7 June 1761 - 4 October 1821
Rennie was born near Edinburgh, the fourth son of a prosperous farmer. He played truant from school to observe the local millwright - Andrew Meikle, the inventor of the threshing machine and began working for him when he was 12 years old, whilst continuing his education. He matriculated from Edinburgh University.
He travelled south to increase his knowledge and whilst in Birmingham met James Watt who had previously been employed surveying canals. Watt offered him a job and Rennie worked 5 years for him manufacturing steam engines. He moved to London in 1791 and set up his own engineering business to expand into civil engineering, particularly the construction of canals. Among his first works were the Lancaster Canal (1792 - 1803), the Chelmer and Blackwater Canal (1793), the Kennet & Avon Canal (1794 - 1810) and the Royal Military Canal (1804-1909).
During this time Rennie acquired a deserved reputation as a builder of bridges, combining stone with new cast-iron techniques to create previously unheard-of low, wide, elliptical arches. These included the Lune Aqueduct (1793 - 1797), the Dundas Aqueduct on the Kennet and Avon canal (1800), Kelso Bridge (1800 - 1804), Waterloo Bridge (1811 - 1817), Southwark Bridge (1815 - 1819) and London Bridge (1824 - 1831) although he died before this bridge was completed. It is worth noting that his design for Waterloo Bridge was based on Harrison's Skerton Road Bridge in Lancaster (1783-88).
Rennie also worked on the development of docks and harbours for the Royal Navy - Chatham, Devonport, Plymouth, Portsmouth, Holyhead, Ramsgate and Sheerness - building the infrastructure for a century of world domination of the seas. Rennie was also commissioned to give advice on other novel maritime structures notably steam-powered dredgers, diving bells and the famous Bell Rock lighthouse.
On the Lancaster Canal he has left a legacy of many elegant structures notably the aqueducts over the Lune, Keer, Wyre and Brock. Of the bridges constructed on the canal the majority are listed buildings.
He was elected a Fellow of the Royal Society in 1798 and when he died on 4 October, 1821, aged 60, he was buried in St Paul's Cathedral.
Rennie's work on canals, aqueducts, bridges and dockyards mark him as one of the greatest engineers of his age.
Photographs of the Lune Aqueduct, John Rennie and the Wyre Aqueduct.