The men entered their rubber boat and rowed back to the seaplane. Twice more they went to the cave and back. Then they climbed up into the plane and disappeared.
"I'm getting most awfully hungry," said Tom at last. "Can't we go and get something to eat?"
"I'll stay here and keep watch, and you and the girls can go and get your dinner," said Andy. "Don't light a fire, whatever you do—the enemy will see the smoke. Use the stove if you want to cook anything. Bring me something to eat and drink later."
"Right," said Tom, and he and the girls wriggled off the high ledge. They stood upright as soon as they were out of sight of the seaplane and tore to their shack.
They ate a hurried meal, and did not cook anything at all. They made up a dinner-packet for Andy and set off to take it to him.
But half-way there they heard a noise. R-r-r-r-r-r-r-r-r! R-r-r-r-r-r-r-r! R-r-r-r-r-r-r! They stopped at once and listened.
"It's the seaplane going off!" cried Tom—and then the sound came again, more loudly than ever. R-R-R-R-R-R-R.
"Look—it's there!" cried Jill. "Drop flat to the ground or we'll be seen!"
Jill had seen the seaplane just rising into the air over the cliff. The three children dropped flat to the ground and lay there perfectly still. The seaplane roared over their island, rose higher and higher, and at last was nothing but a speck in the sky.
"What a narrow escape!" said Tom, sitting up and wiping his forehead. "Golly! My heart did go bump I I've split the water I was carrying for Andy. I'll have to get some more!"
"It was a shock to see that enormous plane coming!" said Jill. "Oh dear—if we have many more shocks, my hair will turn grey!"
Chapter 10
And Now for the Third Island!
The children were very glad that the seaplane had gone. "It's a jolly good thing our signal was taken down before it flew over the island," said Andy, eating the food that the others had brought to him. "I couldn't warn you. It started up its engine all of a sudden, taxied over the smooth water there, and then rose into the air."
"Andy, do you think there's anything to be seen over on the other islands?" asked Tom.
"There may be," said Andy, "I think we ought to try and find out. That third island looks a peculiar shape to me—very long indeed, but very narrow. On the other side of it might be a fine natural harbour for seaplanes. There may be heaps there."
"Well, we've only heard one so far," said Tom. "It doesn't seem as if they're very busy, if there are lots over there."
"No—you're right, Tom," said Andy. "Well, what about going to see what we can find? I don't quite know how we'll get to the third island—have to swim. I think. I don't believe the girls could swim so far, though."
"I don't think I could," said Jill, remembering the long stretch of sea between the second and third islands. "You boys would have to go without us. Mary and I will stay behind and be as patient as we can."
"Shall we go to-morrow?" asked Tom eagerly. "We could cross to the second island at low tide in the morning and swim across to the third island. We could carry a little food with us, wrapped up in your oilskin."
"Yes—we'lldo mat," said Andy. A great feeling of excitement came over the children—a feeling as if some big unknown secret was going to be theirs. Jill shivered a little—it was almost too exciting.
"There's one thing I'm worried about" said Andy. "Just suppose we are discovered, by any chance—we must find some hiding-place."
"Well, there simply isn't any on this island," said Tom. "So we must hope we won't be discovered."
Nothing more happened that day. No seaplane came to the calm harbour in the waters of the second island. No sound but the sea-gulls came through the air. It was a lovely day and the children enjoyed themselves bathing and sunning their brown bodies.
Thanks to the store of food they had discovered on the second island they had plenty to eat. Andy caught some nice little fish, and Jill fried them in tine tinned butter. They were delicious. Now that they had tinned mule-powder they could make a milk-mixture and use it with their tea or cocoa, and could also sweeten their drinks with the sugar they had brought.
"We are really very well off now!" said Tom, who as usual was thoroughly enjoying his meal. "we'll take another exciting lot of tins away from the Round Cave next time—I saw some baked beans in tomato sauce. I should like those."
The children took turns at keeping watch on the second island from the rocky ledge. But nothing was to be seen at all. They went to bed early because the boys would have rather a hard and long day the next day.
"We shall have to clamber over that line of rocks first," said Andy. "And then we must cross the island and swim to the third one. We shall have to be back on the second island in time to clamber over the rocks at the next low tide. You girls mustn't worry about us. We shall be back all right."
"I do wish we were going too," said Jill. "Don't you think Mary and I could climb over the rocks to the second island and wait for you there? It would be more fun for us to play about there than on this bare island. There are lots of bilberries there we could pick—they are lovely and sweet now."
"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 slippery 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, half-way 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.