Experimental notes, working papers, correspondence and lecture summaries compiled by Charles Wheatstone, 1836-1875, and photographs collected by him in that period. Notably including papers relating to the development and testing of the telegraph, [1836-1960]; descriptions of experiments and test results concerning the measurement of electromotive forces and electrical potential, [1840-1875]; experimental observations on the nature of magnetism, electricity and thermodynamics, including electromagnet design, batteries and dynamos, [1834-1855]; working papers relating to optics including experiments into refraction, colouration of compounds and polarisation, [1850-1875]; drafts of lectures on sound and musical instruments prepared by Wheatstone, [1832-1837]; material relating to the management of the Wheatstone collection of scientific instruments and library, 1890-1992; biographical material relating to the life of Wheatstone, the invention of the telegraph and Wheatstone's musical instrument manufacturing business, with unrelated newspapers, 1757-1975; stereoscopic photographs and glass negatives taken by Roger Fenton, Samuel Buckle, Jules Duboscq and others, featuring landscapes, still lifes, panoramic scenes of cities including Paris and Moscow and the interior and exterior of the Crystal Palace, Hyde Park, Sydenham, 1851, and especially the Exposition Universelle, Paris, 1855, [1850-1901]; artefacts from Department of Physics, King's College London, including demonstration equipment, telegraph apparatus, a nail fiddle and other prototype musical instruments, [1834-1875]; exhibition of scientific and musical instruments, [1834-1875].

Papers created or collected by Edmonds during the course of his life and career, dated 1827-1838, 1852, 1879-1881, 1890-1957, principally comprising typescript memoirs covering his life and career, 1861-1951, and notably concerning his work at the Royal Military Academy, 1890-1896, and in the Intelligence Division of the War Office, 1899-1901, 1904-1908, his service in South Africa, 1901-1902, and in World War One, 1914-1918, at the Geneva Conference, 1906, as General Staff Officer, 4 Div, 1911-1914, and in the Historical Section of the Committee of Imperial Defence, 1919-1949, written in [1951]; correspondence with Rt Hon Sir Winston (Leonard Spencer) Churchill, 1922-1954, relating to Churchill's book The World Crisis, 1911-1918 (Thornton Butterworth, London,1923-1929, abridged and revised, 1931); letters from FM Douglas Haig, 1st Earl Haig and his wife, 1903-1939, mainly relating to Edmonds' work on the official history of World War One; correspondence with Maj Gen Sir Ernest (Dunlop) Swinton, 1919-1950; texts of lectures,[1908-1947], notably relating to the American Civil War, 1861-1865, laws of war and the organisation of intelligence and information in warfare; typescript and printed articles, 1893-1957, mainly relating to World War One; official army handbooks and reports by Edmonds and others, 1899-1918, 1945; papers related to World War One collected by Edmonds, dated 1900, 1907, 1914-[1945]; presscuttings, [1906-1943], mainly concerning political and military developments and international relations; photographs, 1895-1918, mainly of Edmonds with Army colleagues.