Correspondence regarding various gravity surveys, including the Miller (Ottawa Observatory) Survey of gravity measurements at different national observatories, with the results, 1928-1929; the magnetic and gravity survey cruise off the Western Isles of Scotland, 1931; the United States Gravity Survey of the Bahamas, 1931; a report of the Committee for Geodesy and Geodynamics, 1930, concerning pendulum observations at various gravity stations in England; and a copy of a plan of the position of the National Gravity Station for Great Britain (at the Royal Observatory), scale 1:2500, 1929.