John Rennie, a British engineer, born at Phantassie, Haddingtonshire, June 7, 1761, died in London, Oct. 16, 1821. He learned the trade of a millwright, studied mathematics two years, settled in London in 1783, and engaged in the construction of steam engines and machinery. He planned and superintended the stone bridge at Kelso, below the junction of the Tweed and Teviot, the Waterloo and other bridges over the Thames at London, the Kennet and Avon canal from Bath to Newbury, the London docks, the East and West India docks at Blackwall, the Plymouth breakwater, and many other great works. - George, his son (1791-1866), also a distinguished engineer, published "Experiments on the Strength of Materials," "The Frictions of Solids," and "The Frictions of Fluids." Sir John (1794-1874), brother and partner of the preceding, knighted on the opening of the new London bridge in 1831, was the author of "The Theory, Formation, and Construction of British and Foreign Harbors" (2 vols. fol., 1854).