“Timmy will be so thirsty,” said George. “He keeps licking round his mouth in the way he does when he wants a drink.”

“Well, I feel like licking round my mouth too,” said Dick.

They were half-asleep when the knife came thudding into the room. Timmy leapt up at once and barked madly. He stood and stared at the knife that lay gleaming in the moonlight, and barked without stopping.

“A knife!” said George, in amazement. “A knife with a string tied on the end!”

“It’s blunt,” said Julian, picking it up. “The tip has been filed off. What’s the meaning of it? And why the string tied to it?”

“Be careful that another knife doesn’t come through,” warned Terry-Kane.

“It won’t,” said Julian. “I think this is something to do with Jo. She hasn’t gone to the police. She has got the fair-folk to help us. This is Bufflo’s knife, I’m sure!”

They were all round him, examining it now. “I’m going to the window,” said Julian. “I’ll look right out into the courtyard. Hold my legs, Dick.”

He climbed up on the stone sill and crawled a little forward through the deep-set slit. He came to the outer edge of the window and looked down. Dick hung on to his legs, afraid that the sill might crumble away and Julian would fall.

“I can see four people down in the courtyard,” said Julian. “Oh, good — one is Alfredo, one is Bufflo — and I can’t make out the other two. AHOY down there!”

The four men below were standing looking up intently. They saw Julian’s head appear outside the window, and waved to him.

“Pull in the rope!” shouted Bufflo. He had now tied the end of a second peg-rope to the thin rope, and he and the others lifted it so that it might run easily up the wall.

Julian slid back into the tower room. He was excited. “This string on the knife runs down the wall and is tied to a thicker rope,” he said. “I’ll pull it up — and up will come a rope that we can climb down!”

He pulled on the string, and more and more of it appeared through the window. Then Julian felt a heavier weight and he guessed the thicker rope was coming up. Now he had to pull more slowly. Dick helped him.

Over the window-sill, in at the window, appeared the first length of the peg-rope. The children had never seen one like it before, they were used to the more ordinary rope-ladder. But Terry-Kane knew what it was.

“A peg-rope,” he said. “Circus people and fair-people make them — they are lighter and easier to manage than rope-ladders. We’ll have to fix the end to something really strong, so that it will hold our weight.”

Anne looked at the peg-rope in dismay. She didn’t at all like the idea of climbing down that, swinging on it all the way down the high stone wall of the tower! But the others looked at it with pleasure and excitement — a way of escape — a good, strong rope to climb down out of this hateful cold room!