It became a perennial best seller, spawning several sequels, and was animated by Disney as part of the feature anthology Melody Time. During World War II, he worked in Hollywood producing training films for the United States Army Air Forces.
It frequently appeared on bestseller lists, resulting in multiple sequels, and was animated by Disney as part of the feature anthology Melody Time. During World War II, he created instructional films for the United States Army Air Forces while employed in Hollywood.