L. Frank Baum

“ Dorothy had meant to command the Belt to transform the magician into a Dove of Peace, but in her excitement she forgot to say more than "dove," and now Ugu was not a Dove of Peace by any means, but rather a spiteful Dove of War. His size made his sharp beak and claws very dangerous, but Dorothy was not afraid when he came darting toward her with his talons outstretched and his sword-like beak open. She knew the Magic Belt would protect its wearer from harm. ”

“ The magician instantly realized he was being enchanted, for he could feel his form changing. He struggled desperately against the enchantment, mumbling magic words and making magic passes with his hands. And in one way he succeeded in defeating Dorothy's purpose, for while his form soon changed to that of a gray dove, the dove was of an enormous size, bigger even than Ugu had been as a man, and this feat he had been able to accomplish before his powers of magic wholly deserted him. ”

“ The thick, tough skin of the big frog was not easily damaged, but Dorothy feared for her champion, and by again using the transformation power of the Magic Belt, she made the dove grow small until it was no larger than a canary bird.
Ugu had not lost his knowledge of magic when he lost his shape as a man, and he now realized it was hopeless to oppose the power of the Magic Belt and knew that his only hope of escape lay in instant action. ”