"Something you think you see and don't see."
"I can't believe that," said Button-Bright. "If we only saw it, we might be mistaken, but if we can see it and hear it, too, it must be there."
"Where?" asked the Patchwork Girl.
"Somewhere near us," he insisted.
"We will have to go back, I suppose," said the Woozy, with a sigh.
So back they turned and headed for the walled city until it disappeared again, only to reappear at the right of them. They were constantly getting nearer to it, however, so they kept their faces turned toward it as it flitted here and there to all points of the compass. Presently the Lion, who was leading the procession, halted abruptly and cried out: "Ouch!"
"What's the matter?" asked Dorothy.
"Ouch—ouch!" repeated the Lion, and leaped backward so suddenly that Dorothy nearly tumbled from his back. At the same time Hank the Mule yelled "Ouch!" almost as loudly as the Lion had done, and he also pranced backward a few paces.
"It's the thistles," said Betsy. "They prick their legs."
Hearing this, all looked down, and sure enough the ground was thick with thistles, which covered the plain from the point where they stood way up to the walls of the mysterious city. No pathways through them could be seen at all; here the soft grass ended and the growth of thistles began.