Rennie, JOHN, civil engineer, was born at the farm of Phantassie, near East Linton, East Lothian, 7th June 1761. After being for some time a workman in the employment of Andrew Meikle, inventor of a Thrashing-mill (q.v.), he attended the lectures of Robison and Black at Edinburgh University. He visited (1784) the works of Messrs Boulton and Watt at Soho, near Birmingham, and was immediately taken into employment by that eminent firm. Here his mechanical genius soon displayed itself; and so highly did Watt esteem Rennie that he gave him, in 1789, the sole direction of the construction and fitting-up of the machinery of the Albion Mills, London; and the ingenious improvements effected in the connecting wheel-work were so striking that Rennie at once rose into general notice, and abundance of mill-work now flowed in upon him. To this branch of engineering he added, about 1799, the construction of bridges, in which his pre-eminent talent and ingenuity displayed themselves. The chief of his bridges were those of Kelso (1803), Leeds, Musselburgh, Newton-Stewart, Boston, and New Galloway, with the Waterloo Bridge over the Thames, which was commenced in 1811, and finished in less than six years, at a cost of more than £1,050,000 (see Vol. II. pp. 437-8). Another of his works is Southwark Bridge; he also drew the plan for the London Bridge, which, however, was not commenced till after his death. He superintended the execution of the Grand Western Canal in Somerset, the Polbrook Canal in Cornwall, the canal between Arundel and Portsmouth, and, chief of all, the Kennet and Avon Canal between Newbury and Bath; he also drained a large tract of marsh land in the Lincoln Fens. (The Bell Rock lighthouse was almost wholly the work of Stevenson.) The London Docks, the East and West India Docks at Blackwall, the Hull Docks, the Prince's Dock at Liverpool, and those of Dublin, Greenock, and Leith were all designed by him, and wholly or partially executed under his superintendence. He also planned many improvements on harbours and on the dockyards of Portsmouth, Chatham, Sheerness, and Plymouth; executing at the last-mentioned port the most remarkable of all his naval works, the celebrated Breakwater (q.v.). He also made great improvements in the diving-bell. He died October 4, 1821, and was buried in St Paul's Cathedral. A striking characteristic of his works is the remarkable combination in them of beauty and durability; and though they were frequently objected to on the ground of costliness, yet in the end their lasting qualities more than compensate for this. In person Rennie was of extraordinary stature and herculean strength. See Smiles's Lives of the Engineers (1874).
GEORGE RENNIÉ, civil engineer, and eldest son of the preceding, was born in Surrey, January 3, 1791, educated at Edinburgh University, and commenced the practical study of engineering, under his father, in London in 1811. In 1818 he was appointed superintendent of the machinery of the Mint, and at the same time aided his father in the planning and designing of several of his later works. After his father's death in 1821 Rennie entered into partnership with his younger brother, John (afterwards Sir John Rennie), as engineers and machinery constructors; and during the existence of the firm it carried on an immense business, including the execution of most of the works which had been planned by the elder Rennie and the completion of those which he had left unfinished. Their operations embraced the construction of bridges, harbours, docks, shipyard and dredging machinery, steam-factories, both in Great Britain and on the Continent, and marine engines for warships. They built ships both of wood and iron, drained large tracts of land in the midland counties of England, and superintended the construction of several continental railways. George Rennie died 30th March 1866.
His brother, SIR JOHN RENNIÉ, associated with him in business till 1845, was born August 30, 1794, entered his father's office previous to the construction of Southwark and Waterloo bridges, and was knighted on the completion of London Bridge, which he executed from his father's designs. He acted as engineer to the Admiralty for ten years, and, in conjunction with his brother, contributed to the introduction of the screw-propeller into the navy. He had a wide reputation for all subjects connected with hydraulic engineering, harbour-works, &c., and a list of his important engineering works will be found in his Autobiography (1875). He died September 3, 1874. He was author of British and Foreign Harbours (1854) and a monograph on Plymouth breakwater (1848).