“All right,” said Andy. “But just keep a watch for any seaplane arriving. Lie down fiat under a bush or something if you hear one. You mustn’t be seen.”
“All right,” said Mary. “You can trust us to do that.”
So the next morning the four children once again climbed over the line of sKppery rocks at low tide. The boys had on only their bathing-suits. Andy had tied his oilskin packet safely to his shoulders, and in it was plenty of food for the day. The girls could get what they wanted from the cave.
All four went across the second island, over the heather and bracken to where they could see the third island. It lay in the sea before them, like a long blue and brown snake. Beyond they could see one or two more islands.
“Do you really think you can swan so far, Tom?” asked Mary doubtfully, as she looked at the wide spread of water between the second island and the third.
“Of course,” said Tom, who wasn’t going to give up this adventure for anything. All the same, the distance was further than he had ever swum before.
“Well—good-bye for the present,” said Andy to the girls. “We’ll get down to the shore here, wade out as far as we can, and then swim. Have you got Tom’? field-glasses, Jill? Good—you can watch us through them all the way to the third island!”
The boys went down to the shore, waded into the water, and then, when they were out of their depth, began to swim. Andy was by far the stronger swimmer—but he kept close to Tom, just in case the younger boy got into difficulties.
On and on they swam, using the breast-stroke because Andy said it was the least tiring. When Tom began to pant a little, halfway across, Andy spoke to him.
“Let’s do a spot of floating, Tom. That will rest us a little. It’s a long way.”
The two boys lay on their backs in the water. It was a little rough and choppy, but quite warm. They floated like logs of wood, spread out flat on the water. It was a fine rest for Tom.
Then once more they swam on—but it began to seem as if Tom would not reach the shore of the third island. His arms felt so tired. His legs seemed to have no push in them. He gasped and panted, and Andy began to feel alarmed.
“Tread water a bit,” he called to Tom. “Do you think you’ll be able to swim the rest of the way?”
“I don’t know,” said poor Tom, dreadfully ashamed of himself. But he could not seem to make his arms work properly. He was really tired out.
Andy was not in the least tired. He was as strong as a horse, and he trod water beside Tom, wondering what to do.
“Try again, Tom,” he said. “It’s no use going back! We are more than halfway across.”
Tom looked at the cliff of the third island. It seemed a long, long way away still. He tried again, striking out bravely with his tired arms. But after about six strokes he could not swim any more. He turned on his back and floated again.
Andy was really alarmed. ‘Tom, you can’t do any more,” he said. “I’D have to help you. I’ll swim on my baek and you must lie on your front and put your hands on my shoulders. I can drag you along in the water that way, but it will be rather slow.”
“Thanks, Andy,” said Tom, very angry with his poor swimming, but quite unable to do anything else. He took hold of Andy’s shoulders, and Andy, lying on his back with his head towards the third island, began to strike out valiantly with his brown legs.
It was very slow indeed. And now Andy began to get tired! Taking two people wasn’t nearly so easy as only one, and he began to gasp. Now wftat were they to do? If they both got into difficulties it would be a very serious matter.
It wasn’t long before neither Tom nor Andy had any strength left—and goodness knows what would have happened if Andy, striking out desperately with his legs, had not fdt something hard beneath him. It was a rock! He felt about with his feet and at last discovered a rock below the water. They had come to a kind of rocky reef rather like the one they had climbed over from their own island to the second one—but this line of rocks was not uncovered by the tide.
“Tom! Tom! Put your feet down and feel where the rocks are!” gasped Andy. “We can stand there—and maybe feel our way along a bit till we come to tne sandy bottom.”
Tom soon found foothold on the rocks under the vwater. He felt better at once. He and Andy held hands iSarf together made their way very cautiously over tins i sunken rocks, bruising their poor feet, but getting gradually nearer to the shore. And at last they felt the rocks stop, and there was sand beneath their feet! Good,
“Golly! I didn’t enjoy that very much,” said Tom. “Sorry I was so feeble, Andy.”
“It’s all right,” said Andy. “You did your best. We’re all right now.”
But in his own mind Andy didn’t think they were at all all right! How in the world was he going to get Tom over that stretch of water back to the second island gain? He would never, never do it! Andy was very worried indeed.
But he didn’t show it. He grinned at Tom, his blue eyes shining in his wet brown face. “We’re here at last!” he said. “And maybe we shall get a few surprises!”
They lay on the sandy shore in the sun for a while, drying themselves. Tom felt very much better alter a meal out of the oilskin packet. He almost felt as if he could swim back home again! It was wonderful what food did to Tom.
“I feel a new man now,” he said, leaping to his feet. “Come on, Andy, old chap. Let’s go up to the cliff-top and go across to the other side of this island, to see if we can spy anything.”
Andy got up too. The two boys climbed up the rough cliff and sat on the top to get back their breath. The island seemed to be about the same as the other two—covered with heather, bracken and grass, and with white gulls soaring over it.
They crossed the narrow width of the island and at last came to the cliff on the other side.
“Wriggle along on the ground now, just in case there’s anyone about,” said Andy. So both boys wriggled along on their fronts, and came at last to a lace where they could see down to the water far below.
And what they saw there filled them with such astonishment and alarm that for at least five minutes neither boy could say a word!
CHAPTER 11
The Secret of the Islands
THE sight that the two boys looked down upon was hardly to be believed. There was a very fine natural harbour of extremely deep water on the north-eastern ide of the third island—and lying in this water were at least seven or eight submarines!
Submarines! A submarine base in those deserted islands! No wonder so many of our ships had been sent to the bottom in the waters around these islands!
“It’s a real nest of submarines,” whispered Andy at last. “Enemy submarines I I can’t believe it. My word, Tom, we’ve stumbled on an amazing secret.”
The boys lay looking down on the water. Some of the submarines lay like great grey crocodiles, humped out of the water. One or two were moving out of the harbour, their periscopes showing. It was a curiously silent place, considering that so many of these underwater ships were there. There was no noise of shouting—no noise of machinery—just a dull throbbing every now and again.
“They get fuel and food here,” whispered Andy. They are the small submarines—this harbour can easily take a dozen or more. It’s a perfect place for submarines. Do you see how they haven’t built any jetties or piers—not a thing that anyone could see, if one of our own planes came over? All they would have to do then would be to sink under the water—and then there would be nothing to see. They store everything in the caves—golly, it’s amazing.”
For a very long time the two boys lay watching the Strange sight below. Two submarines slipped silently out of the harbour entrance—a way between two reefs of high rocks. A third submarine came in, and lay peacefully with the others, the men coming out on the deck and looking around.
At first Tom had been so full of surprise and alarm, go swept with excitement, that he could think of nothing but the sight of the queer vessels. Then another thought came into his head and he turned to Andy.