London, Scion, 1951. First Edition. First Impression. Paperback. A very good copy. Sole edition as far as we can tell, and perhaps Harkon's second of three books (the other two published as Astron Del Martia - both names pseudonyms for an unidentified writer). Harkon also wrote a couple of short stories. Spine a little rubbed and tips worn, a little toning internally and some light foxing, foreedge scraped. Cover art by Ron Turner [8806, Hyraxia Books].