The sound of the hammer echoed over the island. "Do you think the enemy will hear?" asked Jill anxiously.

"Can't help it if they do," said Andy. "We can't hammer without noise! Pass me the biggest nails you've got, Tom."

They all worked steadily for the whole of the morning. And at last Andy heaved a sigh of relief.

"Well—I think that's patched up. She won't last long without being bailed out, because I can't patch her really properly—but the girls can easily bail out whilst you and I sail the boat, Tom."

"Is she ready?" asked the girls eagerly.

"As ready as I can make her," said Andy. "Now you girls must go and get all the rugs, and Tom and I will get the food from where we buried it under the sand, at the top of our own beach by the shack. Well pile in everything we can, push her out into the water arid sail off! Golly, I never thought we'd be able to do this!"

The four of them set off to fetch everything. They felt cheerful and excited. It might take them ages to get home—but at last they were going to leave these strange unknown islands safely, and take their secret with them!

The girls gathered up the rugs. The boys tied the tins and boxes together and staggered over the island with their heavy load, back to the boat again.

It was difficult climbing down the cliff so heavily-laden, but they managed it safely. The girls threw down the rugs on the deck, and the boys packed the food into the cabin. Now they could go!

"Wait a bit—we'll take the old sail with us," said Andy. "I could rig it again, and it would help us."

He set off to get the sail—and then he suddenly stopped and looked down on the beach. There, by his foot, lay something that greatly astonished him.

"What is it, Andy?" called Tom, seeing Andy's-puzzled face.

"Look at this," said Andy, picking up a dry. clean match, that had already been struck.

"What about it? It's only a match," said Tom.

"It's a match that hasn't very long been struck," said Andy. "And it is lying on sand that has been covered and uncovered by the tide since we've been working on the boat this morning. Well—has any of us struck a match and thrown it down? No—we haven't! Then who has?"

"Oh, Andy—surely you are mistaken," said Jill, looking ready to cry. "Nobody else has been here. We should have seen them."

"I'm wondering if anyone has been here whilst we were fetching the rugs and the food," said Andy, looking all round. "I don't like it—and, oh golly—look at that set of footprints in the sand over there! They are not our footprints!"

The four children gazed at the set of large footprints. Whoever made them had been wearing nailed boots—and the children all wore rubber shoes.

The girls were frightened. Yes—someone had been on the. beach whilst they had left it to get rugs and food. But Who? And where was he?

"Well—let's get the boat launched and hope to get away before we're stopped," said Andy. "Come on—we'll do without the sail."

They ran to the boat and took hold of the rope to drag it down to the sea—but even as they took hold of it, a loud voice shouted to them from round the corner of the cliff.

"Stop! Halt!"

The children stopped hauling the boat and stared round. They saw the enemy—four of them! One of them was the man who spoke English, and it was he who was shouting.

The children stared in fright at the four men, who came quickly over the beach. They spoke to one another in a foreign language. Then the first man spoke again.

"So! There are four of you—and all children! This is the boy who escaped—ah, you thought you were very clever, didn't you!"

"I did, rather," said Tom boldly. He felt frightened—but he wasn't going to show it! No—he was and these men shouldn't think they could sc

"You took your boat off the rocks, and thought you would escape safely, didn't you?" said the man mockingly. "Well, you made a mistake. We shall now take the boat away—and you shall remain prisoners on this island for as long as we want you to! Take out the food and the blankets again. You will need those if you live here for months!"

The children sulkily took out all the food and rugs they had so cheerfully put into the boat. Tom was glad to see that neither Jill nor Mary cried. Good! That would show the enemy how brave British children could be!

"Now we are going," said the man who spoke English. He gave a rapid order to the other men, who ran off round the cliff and then reappeared in a small boat, bobbing on the waves. It was plain that they had landed round the cliff, watched the children, and then come to catch them.

Andy and the others had to watch the men drag their ship down to the sea and launch it. They had tied their little rowing-boat behind it, and now waving mockingly to the children, they made their way over the water, round the cliff, and out of sight, rowing! Andy's boat along swiftly.

The children watched them go, anger and despair in their hearts All their work for nothing! How they had battled with the sea that morning—how they had slaved to get that boat right! And now they had all been discovered, their boat had been taken, and they were real prisoners.

Andy shook his fist at the disappearing ship, with the small boat bobbing behind it.

"You think you can beat a Scots boy, but you can't," he cried. "I'll beat you yet! You and your submarines!"

Wearily the children gathered up the old rugs and all the food and made their way up the cliff, across the island and back to their shack They packed the food on the floor in a corner and threw the rugs on the beds.

Then they sat on the beds and looked at one another. Not till then did the girls begin to cry But cry they did, letting the tears run down their cheeks without trying to wipe them off. They were so tired and so disappointed.

Tears came into Tom's eyes too, when he saw the two miserable girls. But he blinked them back, after one look at Andy's lean brown face Andy's blue eyes were like stones, and his mouth was stern and straight. Andy was not thinking of crying or grumbling. Andy was angry and fierce, and he sat in silence, looking straight before him, thinking hard.

"Andy—what are you thinking about?" asked Tom at last. "You look so stern. You're not angry with us, are you?"

"No," said Andy. "We all did our best—and we've got to do our best again, I tell you, Tom, we've got to leave this island! Somehow, we've got to get away and tell our secret. No matter what happens to any of us we must try to get home and tell all we have seen! As long as the enemy remain hidden in these islands, able to come here whenever they need food or fuel, then just so long will our ships be sunk round about these seas."

"Oh Andy—it's all very well to say things like that—but how con we get away now our boat's gone?" said Jill, wiping her eyes.

"I'll think of a way," said Andy. "Somehow, I'll think of a way. I'm going out by myself now, to puzzle a way out of this fix. Don't come with me. I want to be alone»

The boy slipped out of the shack. He climbed the cliff and sat in the heather by himself, his blue eyes fixed on the sky-line. How could he get home? How could he tell his secret? For two hours he sat there, puzzling and worried, so still that the gulls circled round his head and wondered if he were asleep.

And then Andy straightened himself and got up. He went down to the others, his eyes shining and his head up "I've thought of a way," he said proudly. "I've thought of a way at last!"