Ex-library, properly de-accessioned, with all expected labels, paste downs, stamps and markings. Jacket under mylar with labels. Appears that one might have been removed, scuffing the spine at the author's name. Head, tail, corners bumped. Tape ghosts and foxing. Meets all points with E7 on the final printed page. The book was once considered rare--so rare the author did not own one. There are a few copies available signed, and several book clubs which were issued several times in 1963 as well as later on. The book remains in print as a shining example of the Golden Age of Science Fiction and the birth of space opera. According to Peter Nicholls this is a fix-up of "The Great Engine","The Wonderful Man" (under the title "The Changeling"), and "The Beast" originally published in ''Astounding Science Fiction'' 1943, 1944. According to Icshi: Chapters 1-5: "The Great Engine" 1943; Chapters 5-11: The Changeling 1944; Chapters 12-13: linking material; Chapters 14-31 Epilogue: "The Beast" 1943. Icshi writes: "each story has undergone substantial revision", but "The Changeling was thoroughly re-written."