But as they came near, the door began to slide silently shut! Captain Arnold gave a shout and ran towards it.

“Hurry! They are shutting us out!”

He got there just as the door completely closed. There it rose above him, a tall, shining door, as wide as a great gate — fast shut.

“They’ve tricked us!” shouted the Captain angrily, and he hammered on the door. But there was no handle, no latch, nothing to get hold of or to loosen. There was no getting through that enormous door it was plain!

“The trap-door!” shouted Mike. “We can escape through that. The chief has left it open!”

The boys ran helter-skelter across the vast courtyard to where the opening was. They were half-afraid that the trap-door would close before they got there. But it didn’t.

The four boys stood by the lift-opening and looked down. The lift-shaft ran straight down below their feet, cut out of solid rock. The golden cage was not to be seen, of course. The opening looked dark and narrow as it disappeared into the darkness of the heart of the mountain.

“I don’t see how we could escape down there,” said Mike. “We would need a tremendous long rope to begin with — which we haven’t got — and also, just suppose the lift came up as we went down!”

“That golden cage was pulled up and down by ropes, wasn’t it?” said Mrs. Arnold. “Well, surely those must still be running down one side of the opening.”

“Of course they must,” said Captain Arnold. “We’ll look for those.”

But the ropes that sent the lift up and down had been cut! Captain Arnold found them easily enough, running in a cleverly cut groove at one side of the lift-opening. But when he pulled at them they came up in his hand, not more than ten feet long! Somehow they had been cut and were of no use at all!

“We may as well shut the trap-door,” said Captain Arnold, in disgust and disappointment. “It is dangerous to leave it open in case one of you goes and tumbles down the hole. Well — we really are in a fix now!”

“How all the Mountain Folk must be laughing at us!” said Mike. “We are nicely caught! Can’t get down, and can’t get up — here we are stuck on the top of a mountain for the rest of our lives!”

Captain Arnold did not like the look of things at all. He was afraid that the Folk of the Secret Mountain would open the sliding door and spring on them during the night. But he said this only to Mrs. Arnold, for he did not want to frighten the children.

“Well, we’ve all had a great deal of excitement today,” he said. “Let’s go into the cool temple, have a good meal, and a rest.”

So into the temple they went, and were soon munching away at the flat cakes and the sweet juicy fruit. Then the children and Mrs. Arnold settled themselves down for a rest whilst Captain Arnold kept watch. It was arranged that either the Captain, Jack or Mike should keep guard, so that at any rate the little party would not be taken unawares.

The night came as suddenly as usual. The stars flashed out brightly, and the world of mountains lay peacefully under the beautiful starlight. Captain Arnold went to examine the trap-door to make sure that no one could come upon them from there, and then he went to look at the sliding door. But it was still fast shut and there seemed to be no sound from the other side at all.

The night passed peacefully. First the Captain kept watch and then the two boys. But nothing happened. The dawn came, and the sun rose. The children awoke and stretched themselves. They were hungry — but, alas, except for a few of the flat cakes, there was no food left at all.

“I hope they are not going to starve us out,” said Mike hungrily, as Captain Arnold shared out the few cakes between the party. “I shouldn’t like that at all.”

“This adventure is exciting, but awfully uncomfortable,” said Nora.

At about ten o’clock the great golden door slid back again. Up the stairs came the Folk of the Mountain but this time they carried shining spears! They were on the warpath, that was plain!

Captain Arnold had half-expected this. He made the children go into a corner, and he went to meet the tall chief, with Mafumu close beside him to talk for him.

But the chief was in no mood for talking. He too carried a spear, and he looked very fiercely at Captain Arnold.

“Tell him I will kill his sun again, Mafumu,” said the Captain desperately.

“Chief say he kill you first,” said poor Mafumu, his teeth chattering. And, indeed, it certainly looked as if this was what the chief meant to do, for he lowered his spear and pointed it threateningly at Captain Arnold.

The Captain had a revolver. He did not want to shoot the chief, but thought he might as well frighten him. He drew his revolver and fired it into the air. The noise of the shot echoed round the mountains in a most terrifying manner. The chief jumped with fright. All the Mountain Folk began to jabber and shout.

But one, cleverer than the others, aimed his spear at Captain Arnold. The shining weapon flew through the air, struck the gun in the Captain’s hand, and sent it flying to ground with a clang. None of the Mountain Folk dared to pick it up, and Captain Arnold did not dare to either — for a different reason! He was not afraid of the revolver — but he was afraid of the spears around him!

The chief shouted out a harsh order, and twelve men ran up with spears. They took hold of all the little company, and before ten minutes had gone by, each grown-up and child was bound with thin, strong ropes!

“What will they do with us?” said Nora, who was very angry because her wrists had been bound too tightly.

Nobody knew. But it was plain that the little party were to be taken below into the heart of the mountain. They were not to be left on the summit.

“I expect the chief is afraid we will do something to his beloved sun if he leaves us up here,” said Jack. “I wish another eclipse would happen! What a shock it would give them all!”

The chief gave orders for the captives to be taken down the shining stairway — but just as they were about to go, there came a most extraordinary noise!

At first it was far away and quiet — a little humming — but soon it grew louder and louder, and the mountain-side echoed with the sound of throbbing.

“R-r-r-r-r-r-r!” went the noise. “R-r-r-r-r-r! R-r-r-r-r-r-r!”

The Folk of the Secret Mountain stopped and listened, their eyes wide with amazement. This was a strange noise. What could it be?

The children were puzzled at first too — but almost at once Jack knew what the noise was, and he lifted up his voice in a shout.

“It’s an aeroplane! An aeroplane! Can’t you hear it? It’s coming nearer!”

Captain Arnold was amazed. He knew that it was the noise made by the throbbing of aeroplane engines — but what aeroplane? Surely — surely — it could not be the White Swallow?

The noise came nearer — and then a black speck could be seen flying towards the mountain-side. It really was an aeroplane — no doubt about that at all!

The Mountain Folk saw it too. They cried out in surprise and pointed to it. “What are they saying, Mafumu?” shouted Jack.

“They say, ‘Big, big bird, big, big bird that sings r-r-r-r-r-r-r!’” said Mafumu, his eyes shining and his teeth flashing. The children laughed, excited and eager. Something was going to happen — they were sure of it!

The aeroplane came nearer and nearer, growing bigger as it came. “It is the White Swallow!” shouted Captain Arnold. “I’d know the sound of her engines anywhere, the beauty! Ranni and Pilescu must have somehow got back to the planes, made the White Swallow ready for taking off — and flown up in her.”

“Can they land here?” cried Paul.

“Of course!” said Mike. “Look at this great smooth courtyard — an ideal landing-ground if ever there was one! Oh, if only Ranni and Pilescu know this mountain when they see it, and they come here!”