At this moment he observed a score of hors.e.m.e.n emerging at a rapid pace from the forest whence the shout had come. They were about half a mile away. Catching sight of the airship, they gave utterance to loud cries of triumph, and somewhat changed their direction. Tom at once caused the airship to rise, and by the time the Moors arrived at the spot where it had rested it was high above their heads and out of harm's way.

The Moors immediately began to scour the neighbourhood for signs of Abdul. Tom steered slightly to the left of the direction in which the lad had gone, in order still further to delude the pursuers. Not long afterwards a much larger band of riders galloped up from the direction in which the airship had come, and when they joined the former party, it was seen that they numbered at least sixty in all.

"We're rousing the whole country," said Tom with a return to his wonted cheerful manner. "If it goes on like this there'll be thousands by the time we reach the coast."

"Shall we reach it, d'you think?"

"I can't tell. The engines are good for a few miles; how many I don't know."

"Vere am I?" said Schwab, awaking. "Ach! I remember. Do ve soon arrive at ze yacht?"

"We probably shan't arrive at all," replied Tom. "One of the engines is failing."

"But it muss not-it muss not! Surely ze Photographic Sensitizer Preparation Number Six vill not fail? Schlagintwert's preparations never fail; zat is ze foundation of zair business."

"No; the preparation is all right; it's the engine."

"Ach! it should have been made in Jarmany! But, tell me true, Mr.

Dorrell, are ve in danger?"

"The truth is, Mr. Schwab, that I can't guarantee the machine for another ten miles."

"Ach! Vat vill I become? Vat vill Schlagintwert's become! Vy did you bring me in zis bad-made airship from my captivity? If you zere had left me, our Kaiser who is in Berlin vould have sent a telegram to ze Sultan of Marokko, and zen ve should see somezink. Zere had I at least enough to eat."

"Confound it!" cried Tom, thoroughly exasperated. "We came to fetch Sir Mark Ingleton, not you. But for you we should have been halfway home to England by this time; and but for your weight, we shouldn't have been in this pretty mess at all."

Schwab's jaw fell. This was an aspect of the matter that had not occurred to him. Lifting his waistcoat, and looking down, he said slowly-

"Truly I vish I had not eaten so much biscuit!"

It was now getting dark. Tom steered towards a bit of rough country to the north, again some points out of his course, his object being to worry the pursuers as much as possible and to draw them away from the line of Abdul's flight. With great satisfaction he saw them follow.

After scattering over a wide area in search of the fugitive whose disappearance had so much puzzled them, they had again formed a compact body, and pursued the airship in the belief that their quarry must still be within touch of it. In a few more minutes they were obliterated by the darkness; but the sky was starry, and while on the ground they were invisible from above, it was probable that the airship was still visible to them.

Tom had noticed for some time past that the wind, which had been slight and for the most part in his favour during the day, was shifting, and blowing with greater force. In the circ.u.mstances the airship was making very little headway, and Tom's anxieties were further increased when his sense of smell apprised him that the engines were again becoming overheated. Even if the airship were out of sight, the pursuers would probably still hear the whirring of the propellers, and it was advisable, both for the sake of cooling the machinery and of depriving the enemy of a clue, that the airship should once more be brought to the ground. But it was with some trepidation that Tom allowed it to sink. He chose a spot just beyond a stretch of woodland from which it was scarcely possible that the vessel could have been seen. He could only hope that the sound had not been heard.

"I vish--" began Schwab, as they came to rest.

"Shut up!" said Tom in a vehement whisper. "Everything depends on our keeping perfect silence now."

In a few minutes the hors.e.m.e.n could be heard approaching. They dashed past the trees behind which the airship stood, and Tom's heart beat fast as he realized how very near the danger was. But the riders did not pause, and the sound of the horses' hoofs gradually faded away.

"We'd better lie snug for a time," said Tom. "Perhaps the wind will moderate. I'm afraid the exertion of overcoming it would do for the engines altogether."

While Oliphant held the electric torch, carefully shaded, Tom again overhauled the engines.

"The valve is sticking," he said in a whisper. "There is some grit between the stem and the sleeve. It must have got in at our last stop. I shall have to take off the cover and file the stem smooth."

This was an operation of some difficulty; but as it turned out there was time to spare, for as the night wore on the force of the wind rather increased than diminished. Schwab bemoaned the lack of a pipe and beer; the others were so tired and famished that they were not provoked to either merriment or anger by his complaints. He by and by again fell asleep. Tom and Oliphant kept watch and watch throughout the night. When Tom awoke from an uneasy nap shortly before dawn, he was relieved to find that the wind had dropped, though its direction was still unfavourable. At daybreak a start was made, and for a short time the valve worked satisfactorily, thanks to the large amount of oil used to counteract the overheating. Then, however, the oil began again to give off an unmistakable odour. The airship was brought to ground, and Tom found that the injured stem had become bent. With infinite care, to avoid breaking it altogether, Tom straightened it with a small hammer, and again filed it smooth.

Once more the airship resumed its flight. Fortunately there was no sign of the pursuers, and Tom hoped that Abdul had managed to evade their clutches.

The country was very wild and deserted, and Tom purposely steered some miles out of what he thought was the true course, in order to avoid the cultivated district that lay in the direct line to the yacht. Suddenly, however, skirting the shoulder of a hill, he came into full view of a village, with the sea a few miles beyond.

"Thank Heaven!" e.j.a.c.u.l.a.t.ed Oliphant, "we may do it yet."

"Surely that's the very village you were taken to with Ingleton," said Tom, scanning the place through his binocular. "Have a look."

"By George! I believe you're right. There's a whole host of Moors round it, too. They've sighted us. They're off!"

Taking the gla.s.s from him, Tom saw a body of at least a hundred and fifty men galloping off in a direction which would bring them between him and the coast.

"Smother them!" he cried. "I wouldn't mind if we hadn't to drop so often to cool."

"Can't we make one good dash for it? We've only eight or nine miles to go, have we?"

"My dear fellow, we can't do five miles at a stretch-unless we drop Mr.

Schwab."

"Donnerwetter!" cried the German, starting up in fright. "Vat you say?

Vould you do zat? Vould you desert? Vould you leave me, a Jarman sobjeck, to be tore in piece by tousand vile Mohrs, ven ze sea, ze sea vat sails ze Jarman fleet, is so near, so near? But yes-I know it! I alvays say so. Never trust an Englishman-egzept in business!"

Tom treated this outburst with silent contempt.

"I can't go at a higher speed than fifteen miles an hour," he said to Oliphant. "We're perhaps a mile nearer the sea than the Moors, but they can equal our pace for a short distance, and I know we'll have to come down before we get to the sea. If we do, we'll be collared."

"Risk a dash! It seems our only chance."

Tom hesitated for a few moments. Then he said, setting his teeth-

"All right. It's the only thing to do."

He put both engines at full speed, and Schwab shouted with delight when he saw that the airship was gradually drawing away from the galloping Moors. But in ten minutes all three were aware of the ominous smell. Was it possible to reach the yacht, now clearly in view? Tom, alert to catch the slightest indication of failure on the part of the engines, hoped, doubted, hoped again, but was resolved to hold on to the last.

Another five minutes pa.s.sed.

Then all were startled by a strange grinding sound in the defective engine.

"What is it?" asked Oliphant.

"It's all up," said Tom quietly. "The heat has loosened the turbine blades, and they are smashing to pieces." Even as he spoke sheets of flame shot from the exhaust pipe, accompanied by a series of deafening reports.

Tom at once reduced speed, shouting to Oliphant to adjust the planes for descent.

"Zink! Zink vat you do!" cried Schwab, now almost frantic. "Zey vill have us! Ze Mohrs vill cut our zroats! Vy-vy-vy--"

Tom paid no heed; Oliphant muttered under his breath. They were sinking towards a ravine through which a watercourse ran to the sea. The engine, its parts grinding and tearing with a hideous scrunching sound, was shooting out flames, to the accompaniment of detonations like those of a Maxim gun. Another minute or two would witness a cataclysm; but Tom thought that if the farther side of the ravine could be reached, they might gain a little grace. The enemy would have some difficulty in crossing at speed.

The engines were failing; the airship was falling more and more rapidly.