New York: Grosset & Dunlap Publishers, [1940s?];1933. Later printing. Octavo in tan cloth; dust jacket; 218 pp: illustration; 20 cm. Very Good(+) in Good dust jacket; mild toning to pages and textblock; no markings or tears to interior, binding tight; dust jacket shows shelf wear to edges, light chipping to top and tail of spine; pictorials bright. Hardcover.
"A plot to steal a top-secret instrument vital to the United States space program poses a challenging case for Frank and Joe Hardy. The whereabouts of their famous detective father is a mystery, so Frank and Joe are on their own to foil the plotter." --Publisher
