Science fiction writer Damon Knight, via John Keel: "One sailent fact about UFOs is missing from all modern accounts I have seen. [Charles] Fort's data show that they are not isolated phenomena. Unknown flying objects, unknown bodies seen in space, appearances and disappearances, poltergeist activity, falls of strange substances and organisms from the sky – all these things show strong positive correlations with each other. Taken together, they show evidence of rhythmic fluctuation.” In other...