There is a school of thought that holds that the dramatic Orson Welles War of the Worlds scare, on the evening of October 30, 1938, provided the real basis of the science fiction magazine boom of that period. That the program may have helped give impetus to the spate of new publications is quite possible, but that it inspired them is impossible, since four new magazines … had been publicly announced as forthcoming before the date of the program.

Until wartime paper shortages curtailed publishers' optimism … [fifteen additional science-fiction magazines] would be added to the list. By contrast, before the boom there had been but four magazines in publication, and one of them was predominantly supernatural…. (p. 336)

The demands of this widening market naturally attracted to the field many authors who had never written science fiction, as well as lured back others who had been absent for a long period. Most...