Papers of Professor William Cawthorne Unwin, 1856-1952, comprising correspondence, principally concerning engineering matters, 1856-1931, 1950,1952, notably with Edward Dean Adams, including the Niagra Falls Scheme, 1890-1929, Sir Benjamin Baker, including the Forth Bridge, dam schemes, 1882-1898, Sir William Fairbairn, including experiments, appointments, 1856-1874, Thomas Hardy, concerning astronomy, 1881, Imperial College, 1910-1926 (as representative of the Institution of Civil Engineers);
research papers, 1859-1924, notably Fay and Newall brakes, 1859, observations on the Thames, 1882-1883, Nile Project Committee, 1919, dam schemes, 1899-1905;
speeches and addresses to various institutions, including presidential addresses to the Institution of Civil Engineers, 1912, and Institution of Mechanical Engineers, 1916; engineering drawings, 1875-1906, of apparatus, machinery, sections of the Thames, Telok Ayer key wall, Singapore; two portraits of Unwin, undated;
additional material, comprising papers relating to Windsor Water Works arbitration, 1884; reports on compression gauges, 1886-1887; Birmingham dams, 1895; notes on dam theory, 1905; papers relating to Stockport water supply and Kinder Dam, 1905; notes relating to schemes for Niagra and central London.