After the publication of "The Wonderful Wizard of OZ" I began to receive letters from children, telling me of their pleasure in reading the story and asking me to "write something more" about the Scarecrow and the Tin Woodman. At first I considered these little letters, frank and earnest though they were, in the light of pretty compliments; but the letters continued to come during succeeding months, and even years.

Finally I promised one little girl, who made a long journey to see me and pref...