This, then, was the meaning of the Kalmuck officer's veiled warning.

The enemy had taken a leaf out of the defenders' book. Their airmen, equipped no doubt with bombs much more destructive than Lawrence's home-made missiles, intended to strike at the very heart of the defence, and by rendering the mine premises untenable, clear the way for the advance of the army.

Lawrence was fortunately cool of head and a rapid thinker. After a moment of stupefaction he saw his course clearly. The danger from the air must be met in the air. This could only be done by rising above the enemy's monoplane, and hurling his bombs down upon it. The Kalmuck pilot would be as anxious as he to avoid an actual collision, which must prove disastrous to both the machines. It was wholly a question of manoeuvring for position.

The glimpse he had caught of the hostile aeroplane as it flashed by, suggested that it was a much larger and more powerful machine than his own. If this were indeed the case, he was probably quite outmatched in speed as in armament. But he saw in a moment that the possession of the smaller machine might tend to his own advantage, for he could wheel in narrow parts of the valley where the attempt would prove destructive to the enemy. Moreover, he knew the valley thoroughly; the others, though no doubt vastly superior to him in a military sense, lacked local experience and had everything to learn. Time was on his side.

As soon as he began his flight he knew that he had gained one point. If the enemy had turned at his customary wheeling-place, their aeroplane would already have been in sight. The next suitable spot was several miles farther up the valley, unless indeed they should rise to a much greater height than that at which they had pa.s.sed. Such an ascension would consume time; it would further make it very difficult for them to drop their bombs with any degree of accuracy. Whether they rose or continued their flight at the same alt.i.tude until they reached the wider turning-place, they would not be back for four or five minutes.

Lawrence resolved to utilise this breathing s.p.a.ce.

He flew on until he reached his usual turning-place, then began to mount in a spiral course. While he was doing this, two considerations flashed through his mind. If, when he met the enemy, he should be still below them, he must fly on in the opposite direction, for the chance of being hit by a bomb, when the machines were pa.s.sing at the rate of perhaps a hundred and fifty miles an hour, would be very slight. His only fear in that case was that they would fly straight back to the mine and work havoc there without a possibility of interference. If, on the other hand, he were above them, his best course would be to fly in the same direction, and try to drop his bombs on them. When two express trains are running the same way, it is possible, however great their speed, to cast an object from a carriage of one through an open window of the other.

He was still ascending when Fazl shouted that the enemy's aeroplane was in sight, at a greater height.

"Rifle!" said Lawrence instantly, as he headed up the valley.

The Gurkha fired, as the two machines rushed at terrific speed towards each other. There was no reply, but a few seconds afterwards an explosion in the valley below showed that the enemy had dropped a bomb.

It would have been almost a miracle if it had hit the aeroplane in the fraction of a second of the pa.s.sing. But a second explosion a little later was very perturbing. Unless he could check the enemy, they might sail over the mine again and again, and on the wider target which that presented take surer aim. Luckily they would have to fly several miles down the river before they could again turn, and the few minutes' grace might give him time to ascend still higher, and attain an alt.i.tude at which he would have the advantage.

As the machines pa.s.sed, Lawrence had had time to confirm his impression that the other aeroplane was much larger than his own. He saw too that it was occupied by three men. But these elements of superiority would be to some extent neutralized by the greater handiness of his own machine in navigating the narrow gorges of the valley. The situation demanded a readiness to take risks. The gorge to which Lawrence had now come after pa.s.sing the enemy was so constricted that in ordinary circ.u.mstances he would never have dreamed of attempting a turning movement. But he felt the supreme necessity of wheeling at once, in order to return to the "bay" which he had lately left. There he might do something to protect the mine, if only by diverting the enemy's attack upon himself. He might also have an opportunity of rising to a sufficient height for offensive purposes.

Choosing the widest part of the gorge, he banked his machine up, and clearing the cliff apparently by inches he swept round again to the north. When in half a minute he reached the turning place, the aeroplane was not in sight. But he heard sounds of a fierce struggle beyond. The bombardment had ceased, but the air was filled with the crack of rifles, the rattle of the machine gun, and the shouts of men.

He could do nothing to help his brother. There was not even time to fly on and drop a bomb among the enemy: he must utilise every moment in preparing for the return of the aeroplane. He steered his machine in a series of short spirals, rising as rapidly as possible, watching the valley northward anxiously. As yet its windings concealed the enemy's aeroplane from view. It was an inexpressible relief to him that they had not attempted to turn at the spot where he now was. They had not thought it practicable, or not had the time; probably they had shot by before even the possibility had occurred to them.

He swept round and round in his corkscrew flight, rising gradually until he was more than two thousand feet above the river. His view was now greatly extended, and when the larger aeroplane came in sight from round a bend nearly a mile away, he saw with a flash of hope that it was now lower than his own machine, although somewhat higher than before.

Evidently the airmen had foreseen that he might rise in order to avoid their bombs, and sought to forestall him; but his narrow spiral had carried him up to a greater height than their two long inclined planes.

The moment he saw them he started straight to meet them. Nothing could have been better calculated to a.s.sist his brother in the desperate struggle on the track. It was as when a charging bull is diverted from the object of his fury by the fluttering of a handkerchief or a newspaper within his range of vision. The Kalmuck airmen recognised that they had an opponent with whom they must seriously reckon; and though perhaps their general, looking on from below, would have bidden them to ignore the aeroplane, and pursue the more important duty of shattering the defences, they no doubt thought that a few minutes' or even hours' further delay would be less disastrous than the destruction of themselves and their machine. When the defenders' aeroplane was out of action, the rest would be easy.

Lawrence had resolved not to imitate the enemy in hurling a bomb while the machines were flashing past in opposite directions. His missiles were too precious for one to be wasted. As the aeroplanes met, he heard two cracks, followed by two metallic thuds on the iron plates below his cha.s.sis: the enemy had fired. What effect their shots had he knew not, but neither the engine nor the occupants suffered any injury. He had already commenced a turning movement. Completing his circle, he steered straight after the enemy, who were heading directly up the valley.

There had been no explosion on the track or in the mine compounds as they pa.s.sed: so far his tactics had justified themselves.

But Lawrence had not been more than a few seconds in pursuit before he found that in speed his machine was utterly outcla.s.sed. The enemy seemed almost to leave him standing. This was not unexpected; but as soon as he was sure of it he felt that his course of action was clearly marked out. It would be a fatal mistake to give the enemy enough air-room to take advantage of their superiority. If they got plenty of s.p.a.ce for manoeuvring they could rise as far above him as they pleased, and either shatter the aeroplane with a well-placed bomb, or, having two rifles to one, could wait an opening for a shot that would incapacitate himself or Fazl, perhaps both. He must devote all his energy and skill to dodging and deluding the enemy, attacking them if occasion offered, in any case keeping them constantly employed. Their engine must consume a much larger quant.i.ty of petrol and lubricant than his. They must have used up a great deal in flying from their starting-place--Tash Kend, he presumed--and it was unlikely that there was any supply with the army at the end of the valley from which they could replenish their tanks. If he could only manoeuvre so as to starve them out of fuel, all their superiorities would be nullified and their usefulness would have vanished.

It was a question now of calculating chances, or rather of guessing--like the children's game when one brings his closed fists from behind his back and asks another to guess which hand holds the concealed object. When the two aeroplanes were out of sight, the occupants of neither could know what the others were doing. They could only make a random shot at the probabilities. Lawrence felt pretty sure that the enemy would seek to rise to a greater alt.i.tude than they supposed him to be attaining. He therefore decided to descend at once, and hover in the lower part of the valley. A long vol plane northward brought him within a short distance of the struggle going on at the bend. As he sped by, he ordered Fazl to drop a bomb among the enemy beyond the breastwork, then swooped past, three or four hundred feet above the river, turned at the first possible spot, and flew back to meet the enemy. As he expected, they had risen to a great height. Flying low as he now was, they were probably two thousand feet above him. When they saw him, they at once began to descend; but the machines were rushing in opposite directions so swiftly that the vertical distance between them was lessened by only two or three hundred feet when they met. A few seconds after they had pa.s.sed, Lawrence heard two explosions, and Fazl reported that the enemy's bombs had fallen, one in the river, the other on the cliff-side. Again they had missed their aim.

Lawrence knew that they could not return within fifteen minutes. While it was important to him that they should waste their petrol, it was equally important that he should husband his, for he had very little left at the shed. It occurred to him that there would be time to alight on the platform, run to the mine to see how things were pa.s.sing there, and get back in time to fly off before the enemy came in sight. He therefore wheeled round at his usual place, and in less than a minute slid gently on to the ledge. Leaving Fazl to look to the engine, he ran along the pathway, and on turning the corner saw with some astonishment that hostilities had apparently ceased. The breastwork was still manned by Bob and his party: Lawrence almost winced as he noticed how large a number of bodies lay prostrate around them. The enemy were invisible: it seemed certain that their attack had been repulsed.

The mine compounds were deserted, except by Gur Buksh and two other men, whom Lawrence recognised in a moment as Chunda Beg and Shan Tai. These three were reclining against the wall near the machine gun. Every other fighting man had crossed the bridge to bear his part in the holding of the track. Lawrence felt a thrill of pride in the courage and loyalty of the cook and the khansaman, who, house servants as they were, often held in scorn by the warriors, had in this hour of peril given their a.s.sistance to the steadfast havildar.

He hurried on to the compound, noting as he pa.s.sed the havoc wrought by the one bomb from the hostile aeroplane which had hit the mark. Gur Buksh and the others saluted as gravely as if it were the prime of peace.

"What has happened?" asked Lawrence breathlessly.

The havildar related how the appearance of the enemy's aeroplane had been the signal for a more ferocious bombardment than had before taken place. When the breastwork was half ruined by the sh.e.l.ls, a swarm of Kalmucks rushed to the attack with yells of antic.i.p.ated triumph, while the defenders, who had remained in comparative safety some distance away, leapt back to their places at the shattered rampart. The enemy, coming unawares on the wire entanglements, had been thrown into an unwieldy and disordered ma.s.s; and after a few minutes of desperate efforts to break through the obstacle, with partial success, they had been so withered by the defenders' fire that flesh and blood could endure no more. They had fled, a confused rabble, to their own entrenchment.

There was no time for Lawrence to hear more, or to discuss with the imperturbable Sikh any measures that might be devised to a.s.sist the heroic fighters on the other bank. He knew well that the check could be only temporary, and could not think without distress of the issue of the next attack. Hurrying back to the ledge, he and Fazl got into their places, ready to fly off directly they heard the returning aeroplane.

The Gurkha's ears first caught the throbbing drone, and as the machine once more rose into the air, the field guns recommenced to bark and spit.

As soon as Lawrence reached his turning-place he began to climb. In a few moments he caught sight of the enemy's aeroplane skimming round the bend below the mine. It was much lower than before, probably no more than three hundred feet above Lawrence, and as soon as the airmen caught sight of him, they dipped so suddenly as almost to suggest that the machine was beyond control. But Lawrence realised that the descent was intentional. They meant to come as close above him as they could in the half mile between them. He ceased to mount, and steered straight down the valley, hugging the cliff on the left hand. The enemy followed his manoeuvre, edging to their right in order to pa.s.s immediately above him.

The two aeroplanes were only about a hundred yards horizontally apart when with a quick movement of his rudder, which threw a hazardous strain upon the planes, Lawrence shot out over the river. Before the enemy could alter their own course he had pa.s.sed well outside them. Their bombs, dropped hurriedly while the pilot was striving to cope with Lawrence's sudden movement, fell harmlessly into the river.

The enemy's turning-place up stream being much nearer the mine than that in the opposite direction, there was no time to alight again and save expenditure of petrol. But there was time to lend aid to the defenders at the breastwork. Lawrence flew on, instructing Fazl to hurl a bomb among the enemy as he pa.s.sed the bend. Two teams of horses were dragging more field guns up to the rampart. It was among these that Fazl let fall his bomb, and looking back, he shouted gleefully that one of the teams had stampeded and dashed with their gun over the bank into the river, while the other were plunging furiously amid a smother of smoke.

At the same time the rattle of the machine gun announced that Gur Buksh was again at work.

Lawrence did not wish to fly six or seven miles down the river to the wide bay in which he was sure the enemy had turned. To wheel round earlier involved some risk, but it was a risk from which his strung-up nerves did not flinch.

About three-fourths of a mile beyond the bend, at the spot where the enemy had established themselves after their first repulse, the gorge curved to the west, and in the cliff-face there was an extensive depression, scooped out as it were by a landslip. He resolved to try his luck there. The margin was perilously narrow, and only a man absolutely familiar with the spot, as he was, and prepared for the turning movement at the very moment of reaching it, could have hoped to wheel in the s.p.a.ce.

At the critical point he banked up at a sharp angle, and for one brief moment felt a cold shudder of fear as he recognised the beginning of the sideslip that had brought disaster on so many reckless or unfortunate airmen. But the planes recovered their grip; the machine swung round across the river, having shaved the cliff on the left by an appallingly fine margin; and flew lightly and evenly up stream again.

By this daring feat Lawrence had saved nearly ten miles and the equivalent quant.i.ty of petrol. He had also avoided a meeting with the enemy on the north side of the mine, where manoeuvring to dodge them would have been much more difficult. By alighting when they next pa.s.sed him he would again save while they were expending, and however large their supply had been when they started, it could not much longer stand the drain of continual flight up and down the river. Even now, since entering the valley, they must have travelled a good deal more than a hundred miles; their flight from headquarters might have been three hundred. No doubt a further supply of fuel and oil had been despatched after them, but it would take a week or more to reach them over such rugged country. If he could only keep them fruitlessly employed until they were forced to leave the gorge through failing petrol, he would gain perhaps just enough time for the garrison to prolong their defence until the expected relief force arrived.

Thought is quicker even than an aeroplane's flight: these hopes, conjectures, volitions flashed through Lawrence's mind in the interval between his venturesome circuit and his arrival at the bend. The bombardment had recommenced. Two guns had been got into position; others were being hauled up the track. A hot rifle fire was opened upon the aeroplane, and both pilot and pa.s.senger were struck by fragments of bullets that had splintered on the metal work. Their great speed soon carried them out of further danger, but the bomb which Fazl dropped missed its aim, exploded on the rocky bank instead of on the track, and did little harm.

Lawrence guessed that the Kalmuck airmen would now suppose him to have risen, and would themselves be mounting in order to keep above him. He therefore resolved to keep low. The sequel showed that the enemy had been cunning enough to guess at his guess. When they reappeared, so far from ascending they were descending, yet gradually, so that they might adapt their course to the exigencies of the moment. They were now only two hundred feet above him.

This time he decided not to rush past and continue his flight up stream, but to wheel at the turning-place, and save time and petrol by flying back in their wake to his platform. He realised afterwards that he began his turning movement a trifle too soon, though, as the event proved, his indiscretion served him well. The enemy had not quite met him when he shifted his rudder for circling round the bay. He expected them to flash by as usual at express speed, but to his intense astonishment and alarm he found that instead of continuing on their direct course they had suddenly banked over, and were wheeling above him in the same direction as himself. It was a manoeuvre of extraordinary daring, for the larger aeroplane required a much wider circle than the smaller, and in order to clear the cliffs it had to remain banked up at a dangerously sharp angle.

Lawrence felt himself trapped. He could not fly out at either end of the bay, he thought, without being immediately followed by the enemy, who would then have him at their mercy. Yet he was in equal danger if he remained circling below them, for though their flight was swifter than his, at some moment their machine would be vertically above him, and they would doubtless seize that moment for hurling a bomb. He could not descend without shattering the aeroplane on the banks or plunging into the river. He felt as helpless as a pigeon beneath an eagle.

It was indeed an extraordinary situation: two aeroplanes wheeling round and round in a cup-like hollow, with less than two hundred feet of s.p.a.ce between them. The Kalmucks had not as yet fired or dropped a bomb: Lawrence imagined them gloating over their helpless victim, awaiting a favourable moment for one crushing stroke. The first shot was fired by Fazl; the enemy replied, but instead of keeping up a continuous fire, they ceased after a few shots, which riddled the planes, but hit no vital part. Lawrence wondered at their abstinence, until, following them with his eyes, he had a sudden conviction that they were in difficulties. The machine was banked up to the extreme limit of safety, and it flashed upon him that the enemy, and not himself, were caged.

They could not ascend, for, a few hundred feet above them, the cliff on the west side of the stream hung forward in a jagged bluff that came within the circle of their flight. Contact with it would hurl them into the river. Nor could they leave the bay by either of the exits north or south without the risk of colliding with the cliffs, for the s.p.a.ce was so narrow, and the speed of the machine so great, that the movements necessary for unbanking and steering could hardly be performed in the fraction of a second between their quitting the bay and running into the straight. It is one thing for a wasp to fly into a bottle, and quite another to fly out again.

The machines had completed several circles before Lawrence had grasped the situation. During this time Fazl had been steadily firing, but the enemy had been silent. Suddenly the Gurkha uttered a shout; one of the Kalmucks fell from the aeroplane, and whirled over and over in the air until he struck the river and disappeared.

"Don't fire again!" cried Lawrence.

He had become conscious that the perpendicular distance between the two planes was rapidly diminishing. The enemy's engine had not failed; their speed was the same; yet it was plain that moment by moment they were drawing nearer to the plane below. If the machines had been ships, Lawrence would have been tempted to believe that the enemy were trying to board; but he knew that a collision would be fatal to both. He was at a loss to explain the strange movement; indeed, he had little time to think of it, for he realised that unless he himself made his escape, his machine would be soon hurled to the bottom by the impact of the larger.

He had not found it necessary to bank so much as the Kalmuck pilot. His lesser speed and the greater handiness of his aeroplane enabled him to fly out at the exit without the almost certainty of dashing against the cliff. At his next round he steered straight through the northern gap, and flew back in a flush of wonder and excitement to the platform.

As he expected, the enemy did not follow him. Alighting he rushed to the projecting b.u.t.tress and gazed up the valley. He could see the doomed aeroplane as it flashed across the opening of the bay. It was still whirling round and round, but falling, falling with ever increasing velocity. He shuddered with horror as he contemplated the inevitable end. He did not witness the actual close of the tragedy. The aeroplane as it neared the bottom was hidden from him by the rocky banks of the river. But half a minute after he himself stood in trembling safety a tremendous explosion shook the ground, and a cloud of smoke and broken rocks shot high into the air. Then there was a burst of flame, and he knew that all was over.

Overcome with sickness at the terrible end of these gallant airmen, and with nervous exhaustion after his own wearing efforts, he lay flat on the rock to recover his composure. Thinking over the recent scene, he hit upon a conjectural explanation of the uncontrollable descent of the enemy's aeroplane. He supposed that, with the machine so critically banked up in order to navigate the narrow cup, the pilot had been quite unable to make those delicate adjustments of the planes and the elevator that were necessary to counteract the dragging force of gravity. Later on, when he had an opportunity of discussing the matter with his brother, Bob scouted his theory, declaring that while the petrol lasted nothing could have prevented the machine from whirling round and round.

But Lawrence stuck to his opinion, and Bob very naturally declared that it was not a matter he would care to put to the test.

CHAPTER THE TWENTY-SEVENTH

AD INFIMOS

Just as the ticking of the household clock is unnoticed, but its cessation is immediately remarked; so it was not until the coughing roar of the field guns, which had continued ever since Lawrence last soared over the bend, suddenly ceased, that he was roused to full consciousness of the critical situation at the mine. Springing up, he ran with Fazl along the pathway until he came to a spot where the whole theatre of the combat could be viewed.

The noise of the guns had been followed by a hoa.r.s.e babel of cries mingled with the crackle of rifles. He was just in time to see a swarm of Kalmucks surge over the breastwork, and Bob with his devoted band rushing up the track to the second rampart a hundred yards away. The machine gun beneath the north wall of the mine was silent; n.o.body was to be seen in the compound; and Lawrence's heart sank with dread lest the gun had been smashed, and Gur Buksh and his voluntary a.s.sistants slain.

In a moment, however, Fazl drew his attention excitedly to three men lying flat on their faces upon the drawbridge. He recognised them at once as the havildar, Shan Tai and Chunda Beg. But what were they doing?

Their arms were moving swiftly this way and that, like the arms of tailors sewing.