gasworks at the age of twenty-five. He rose through the ranks to manager and engineer, and used his influence to improve both the manufacture and utilization of gas and the lives of his employees. Neilson encouraged the men to educate themselves, establishing a workers’ institute which featured a library, lecture room, a laboratory, and a workshop.
Neilson is best known for his discovery of the value of hot blast in iron manufacture, a breakthrough which he began to research in the 1820’s. He came to the conclusion that the manufacture of iron would be more efficient if hot blast was used rather than cold. The prevailing view at the time was that cold blast was more effective for the manufacture of iron, and the ironmasters were reluctant to allow Neilson to test his theory on their furnaces. However, when the hot blast was finally tested at the Clyde ironworks, it was so immediately successful that two other men—Charles Macintosh and John Wilson—entered into a partnership with Neilson to patent the invention.
With refinement, hot blast allowed the same amount of fuel to produce three times as much iron, and with a wider range of fuel than had worked with cold blast. Neilson’s success—to the tune of £30,000 a year—led to controversy. In 1832 the Baird ironmasters challenged Neilson’s patent and refused to pay the licence duty that allowed them to use his process. The resistance snowballed; in 1833 Neilson had conducted three legal cases against iron companies who challenged his patent. He enjoyed several more years of success until 1839, when the Bairds challenged him again. This began a four year legal battle involving twenty separate court actions against different British iron companies, with many in Scotland forming an association against Neilson. The case was finally closed in England at the end of 1841, in Neilson’s favour. The Scottish trial in 1843 set a record for the longest trial conducted at the time and called over 102 witnesses before settling, again, in Neilson’s favour.
Neilson married Barbara Montgomerie in 1815. After her death, he remarried Jane Gemmell in 1846, but she would also died in 1863. In 1832 Neilson became a member of the Institution of Civil Engineers in London, and a fellow of the Royal Society in 1846. He retired in 1847, and purchased a property in the Isle of Bute, before moving to Queenshill in 1851. There, he founded an institution similar to the one he had set up for his workers in Glasgow. Neilson died on the 18th of January 1865, survived by four sons and three daughters.