"Ay, ay, sir," returned M'Cracken, and dived with alacrity below. He was back in less than a minute. Then Tom entered the car of the airship, followed by Abdul and the stoker. With one hand on the steering wheel and the other on the lever controlling the engines, he called to the men to cast loose the ropes securing the car to the deck. Then he started the ascensional screw, and with a whirr like that of a gigantic humming-top the airship rose slowly from the yacht's deck.

"Good-bye, Tom," shouted Mr. Greatorex. "Be _careful_, my boy; run no risks."

"Good-bye! Good-bye!"

"This is ripping," said the stoker, as the machine rose higher and higher into the air.

Tom started so violently that he unconsciously jerked back the lever and stopped the motion of the machine.

"Pull that lever, quick!" he called.

"Done it already," said the stoker, with his hand on the lever that adjusted the planes. "Lucky I've been up before, Dorrell."

"Good heavens, you're-yes, you're Oliphant. Whew! won't the old man be in a tantrum. How in the world did you disguise yourself?"

"Sammy Byles' clothes, a little lampblack, and my native brogue do make a difference, don't they! I'm afraid Mr. Greatorex _will_ be a trifle fizzy; but that won't matter, afterwards."

"I'm not sure I oughtn't to go back and drop you."

"Nonsense. I'm in for it now, and when you come to think of it you couldn't have a better man. Bar Timothy, n.o.body knows so much about the machine as I do; and I warrant I'm a better hand in a scrimmage, whether with fists or revolvers. I've brought my Colt."

It was some time before Tom recovered from his surprise; but for the moment his attention was occupied by the airship. At last he said-

"Well, Oliphant, I'm glad enough to have you with me. I hope we shall come through all right."

While speaking, he had stopped the ascensional screws and set the horizontal going. A small aneroid hung just above his head, lit by a carefully screened electric lamp. The reading indicated that the airship had risen to a height of five hundred metres. Maintaining the ascent solely by the inclination of the planes, Tom brought the whole force of the engines to bear on the horizontal screws, and the machine glided onwards at a speed of some twenty miles an hour, gradually rising as she went. Then, at the alt.i.tude of a thousand metres, when Tom judged that he was high enough to clear the tops of the hills that fringed the coast, Oliphant reduced the angle of the planes so that it was just sufficient to maintain a constant height at the increased speed of twenty-five miles.

"By Jove, this _is_ ripping!" cried Oliphant again.

It was a bright starlit night, without a breath of wind. At this alt.i.tude the air was crisp and keen, producing a sense of exhilaration in the occupants of the car. Even Abdul, who had quaked inwardly and clutched the rail when the machine rose to such a giddy height, had now lost his tremors, and looked around him with wonderment and delight. The ship was soaring over the land, which lay outstretched like a vast black floor three-quarters of a mile beneath. Behind, the lights of the yacht could be faintly distinguished; before, there was not a glimmer over the whole country. The airship crossed a peak or two, then sailed over a rolling plain; by and by more hills loomed black in front. The aneroid, an extremely delicate instrument, now indicated that the machine was slowly sinking. Oliphant again adjusted the planes; the airship pa.s.sed clear of the hills, and Tom steered as directly as he could guess for the spot he had marked on his map.

When the voyage had lasted for about an hour the rising moon threw more light on the scene, lending a weird beauty to the variegated landscape-bare rugged hills alternating with wooded slopes and dark valleys. But it was impossible, at the height at which they were sailing, to distinguish any landmarks; Abdul knew the country thoroughly, but was quite at a loss in this unfamiliar situation. He had told Tom that the fastness where the diplomatist was probably held captive stood on the top of an extremely steep hill, and explained that the most convenient spot from which to approach it was a small tableland about a sixth of a day's journey from it. This was Tom's objective; but as it was impossible to make sure of reaching it unless Abdul could obtain some guidance from prominent natural features, Tom more than once allowed the airship to sink almost to the ground, so that the Moor might scan the country.

On one of these occasions, about four hours after they had left the yacht, Abdul said that he recognized a hill stream whose source was within a short distance of the sheikh's stronghold. From the directions he was now able to give, Tom managed to steer fairly straight for the tableland, and after once more descending so that Abdul might a.s.sure himself that he had not been mistaken, he finally brought the airship to rest at the desired spot. It was past three o'clock in the morning; the sky was already lightening with what Abdul called subhi kazib-the false dawn which often in these lat.i.tudes illumines the sky an hour or so before the real dawn. The three adventurers were all very tired, and on Abdul explaining that the tableland was but rarely visited, and that so far as he knew there were no wild beasts in the neighbourhood, Tom thought that they might all safely take a few hours' sleep before considering the next move. The tableland was not entirely flat; it had many depressions, and jagged rocks stood up on all sides around the comparatively clear s.p.a.ce on which the airship rested. Only one hill, and that apparently four or five miles distant, stood higher, and even the hawk-like vision of the mountaineers was not likely to discover the airship from so remote a spot.

The real dawn-subhi sadik-was some little while past when the Moor awoke, first of the three. He had just completed his morning devotions and ablutions at a little spring when the others roused themselves.

Among the contents of the car were a spirit lamp, a tin of condensed milk, and materials for making tea; and while they ate their breakfast Tom discussed with Oliphant the programme for the day.

"The first thing is to find out exactly where Ingleton is imprisoned,"

said Tom, "and what chance there is of getting into communication with him. That's a job for Abdul; obviously we can't help him; we can't do better than lie snug here while he goes and gets what information he can."

"A pretty dangerous job for him if he's caught, isn't it?"

"Well, it's a good many years since he left these parts, and he must have altered. I doubt whether he'll be recognized. Luckily the hills are covered with mist, too; if he starts soon he'll be able to get a good way before he's likely to run across any of his countrymen."

"Or lose himself?"

"No, master," said Abdul, "I don't not lose myself. I go all right."

"The sooner the better, then," said Tom. "We'll wait for you here."

The Moor, who had resumed his native dress, at once girt his djellab about him and prepared to descend the hillside. Tom and Oliphant watched him breathlessly until the mist hid him from view. He went over the brow of the hill and began to clamber down its steep side with the agility and sure-footedness of a mountain goat. When he was out of sight the others returned to their half-finished breakfast, ready to endure with what patience they might the long waiting until the Moor should have completed his errand.

"What if he doesn't come back?" said Oliphant.

"We shall have to risk it ourselves. I'm certainly not going back without making the attempt now that we have come so far. It's pretty cold up here; I shall be glad when the sun sucks up this mist."

When the mist at last cleared away, a magnificent view spread out before the two watchers on the hill-top. They themselves were perched on the top of a practically bare rock, but a hundred feet below them the hill side was covered with forest, broken, however, with huge patches of rocky ground, on which apparently not even the hardiest tree could find a lodgment. For miles around, the country showed a succession of tree-clad hills, with here and there a waterfall, and here and there a bare summit, not, however, truncated like the hill on which they had landed. Far away to the north-west they could descry, through their field-gla.s.ses, a considerable walled village perched on the shoulder of a hill, with one or two large buildings, one presumably a mosque, and a second evidently the stronghold of the sheikh. This no doubt was the place in which they were interested. It lay in the direction generally indicated by the Moor, although when he started it was hidden by the mists.

The hours dragged all too slowly by. They talked over the situation, occasionally getting up to stretch their limbs, but not venturing to move about much, lest they should be seen by any chance shepherd or hunter. On the plain below they caught sight of animals moving, and longed to take a shot at them-now a gazelle, now a wild hog. But to fire a shot was out of the question, and they had to content themselves with exchanging reminiscences of sport at home.

Darkness fell again. Abdul had not returned. Each spent a restless night, and rose with the dawn, eagerly scanning the country, as soon as the mist was dispersed, for a sign of their emissary, but in vain.

"I hope he hasn't been collared," said Tom.

"Or turned traitor!"

"He wouldn't do that, I'm sure. I like the fellow. Of course you read a lot about oriental duplicity, but I don't believe Abdul is a rogue.

Anyway, we should have time to get away in the airship before any one could molest us here, and he knows that. For the life of me I don't know what we can do if he _has_ been collared. We can't do a thing until we know where Ingleton is; we certainly can't go inquiring ourselves. All we can do is to go back to the yacht and try and pick up some English-speaking native who can tell us what we want to know, and that means loss of time."

"And more than that; it would mean that I'd have to turn into M'Cracken again, and I don't believe I could keep up the disguise any longer. I say, what's that moving down there?"

They seized their field-gla.s.ses and turned them towards a patch moving along the outskirts of a wood some miles away.

"Moors, by Jove!" exclaimed Oliphant. "And mounted. And coming this way.

It looks as though Abdul had betrayed us, after all."

"Don't be in a hurry. They're making no attempt to mask their approach.

I don't believe they're coming here at all. No; see, they are wheeling off to the right, in the direction of the hill village yonder. We needn't worry ourselves. But I'm getting sick of this, and it'll be serious soon. I only brought three days' grub in the car, and I'm afraid we ate more than we ought yesterday. That's the worst of having nothing to do."

"It's so plaguy hot, too, when the sun's up. For two pins I'd go down and have a shot at something in the woods. No doubt it's cooler down there, and there's no fun in lying about up here to frizzle."

"There'd certainly be no fun in being pitched into a Moorish dungeon. By all accounts they're rather horrible. I think I'd rather frizzle here than stew there. In any case, even supposing the Moors didn't find out who was firing, the shots would put them on their guard and perhaps spoil our game. I say, Oliphant, reel off some of your stories."

But even Oliphant's stories in the Doric palled, and by and by Tom got up and said that he was going for a stroll. He was away for nearly an hour, and Oliphant began to feel uneasy at his prolonged absence.

Oliphant dared not call, for fear of being overheard by an enemy; nor did he care to explore. But he was making up his mind to follow Tom down the steep path when the wanderer at last returned.

"Rather interesting spot, this," he said. "Round the corner below there I came upon some caves."

"I wondered what had become of you. Did you get lost?"

"No. The odd thing is that these caves are up about twenty feet from a ridge of rock, and can't be got at without a ladder. I tried to mount, but the wall is almost flat."

"I'll go and have a look. How do you get there?"

"Down the hill a little way, turn to the right, go along the ridge, and look up. The caves are about halfway between the ridge and the top of the hill."

Oliphant followed these directions, and by and by returned, with his trousers cut in several places.