“Fool’s Errand” was the second story del Rey wrote after moving to New York in 1944 where he rented a $3/week room near Ninth Avenue and Fifty-Seventh Street, but Campbell rejected the story for Astounding as being too obvious. It was another seven years before Roger Sidney would find his way into the pages of Science Fiction Quarterly, one of the new spate of 1950s sf magazines.
This was the first book that I got through the Scholastic Book Club when we moved to Bellevue in 1968. Each month, the club would give you a flier where you ticked off the books that you wanted, and the next month the books would magically show up at school!