The journey now before the children inspired awe, fear and excitement in them.
From the balloon, the Cloud looked even larger and more ominous than ever, because for the first time, they could see how all- encompassing it was, stretching into the distant haze to right and left; now they could see how dark its seething depths actually were.
Below them the ordinary clouds had cleared a little, and they could look down upon a beautiful patchwork-quilt landscape of fields and hills and rivers. They watched the ground go by under them in silence, the wind blowing in their hair.
"I've just realised," said Graham after a few minutes.
"What?" said Colin.
"The wind is blowing in a different direction to the way we're going."
"It can't be."
"It is, Col. Look at the clouds."
Graham was right. Though the wind was from the South, they were travelling East.
"It's the Maggot-Cloud," said Gwen with a note of fear in her voice.
"What do you mean?" said Colin.
"Can't you see, Colin?" she said. "It's dragging us towards it. It knows who we are, it knows we have the Candle, and it's dragging us into it to destroy us."
"That's ridiculous," said Colin. "The Cloud can't do that."
"How do you know?"
"It's a black cloud, nothing more or less. It came out of the earth during an earthquake, that's all," said Colin. "It can't drag us anywhere."
"You mean you don't believe what the Queen said about Elz-raal-whatsizname?" said Graham.
"I don't know. I mean, I believe he existed all right, and I believe the Fathers disappeared into the earth - but I don't know about all the rest," said Colin.
"Don't you believe the Cloud was created by magic?" said Graham.
"I wouldn't bet on it," replied Colin. "Remember what Darach said about the stars being holes in heaven – we didn't believe that, did we?"
"No," said Graham.
"Suppose this cloud were some sort of poisonous gas escaping from the earth - like all the smoke when Surtsey was born - that would explain it, wouldn't it?"
"I suppose it would. But what about the horsemen?" Graham said. "You can't explain them away with science, can you?"
"They're strange, admittedly, but why shouldn't they be men? Maybe all this stuff about them being made of darkness is just superstitious nonsense."
"What about the one the sunlight killed in the field?" said Gwen. "Did it, Gwen? Why couldn't he just have hit his head when he fell?"
"And that 'magic' of Darach's in the tower looked like a shrapnel-box"
"But Col," said Graham, "if your theories are right, and the Cloud is made of poison gas – what are we doing trying to destroy it with a candle?"
"That's just it," he replied. "If Darach and the others are right, and the Cloud was made by magic – then we stand half a chance of surviving – perhaps even winning.
"But if they're wrong, and all this can be explained by science and common sense, then we're risking our lives without a chance of saving this world or ours!"
There was a long silence.
"We've got to try," said Gwen. "We've got to."
"Yes, yes," said Colin. "Let's not talk about it any more."
They didn't, but the damage was done. The seed of doubt was well and truly sown.
"Look what I've found," cried Graham jubilantly.
At the bottom of the basket was a bundle of bread and fruit. "Food!" they all yelled.
"We'd better not eat it all at once," said Gwen. "We don't know how long it'll be until we have another proper meal."
"Always the sensible one, my sister," said Colin with a mock grimace.
They all laughed.
It seemed ages since they had laughed together, and it was to be a long time until they laughed together again.
They drifted on towards the Cloud, and the sun began to go down. Now there were mountains below them, and beyond the sharp peaks, a desert.
"I hope we get beyond the mountains before night falls," said Graham. "I don't like the looks of those mountain-tops."
"We'll be all right," said Colin.
Almost before the words had left his lips the balloon suddenly fell a few feet. Gwen shrieked. They all felt as if they had left their stomachs behind them.
"What's happening?" said Gwen.
"The hot air in the balloon is cooling," said Graham. "We're going down."
The mountains loomed, grim and forbidding.
"We'll be smashed to pieces if we hit one of those," said Graham.
"Shut up!" shouted Colin. "And start chucking out those sand-bags."
As they threw the sandbags out of the basket the balloon stopped falling. But the sharp, misted mountaintops were very much closer.
"Never a dull moment," said Colin.
Graham whistled through his teeth. "That was close," he said.
"If we can only get over the mountains," said Colin, "we can make a landing in the desert safely enough."
The balloon had begun to descend again, more slowly than previously, but still too quickly for safety. They threw out some more sandbags but it did little good. Soon there were no more bags to throw out. Now they were so close to the mountaintops they could almost have reached out of the basket and touched them. Twice the bottom of the basket scraped the razor-sharp rocks, and on the second occasion the impact tore a hole in it.
The balloon was now sinking rapidly. Small, misty clouds flew past. The mountain crags seemed to reach for them with sharpened fingers, to pluck them from the sky and dash them to the ground.
Though they were descending, they were still moving at quite a speed between the peaks, hurried on by the air currents. A sheer rock face loomed immediately in front of them. There was nothing they could do that would prevent the balloon smashing into it. All they could do was cling to the basket, frozen with fear, as the slate-grey face came closer and closer.
Then, quite suddenly, an air current caught them and lifted the balloon up and over the mountain. It was as if a giant hand had appeared from out of the mist and carried them over the threatening rock face.
They all breathed a sigh of relief, and the sight that met their eyes on the other side of the mountain was the most welcome one of their journey. Before them, the mountains gave way to a wide and empty plain, over which brooded the face of the Maggot-Cloud on the horizon.
Out of the thermal, the balloon began to descend again, more rapidly than ever.
"Hold on," said Colin. "We're going to land with quite a wallop."
The sandy plain rushed up to the meet them, as the balloon plummeted like a dying bird. The wind whistled in their ears. They closed their eyes as they hit the ground, bounced and hit it again. The children were flung out of the basket on to the sandy ground, taking in great gulps of air, and feeling for broken limbs. But they were unharmed. They had landed, safely, on the other side of the mountains.