Correspondence with the Secretary of the Astronomical Society of the Pacific, 1897-1914, concerning the award of the Bruce Gold Medal to Simon Newcomb, 1898; Arthur Auwers, 1899; David Gill, 1900; G.V. Schiaparelli, 1902; William Huggins, 1904; W.C. Vogel, 1906; E.C. Pickering, 1908; G.W. Hill, 1909; J.H. Poincaré, 1911; J.C. Kapteyn, 1913; and O. Backlund, 1914.
Correspondence and papers relating to the Optical Society, 1905-1910, including notices of meetings, lists of members and correspondence on a optical convention in 1905.
Correspondence with miscellaneous clubs and societies, 1903-1909:
1903: Faraday Society.
1904: Société Belge, Alliance Francais, Bureau des Longitudes and the British Science Guild.
1905: International Congress of Ideology.
1906: General Board of Opticians, South Eastern Union of Scientific Societies, Royal Photographic Society, Urania Society, Union Literary Society and the Royal Society of Edinburgh.
1907: Société Belge and Société Astronomique de France.
1908: Royal Cornwall Polytechnic Society and the Civil and Mechanical Engineers' Society.
1909: Optique Medicate, Optical Society, Leeds Health Congress and the Astronomical and Astrophysical Society of America.
Correspondence with societies, clubs and individuals, 1893-1901: the Imperial Academy of Science; Lewisham and Blackheath Scientific Association; Vanburgh Park Literary Society; Royal Society Club; Library Association; Society of Arts; W. Morley Martin; Toronto Astronomical Society; J.N. Reuter; Académie des Sciences, Paris; and the Société des Astronomiques de France.