June 1936 issue ~ cover art by Blaine (Norman Saunders) June 1936 cover art by Blaine (Norman Saunders)
August 1934 issue ~ cover art by Lyman Anderson August 1934 cover art by Lyman Anderson better image than previously posted
May 1938 issue ~ cover art by Stockton Mulford May 1938 cover art by Stockton Mulford better image than previously posted
by a noted and influential Science Fiction Grand Master 1950 Beacon – first paperback reissue with different title 1952 Harlequin paperback reissue with the original title