Folders of correspondence with Royal Astronomical Society, mainly re papers submitted by Blackett on behalf of members of his Rock Magnetism Group for publication in 'Geophysical Journal' The papers involved include those by JM Ade-Hall, RL Wilson, PJ Smith, AD Havard, M Lewis, VLS Bhimasakaram and others, on various rock analyses referred to in the working papers, and are accompanied by covering or supporting letters by Blackett giving his opinion about their value. Some similar letters forwarding or acknowledging papers by these colleagues also remain in the general correspondence folders, where Blackett left them. 1962-1965