The Lord of the Rings, pages 687-688:
"Ware! Ware!" cried Damrod to his companion. "May the Valar turn him aside! Mumak! Mumak!"
To his astonishment, and terror, and lasting delight, Sam saw a vast shape crash out of the trees and come careering down the slope. Big as a house, much bigger than a house, it looked to him, a grey-clad moving hill. Fear and wonder, maybe enlarged him in the hobbits eyes. But the Mumak of Harad was indeed a beast of vast bulk, and the like of him does not walk now in Middle-earth: his kin that live still now in latter days are but memories of his girth and majesty. On he came, straight towards the watchers, and then swerved aside in the nick of time, passing only a few yards away, rocking the ground beneath their feet: his great legs like trees, enormous sail-like ears spread out, long snout upraised like a huge serpent about to strike, his small red eyes raging. His upturned hornlike tusks were bound with bands of gold and dripped with blood. His trappings of scarlet and gold flapped about him in wild tatters. The ruins of what seemed a very war-tower lay upon his back, smashed in his furious passage through the woods; and high upon his neck still desperately clung a tiny figure - the body of a mighty warrior, a giant among the Swertings.