The American. Harry Beckhoff was a marvelous illustrator, and this is among his best work. It conveys a sense of fun and adventure, seemingly channeling a Raiders of the Lost Ark that would not debut for another forty-three years. The English, on the other hand, gave us a photo of the author Evelyn Waugh who, though a gifted writer, was a notorious misanthrope.
A copy of the American edition is available here.