Correspondence regarding magnetism and meteorology, including correspondence with Messrs Jackson and Phillips, Madrid, Spain, 1946-1947, regarding the Kew unifiliar magnetometer and dip indicator, including an attached galvanometer, for a new geophysical observatory in Spain; a list of Royal Observatory instrument requirements, 1945; and correspondence regarding a silica coating for astronomical mirrors, 1947, including a communication from the Naval Scientific Service on 'The United States National Research Corporation Process for Producing Silica Films on Mirrors'. |