Correspondents include: Coventry, D. Marshall, Mme Riches, E.H. Pamphilon (General Manager, Stephen Austin Printing House) and A. Olver (Research Secretary, Royal Institute of International Affairs). Also includes later correspondence about use by other authors of Worthington's illustrations and passages from the book. There is also correspondence with B.K. Temperley, Chief Hydraulic Engineer, Nairobi, about groundwater dating.