The collection contains a wide range of material relating to the development and work of the company. The papers include bound volumes of the company's catalogues and early price lists, 1882-1953; a large number of manufacturing drawings, with many assembly drawings, for the company's products, c. 1890-1970; a notebook of Horace Darwin, with entries for 1873-1890; two press-copy letter-books of Horace Darwin, c. 1877-1883, and four of the company's press-copy letter-books of the 1880s; one sales order book and two cash books of the 1880s; the 1895 articles of association and directors' agenda books of 1895-1906; early minute books of the Social Club and Benefit Fund; copies of the board minutes, accounts and other papers of the American associate company; a large collection of operating instructions and repair manuals for the company's instruments; comprehensive notes of important items in the Board Room minutes for 1895 to the 1960s compiled by A.F. Wolfe, c. 1962, the original minutes being lost; Paul Trust minutes, extracts, correspondence and administrative papers, 1952-1967; George Kent files, 1967-1971; papers relating to the company's Stereoscan, Geoscan and Microanalyser, c. 1961-1969; overseas files; press cuttings; test results; and many miscellaneous documents, including patents, memoranda and letters, c. 1890-1970. The collection also includes around 10,000 photographic negatives, with album prints, c. 1900-1970, of people, buildings and instruments.