He had taken up with him a big stone. As everyone watched he smashed the glass round the tower with the stone. Crash! Crash! Crash!

The wires that ran through the glass were broken and split as the glass crashed into pieces. No power could race through them now. Uncle Quentin leaned out of the broken glass room and shouted exultantly.

“It’s all right! I was in time! I’ve destroyed the power that might have blown up the island — you’re safe!”

George found that her knees were suddenly shaking. She had to sit down on the floor. Timmy came and licked her face wonderingly. Then he too sat down.

“What’s he doing, smashing the tower up?” asked a burly fisherman. “I don’t understand all this.”

Uncle Quentin came down the tower and rejoined them. “Another ten minutes and I should have been too late,” he said. “Thank goodness, Anne, you all arrived when you did.”

“I ran all the way home, told Aunt Fanny, and we got the fishermen to come over as soon as they could get out their boats,” explained Anne. “We couldn’t think of any other way of rescuing you. Where are the wicked men?”

“Trying to escape down the under-sea tunnel,” said Julian. “Oh — you don’t know about that, Anne!” And he told her, while the fishermen listened open-mouthed.

“Look here,” said Uncle Quentin, when he had finished. “As the boats are here, the men might as well take all my gear back with them. I’ve finished my job here. I shan’t want the island any more.”

“Oh! Then we can have it!” said George, delighted. “And there’s plenty of the holidays left. We’ll help to bring up what you want, Father.”

“We ought to get back as quickly as we can, so as to catch those fellows at the other end of the tunnel, sir,” said one of the fishermen.

“Yes. We ought,” said Aunt Fanny.

“Gracious! They’ll find Mr Curton there with a broken leg,” said Anne, suddenly remembering.

The others looked at her in surprise. This was the first they had heard of Mr Curton being in the quarry. Anne explained.

“And I told him he was a very wicked man,” she ended triumphantly.

“Quite right,” said Uncle Quentin, with a laugh. “Well, perhaps we’d better get my gear another time.”

“Oh, two of us can see to that for you now,” said the burly fisherman. “Miss George here, she’s got her boat in the cove, and you’ve got yours, sir. The others can go back with you, if you like — and Tom and me, we’ll fix up your things and bring them across to the mainland later on. Save us coming over again, sir.”

“Right,” said Uncle Quentin, pleased. “You do that then. It’s down in the caves through that tunnel behind the stone.”

They all went down to the cove. It was a beautiful day and the sea was very calm, except just round the island where the waters were always rough. Soon the boats were being sailed or rowed to the mainland.