The Patchwork Girl of Oz, by L. Frank Baum (1913)

This is from one of my favourite books: The Patchwork Girl of Oz, written by L. Frank Baum.

"All very true," answered the Shaggy Man, quietly; "but I know this gate,  having passed through it many times." "How?" they all eagerly inquired.

"I'll show you how," said he. He stood Ojo in the middle of the road and placed Scraps just behind him, with her padded hands on his shoulders. After the Patchwork Girl came the Woozy, who held a part of her skirt in his mouth. Then, last of all, was the Glass Cat, holding fast to the Woozy's tail with her glass jaws.

"Now," said the Shaggy Man, "you must all shut your eyes tight, and keep them shut until I tell you to open them."

"I can't," objected Scraps. "My eyes are buttons, and they won't shut."

So the Shaggy Man tied his red handkerchief over the Patchwork Girl's eyes and examined all the others to make sure they had their eyes fast shut and could see nothing.

"What's the game, anyhow--blind-man's-buff?" asked Scraps.

"Keep quiet!" commanded the Shaggy Man, sternly. "All ready? Then follow me."

He took Ojo's hand and led him forward over the road of yellow bricks, toward the gate. Holding fast to one another they all followed in a row, expecting every minute to bump against the iron bars. The Shaggy Man also had his eyes closed, but marched straight ahead, nevertheless, and after he had taken one hundred steps, by actual count, he stopped and said:

"Now you may open your eyes."

They did so, and to their astonishment found the wall and the gateway far behind them, while in front the former Blue Country of the Munchkins had given way to green fields, with pretty farm-houses scattered among them.

"That wall," explained the Shaggy Man, "is what is called an optical illusion. It is quite real while you have your eyes open, but if you are not looking at it the barrier doesn't exist at all. It's the same way with many other evils in life; they seem to exist, and yet it's all seeming and not true. You will notice that the wall--or what we thought was a wall--separates the Munchkin Country from the green country that surrounds the Emerald City, which lies exactly in the center of Oz."

They were delighted to know this, and proceeded with new courage. 

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