It was in 1940's Horton Hatches the Egg that Dr. Seuss introduced the general public to Horton the Elephant, who would become one of his most famous characters. In Horton Hatches the Egg, the eponymous Horton is tricked into sitting on a bird's egg to keep it warm while the egg's mother takes what turns out to be a permanent vacation. But Horton, the kind elephant he is, persists and continues to stay on the egg.
When it was released, Horton Hatches the Egg was profoundly critically and financially successful. In a very positive review, for example, The New York Times Book Review wrote that Horton Hatches the Egg is "A moral is a new thing to find in a Dr. Seuss book, but it doesn't much interfere with the hilarity with which he juggles an elephant up a tree. To an adult, the tale seems a little forced compared to his first grand yarns, less inevitable in its nonsense, but neither young nor old are going to quibble with the fantastic comedy of his pictures." The book also sold 6,000 copies in its first year and continues to sell very well to this day.
