Athanasius Kircher, a German Jesuit in 17th-century Rome, was an extraordinary polymath. His fascinating correspondence with popes, princes and priests was a key to the mind-set of the period, and the transition from medieval to modern scientific thinking.

John E. Fletcher, M.A. (1966), Queen Mary College, University of London. Senior Lecturer in Germanic Studies, University of Sydney. Before his early death in 1992 he had published extensively on Athanasius Kircher and his correspondents.