George Rennie (engineer)

George Rennie (3 December 1791 – 30 March 1866) was an engineer born in London, England. He was the son of the Scottish engineer John Rennie and the brother of Sir John Rennie.

Born in the parish of Christchurch, Blackfriars Road, Southwark, London, on 3 December 1791, he was educated by Dr. Greenlaw at Isleworth, and was subsequently sent to St. Paul's School and to the University of Edinburgh. In 1811 he entered his father's office, where many great works were in progress. In 1818, on the recommendation of Sir Joseph Banks and James Watt, he was appointed inspector of machinery and clerk of the irons (i.e. dies) at the Royal Mint, which post he held for nearly eight years.

On the death of his father in 1821 he entered into partnership with his younger brother John, as J. and G. Rennie, and for many years they were engaged in completing the vast undertakings originated by the elder Rennie. John concentrated on the civil engineering portion of the business, whereas George supervised the mechanical engineering. Nevertheless, about 1826 he was entrusted with the construction of the Grosvenor Bridge (Chester) over the Dee at Chester, from the designs of Harrison.

In 1830, they were involved in the construction of George Stephenson's Liverpool and Manchester Railway. He had considerable practice as a railway engineer, and made plans for lines to connect Birmingham and Liverpool, the Vale of Clwyd line, the railway from Mons to Manage, and the Namur and Liege railway, of which he was appointed chief engineer in 1846.

Screw-propeller invented by George Rennie imitating the form of a tail fin

George Rennie's genius was chiefly mechanical, and he superintended the manufacturing business of the firm in Holland Street, where a great variety of machinery was turned out, including the first biscuit-making machinery, corn and chocolate mills for Deptford victualling yard, and the machinery at the Royal William Victualling Yard, Plymouth. They also constructed some locomotives for the London and Croydon Railway. Many orders for foreign governments were executed, and the firm were employed by the Admiralty in making engines for the Royal Navy. He was much interested in the screw-propeller, and his firm built the engines for Archimedes, the world's first propeller-driven steamship. Subsequently, in 1840, the firm built for the Admiralty the Dwarf, the first vessel in the British navy propelled by a screw.

Roe (1916) discusses Rennie's contributions to the development of the planer.

In 1822 he was elected Fellow of the Royal Society, and contributed papers to the Transactions in 1829 on the friction of metals and other substances. He also presented papers to the British Association and to the Institution of Civil Engineers, of which body he was elected a member in 1841.

He died on 30 March 1866, at his house, 39 Wilton Crescent, from the effects of an accident in the street in the previous year, and was buried on 6 April at Holmwood, near Dorking. He married, in 1828, Margaret Anne, daughter of Sir John Jackson, 1st Baronet, M.P., who survived him; they had two sons and one daughter.