Correspondence and papers, including 10 laboratory notebooks, ca. 1879-1915; notes of lectures attended and given 1870-1906; correspondence and notes, 1868-1916 (16 vols.); manuscripts of his 'Elements and Electrons' (1912); and lists of his own published papers, 1872-1912. Bound volumes contain letters to Ramsay, with a few early letters from him. They relate to student days at Glasgow and T bingen Universities; Ramsay's short period at University College Bristol, 1881-1887; work on the rare gases at University College London (with Travers and R. Whytlaw-Gray) with copies of published papers by Ramsay and Travers, photographs of laboratories, apparatus, etc.; and work on radium with Frederick Soddy. The collection also includes Ramsay's laboratory notebooks, which give accounts of the discovery of argon and helium, neon, krypton and xenon, and of work with Soddy on radon. There are notes of lectures Ramsay attended when a student at Glasgow, and of lectures he gave when Professor at University College London. Correspondents include: Marcellin Berthelot, 1894-1899; Sir W. Crookes, 1894-1895; Emil Fischer, 1895-1914; R. Fittig, 1877-1902; G. F. Fitzgerald, 1884-1895; W. Huggins, 1895-1905; T. H. Huxley, 1887-1894; K. S. Olszewski, 1894-1895; W. Ostwald, 1887-1910; Lyon Playfair, 1885-1899; F. M. Raoult, 1891-1900; Sir G. G. Stokes, 1880-1893; J. H. van't Hoff, 1888-1910.