The Cross-Correspondences were messages purportedly sent to mediums from Frederic W.H. Myers after his death via automatic writing. The interesting thing is that the mediums knew nothing of each other and the messages made no sense on their own. It was only when they were brought together that they did. Furthermore, the messages were made such that only scholars well versed in literature and classics knew their meaning; the mediums had no prior knowledge of this.
See also: F.W.H. Myers and the SPR - [Only admins are allowed to see this link]
See also: F.W.H. Myers and the SPR - [Only admins are allowed to see this link]