The transitory mental aberration of Sidney Davidson, remarkable enough in itself, is still more remarkable if Wade’s explanation is to be credited. It sets one dreaming of the oddest possibilities of intercommunication in the future, of spending an intercalary five minutes on the other side of the world, or being watched in our most secret operations by unsuspected eyes. It happened that I was the immediate witness of Davidson’s seizure, and so it falls naturally to me to put the story upon paper.