Notes:
Art submitted on December 9, 1948. Danish inventor Karl Kroyer once salvaged a shipwreck in Kuwait in 1964 in record time by pumping expandable polystyrene foam balls into its hull. When he went to register his process, he was denied a patent because the process had already been described in this comic. Strange but true! "Accounts of this incident appeared in 'Popular Science' for April 1965 and 'Chemistry' for September 1966, both of which evidently obtained their information (which differs in some details) from Danish publications. A few panels are reproduced with each article. (The dialogue in the 'Popular Science' article is not by Barks, it evidently was translated from the Danish.)" Second note and synopsis from "Carl Barks and the Art of the Comic Book" (M. Lilien, 1982).