The Secret People

CHAPTER I

On an afternoon in September 1964, the ears of the inhabitants of Algiers were unpleasantly assaulted by an uproar from the skies. The sound was different from the familiar drumming boom of the regular mail and passenger service, and it was equally unlike the staccato throbbing of the desert police patrols; it was, in fact, an entirely new brand of aerial noise, more offensive than either. The strollers in the streets stopped to look up, the loiterers in cafes moved from under their striped awnings, even the hagglers in the markets momentarily suspended business to stare surprisedly overhead.

The cause of the sensation came streaking across the blue Mediterranean—a small silver aeroplane, hurling itself out of the northern sky. It amazed the watchers that so small a craft could make so fierce a noise, but the sight of it astonished them no less, for it roared through the heavens, trailing behind it a wake of flame fully six times its own length. It was diving as it crossed the city, coming down to earth like a silver comet with a scarlet tail. A moment later it had passed out of sight. The crackling roar of its engines grew less and presently ceased. Algiers, with a few caustic censuals of the noise-loving pilot, turned back to its business and its drinks, and forgot the silver plane's existence.

Mark Sunnet taxied the plane to a stop and emerged from his cabin to greet the astonished aerodrome authorities. He was polite to them, but not expansive. He had grown weary of the sensation which inevitably attended his arrivals and departures, and frequent explanations to interested authorities of the superiority of his machine over the ordinary propeller-driven craft had become tedious. Accordingly, he pleaded tiredness. He had flown, he told them, non-stop from Paris, and proposed spending only one night in Algiers before pushing on to the south. Could anyone, he added, recommend him to a comfortable hotel? A member of the aerodrome staff suggested that the Hotel de Londres could provide hot baths, comfortable beds, and excellent food. He thanked the man, gave instructions for the care of his plane, and, leaving it still surrounded by a crowd of inquisitive pilots and ground staff, made his way to the Customs Office. Emerging a few minutes later with his papers stamped and in order, he hailed a taxi.

'I want to go to the Hotel de Londres,' he said.

The driver expressed surprise in a theatrical manner.

'The Hotel de Londres, monsieur?' he inquired doubtfully.

'Certainly,' said Mark. 'What's wrong with that?'

'Alors, monsieur. It is a good hotel, no doubt, but not of the best. It is bourgeois. Monsieur has not the bourgeois air, that is evident. He should honour the Hotel de l'Etoile, there is not a doubt of it. It is a house of the most magnificent, it is modern, it is-'.

'All right. Let's have a look at it.' Mark cut the eulogy short by climbing into the cab.

Fate is not above using inconsiderable details for her obscure purpose. Thus, the whole of Mark's future was destined to depend on the trifling fact that an Algerian taxi-driver was brother to the head waiter in a hotel.

Five days later found him, still a guest of the Hotel de l'Etoile, lounging at ease upon its broad balcony. He lay with his head turned at an angle which enabled him to watch the occupant of the next chair. The busy harbour of Algiers, lively and brilliant in the sunshine, backed by the deep blue of the Mediterranean was a panorama which could wait: for the present, Margaret claimed all his attention. He half hoped that she would not wake to disturb his placid comfort.

It was a long time since he had been allowed to indulge in the luxury of complete laziness. Of the last six years, business had occupied almost every waking hour. He had devoted himself doggedly to the uninspiring task of propping up a tottering shoe business which only the timely death of an unprogressive uncle had saved from complete disaster. The firm of Sunnet had been established over a century and had retained in the trade a reputation for turning out good, reliable stuff. And that, the uncle, an inveterate recliner upon laurels, had considered to be good enough.

The prospects of salvaging the hopelessly old-fashioned firm had been slender when Mark inherited. Almost without exception his advisers had been for selling to cut his losses, but Mark had developed a streak of obstinacy which surprised himself. He had found himself looking at the rocky business of Sunnet's not merely as a means of livelihood, but as a challenge, and he went to work as much in a spirit of bravado as from hope of gain.

He had not been brilliant, but he had shown an obstinate determination to overcome prejudice against the firm. Gradually the trade became aware that Sunnet's was no longer a back number; their shoes were once more being demanded and worn by the million, and Mark emerged from the cocoon of work which he had spun about him to find himself not only vindicated, but a man of means. And this was the time to slack off. He had no intention of devoting his life to shoes, nor to the making of money from shoes. He had done what he had set out to do, and with the concern forging ahead, he felt the need of personal freedom. He had called his managers together and told them that he intended to go away for a while.

'Finding new markets, sir?' Ae chief buyer inquired hopefully.

'God forbid. I'm going to have a holiday—a real holiday. And I'm not leaving an address. It'll be up to you fellows to manage things between you while I'm away.'

His first step had been to buy a machine lately imported from America. The makers, unromantic men of little imagination, had been able to find no better name for their product than 'Strato-Plane'. Mark, after one flight in it to those regions far above the clouds, renamed it the Sun Bird; and the Sun Bird it remained.

The first three weeks of his new leisure he occupied in trans-European flitting. Paris, Copenhagen, Stockholm, Warsaw, Berlin, Vienna, Paris again; hither and thither with all the delight of a child in a new toy until he tired of fast movement for its own sake and began to contemplate a less hurried, though more extensive, trip. The Sun Bird's flying range was immense and the world lay open to him. There was little sense in restricting himself to Europe where one large city was, after all, not very unlike another, when he had the time and the means to range as far as he wished. Moreover, he found himself growing a trifle tired of his own exclusive society. Accordingly, he had bethought him of a friend now farming in Cape Province, and the Sun Bird was turned to the south.

But now his intended trip had been cut short before it had well begun. His proposed stop of one night in Algiers had already been multiplied by five, and looked like extending still more. And the reason for his change of plan was reposing in the chair beside him.

Her head lay back on its deep red curls against a cushion, and her slender, sun-browned hands rested, fingers interlocked, in her lap. Her face, too, had acquired a tinge of golden brown and the African sun had raised upon it the faintest scatter of shadows—scarcely dark enough to be called freckles. Mark approved critically. Many of the red-haired girls he had known, he reflected, had had an unsatisfactory, a kind of unfinished look about the eyes, but there was no trace of that in Margaret's face. The hazel eyes themselves were hidden now behind lids trimmed with perfectly genuine dark lashes. Her mouth, not too large, but certainly without any petulant smallness, was curved in a slight smile. The smile increased as he watched. The lids lifted.

'Well, do you approve of it?'

Mark laughed. 'I thought you were asleep.'

'Most women know when they are being inspected.'

'Then you can never really sleep in public.'

'Thank you, sir.'

She smiled at him again and stretched her arms lazily. Mark swung his legs to the floor and sat up, looking out into the hot sunshine across the shimmering water. Both of them felt that it was time to make a move, but the day did not encourage activity.

'What shall we do?' he asked her.

'I don't know. You suggest something.'

Mark reflected. The tennis courts were not far away, but they would be simmering like hot-plates on such a day. There was the swimming pool; or they might go a little way up the coast and bathe, or . . .

'What about the New Sea? We've neither of us seen that yet.'

She turned, surprised.

'But it's ever so far from here—right beyond the mountains. Three or four hundred miles. Even in a plane-'

'In an ordinary plane it would take some time,' he agreed, 'but not in my Sun Bird. You wait till I show you. It's just an afternoon jaunt for a rocket plane.'

'A rocket plane? Like the new American mail carriers?'

'Well, hardly as big as all that, but she is a rocket plane. There aren't many of them about yet, but there will be soon: they're the coming thing, not a doubt of it.'

The girl looked doubtful.

'But are they quite safe?'

'The Sun Bird's taken me safely enough all round the continent and brought me across here. Besides, do you think I'd suggest your going in her if she weren't the safest thing in the skies? You wait till you see her. Hurry up and change, then I'll show you.'

Margaret Lawn made her way obediently towards the lift. The business of changing she performed almost automatically, using her mirror with an unwonted perfunc-toriness. Her holiday was progressing in an expected and yet in an unexpected manner. Mark, for instance, had not been entirely unexpected—not that she had ever seen or even heard of him before, but the occasion was bound to provide a playmate of some kind. He might have been called Tom or Dick or Harry: he happened to be called Mark. Nevertheless, the state of affairs at present was not quite as she had foreseen. Events were not proceeding quite according to the course plotted for them. She had a sensation as though she were trying to steer a car with a wheel which had too much play. One got along without accidents, but there was an unwonted breathlessness, an unusual lack of assurance. More disturbing she found the growing conviction that she did not want to steer, and that it no longer amused her to apply the manoeuvring skill which she had displayed on previous occasions. This was the more irritating in that there was nothing striking about Mark to account for it. He was really a perfectly ordinary young man, and Margaret, like many another, had not felt that she was destined to fall in love with an ordinary young man. And yet it was happening—had happened. She was irritable with herself. She, Margaret Lawn, who had hitherto with justification considered herself reliable, capable, and a mistress of difficult situations, was undergoing an unwilling change; realising, with feeble protest, that she quite incredibly wanted to hand over the controls. Changing, full in the face of all her principles, from an active to a passive: and, worse still, half enjoying the change.

It did not take her long to slip off her light frock and put on more serviceable clothes. In general—that is, apart from present emotional uncertainties—she was a young woman who knew her own mind and disdained the more elementary tricks. Her reappearance on the balcony was made with little delay.

'Will it do?' she asked.

Mark rose from his chair and looked at her neat white riding suit with approval.

'My dear, it couldn't be better. Even if it wouldn't do, it suits you far too well for me to say so.'

They took a taxi to the aerodrome where Mark's orders for his machine to be wheeled out set the mechanics bustling.

Rocket-propelled planes were still such a novelty that his was the first to be seen in Algiers. A few were in experimental service upon the mail routes, but the general public knew them only from photographs. A privately owned stratosphere rocket was all but unique upon the eastern side of the Atlantic, and as she was drawn clear of the hangar most of the ground staff within sight hurried to lend interested assistance.

'And that's your Sun Bird}' Margaret said, watching the attendants trundle the little plane into the sunlight.

Mark nodded. 'How do you like her? Looks a bit quaint at first sight, I'll admit.'

'I think she's lovely,' the girl answered, without moving her gaze from the glittering silver shape.

The Sun Bird's proportions differed noticeably from those of propeller-driven aircraft. Her fuselage was wider and decidedly shorter, and the wings stubbier and broader. Two windows were set right in the nose and others well forward in the sides. Despite the unfamiliar shape caused chiefly by new problems of weight distribution, there was no effect of squatness: she looked what she was, a compact little bundle of power, as different from the ordinary plane as a bumble bee from a seagull.

Mark made a short investigation—somehow he never managed to feel as easy about foreign mechanics as he did about the home variety—but he found no cause for complaint. The fuel tanks were full and all the necessary adjustments had been faithfully made. He unlocked the cabin door and slid into the driving seat, beckoning the girl in beside him. She followed and looked round with interest. The two seats were set side by side right in the nose. In the small cabin was room for more seats behind them, but either these had never been fixed, or Mark had had them removed. Against the sides was a series of lockers and cupboards, and to metal staples set in the floor and walls were attached straps for the purpose of securing any loose baggage.

Mark was shouting final instructions to the ground staff, warning them to stand well clear unless they wished to be grilled. Then he slammed the door, cutting off all sound from the outer world. He advised Margaret to lean her head against the padded rest behind her seat.

'The acceleration's a bit fierce when we take off,' he explained.

She leaned back obediently, and he looked out of the window to make certain that the men had taken his advice to heart.

'Right. Here we go then.'

He gripped the stick with one hand, and with the other advanced a small lever set in the left arm of his seat. A roaring drone broke out: a cluster of fiery daggers stabbed from the bunch of rocket ports in the tail. The whole sturdy little ship shuddered and jumped. Then she was off, hurtling across the field, spitting flames behind her. Margaret felt as if a great invisible weight were pressing her back into her seat.

Suddenly the Sun Bird seemed to leap from the ground. Nose up, she soared, climbing into the blue African sky at an angle which caused the watching ground staff's jaws to drop. For a few minutes she was visible as a glitter of steel and a flash of fire in the heavens, then she was gone, leaving only a trail of smoke to show her path.

The chief mechanic shook his head; the Sun Bird struck him as being a bit too new-fangled, he felt no temptation to ride on a roaring rocket. His comrades were agreeing among themselves that her climb was magni-fique, but that the din of her discharge was epouvantable.

Mark flattened out at twenty-one thousand feet and turned the nose to the south-east. He smiled at the girl.

'Like it?'

'It certainly is the last word in lifts, but I'm not quite sure that I really like it. I'm not frightened, but—well, it is a bit breath-taking at first, isn't it?'

'You soon get used to that.'

They had to raise their voices only slightly, for the makers had lined the hull with an efficient sound-deadening material, and the windows consisted of double sheets of non-splintering glass with a semi-vacuum between. The result was to reduce the roar of the rocket discharges to no more than a constant, muffled drone.

'Look down there,' Mark said.

A view of the North African coast bordering the vivid Mediterranean was spread for them. At such a height, no movement was visible. Land and sea were laid out in the sunlight, looking oddly artificial; like a vast, brilliantly coloured relief map beneath a huge arc light. The blue was cut off sharply by the green of the coast, which gave way gradually to the darker hues of the mountains to the south. To Margaret's unaccustomed eyes the plane was suspended almost stationary above an untrue world.

'Are we moving at all?' she asked.

For answer, Mark pointed to the speed indicator. The needle was hovering around the two-hundred mark, and she could see that it was slowly making its way higher.

'It's the height,' he explained. 'If there were any clouds about, you'd realise our speed. As it is, you can't, but you should be getting your first glimpse of the New Sea within the hour.'

The tall peaks of the Tell Atlas rose before them and Mark sent the Sun Bird soaring higher still. The speed increased as the resistance of the thin atmosphere outside grew less. He glanced at another instrument for assurance that the air supply was maintaining correct pressure within.

The mighty range of mountains now looked like a badly crumpled cloth far below. Before long the broad Plateau of the Shotts slid into view, the lakes upon it glittering like pieces of broken mirror casually dropped among the mountains. Beyond, on the starboard bow, sprawled the final spurs of the great Atlas range, the Saharan Atlas, the walls of the desert, where they ended stood the ancient town of Biskra, still guarding, as it had for untold centuries, the pass to the north. Mark changed his course a few points east. And then, as they cleared a range of lesser mountains, came their first view of the latest wonder of the world, the New Sea.

The idea of the New Sea was not in itself new. Back in the nineteenth century the great De Lesseps—previous to his entanglements over the projected Suez Canal—had started his countrymen toying with the New Sea scheme much in the same way as the English played with the idea of a Channel Tunnel. Then, after being for almost a century a matter of merely academic interest it had, in 1955, suddenly become practical politics. The French, in fact, decided to Hood a part of the Sahara Desert.

That the undertaking was within the range of possibility had long been admitted by many experts, but until France had discovered Italy's willingness to enter into partnership, the financial obstacles had proved insurmountable. Through mutual assistance and for their mutual benefit the two nations had gone to work upon the most ambitious engineering scheme yet projected.

Nature has chosen to frown upon many parts of the world, but in few places has she glowered more fiercely than in North Africa, and it would seem likely that the centre of her disapproval in that region was Tripolitania. There would be difficulty in finding an equal-sized piece of land with a better claim to the title of world's worst colony. There was little more than a strip of fertile coast closely backed by the most hopeless of deserts, but for all that the Italians, for reasons of pride and prestige, had clung to it with a magnificent obstinacy. And now the French scheme offered them the opportunity of turning a liability into an asset.

France could foresee in the creation of this inland sea several advantages for herself First, she hoped that southern Tunis and a part of Algeria would benefit. The New Sea was to be begun by merging the Tunisian lakes—or 'Shotts—which were already below sea level. It was argued that the land about it would rapidly become fertile. Trees would grow, clouds would follow, bringing rain; the rain would induce still more vegetation, and so on until the erstwhile desert sands should bloom. Moreover, Tripolitania, lying on one shore of the sea, would also benefit, thus she would be enabled to support colonists from Italy and so lessen the dangerous condition of overpopulation on the other side of the Alps. Italy, once satisfied that there was no catch in the plan, became equally enthusiastic. If her barren property should become fertile, at least in part, colonial expansion would give her a chance to build up a yet larger population. The great day when the might of the Roman Empire should be revived would be brought a step nearer.

The conferences between the two nations were remarkable both for their rapidity in making decisions and for their lack of discord. Early in 1956 the work was put in hand, and the enterprise was pushed forward with such determination and success that in March 1962, water began to gush from the first of the great pipes into the sandy waste.

Now, in September 1964, the lakes, large and small, were already merged. Seen from the air, one great shining sheet of water stretched out of view to the east and to the south. Here, in the north-west corner, the sea would not extend a great deal farther. Already it was lapping at the lower slopes of the foothills, and though its level would rise, its advance would be small. The new coast was dotted with patches of high ground still above the flood level; temporary islands soon to be submerged. Over the lower parts the water had already risen until only bunches of green palm heads broke the surface, looking like beds of reeds.

Mark put the Sun Bird into a dive and they crossed the water's edge close to an Arab village of white, flat-roofed houses. It had stood upon a slight knoll, but already the water was creeping in through the doors of the highest dwellings, while the lower could be seen, still standing, beneath the surface. They would not last long, he reflected. Built as they were, for the most part, of baked mud, they would soon revert, crumbling and sliming away to leave no sign save a few stones. There was something desolate and unhappy about this village, condemned after centuries of sunny existence to a watery dissolution. A faint sense of depression touched the two in the plane.

'It makes everything seem so impermanent,' Margaret thought aloud. 'It's like destroying a piece of history. I know it's silly and sentimental to feel like that, but I do. For hundreds of years people have lived and fought here—camel caravans have plodded across these sands; and now they'll never do it again.' She paused, and then added: 'It's the irrevocability of it, I suppose. There's always something sad—and rather frightening—when one thinks of things as irrevocable.'

Mark caught her mood and agreed with it.

'Yes. There will be new towns of flat, white houses by the new shores. They'll look the same, perhaps, but they won't be the same. The air of changelessness will have gone for good—you can't inject history. It's a funny thing that we always see the past through rose-coloured glasses, unless we really set out to get at the truth.... I mean, that village was undoubtedly squalid, life was hard in it and probably cruel, yet one regrets its passing. A queer streak of conservatism we've all got.'

He drove the plane still lower, passing over a grove of palms which bore their dates though the trunks were now awash. Children had climbed the trees to gather the last harvest they would yield, dropping the fruit down into crude boats moored below. They looked up and waved to the plane as it passed.

The two flew on for some minutes without speaking. The New Sea stretched beneath them to the horizon now in every direction, save the north. Mark pointed to the mountains which held it back.

'One day they'll build a pleasure city on those slopes, and all Europe will come here to bask in the sun and swim in the sea. I shall be there. And you?'

She considered, smiling slightly.

'It may be a long time to wait. Suppose I get old and ugly before they've built their city?'

'My dear, don't be blasphemous. There are still some impossibilities even in this world. Older you must certainly get, but ugly ... Margaret, if you should live to be a hundred, it couldn't happen ...'

At its eastern end the sea ran back in a narrow arm towards the source. Before long the Sun Bird came within sight of the twelve vast pipes which fed it. For two and a half years now they had been at their work of pouring foaming, man-made cataracts into the desert. Day and night the stupendous pumps, twenty miles away in Qabes, had sucked up their millions of gallons to send them churning and swirling along the pipes. But huge as the conduits were, it remained unbelievable that they alone could be the instruments for submerging all these square miles of land; that it was only water passed by them which was lapping ever higher and farther across the sands. The loss by evaporation alone, Mark considered, must be immense in this region. There was no day during which the sun did not broil down with full intensity to draw up its tons of moisture. From the beginning there had been sceptics who had looked on the plan as a fantasy, and he felt bound to admit that had he seen this place before the start of operations, he would have been one of them. The immensity of the task was stupefying; yet it was succeeding in a way which caused the engineering triumphs of Panama and Suez to dwindle into insignificance. Whether the ultimate results would justify its sponsors remained yet to be seen.

They passed over the gushing outlets, following the twelve-fold pipe-line across higher country, and it was a matter of only a few minutes before Qabes came into view. Both of them were somewhat prepared for the sight by the photographs which had appeared in every illustrated paper, but the scale of operations took them by surprise. It had been necessary not only to build enormous housings for the pumps and gear, but to alter the town itself. It was no longer an Arab town which lay beside the Gulf of Qabes. Smoke, noise, and fuss reeked up to insult the African sky from a city which might have been transported bodily from one of the less pleasant industrial districts of Europe. If ever a place deserved to be called a blot on the fair face of nature, it was the transformed town of Qabes.

But one had to admit that a job was being done, and done well; it was to be hoped that the end would justify all this filth and furor which was the means. Head-cloth had been ousted by cloth cap, tractors and cars had supplanted camel and donkey, the blue sea was polluted with waste oil, the palms bore sooty dates among sooty fronds. And yet the pumps were a triumph, a glory of power.

Mark had a hankering to inspect them. One day, he decided, he would come over here and examine the works at his leisure. For the present... He looked inquiringly at Margaret. She pulled a face of distaste. He knew that she was seeing nothing beyond the dirt and destruction. She did not catch the feeling of strength and triumph over nature which lay behind it all.

'All right, we'll leave it now,' he said. 'We can go back again over the New Sea if you like—or we might keep round by the Mediterranean coast and have a look at Rome's old sparring partner, Carthage.'

Margaret shook her head at the alternative.

'The New Sea, I think. This place has shocked me, and one shock is enough for the day. If they've treated Carthage anything like they've treated Qabes, then delenda est Carthago indeed.'

Mark circled the plane and set off back over the pipelines. He held the same course until the sea was reached, when he altered a few points to the south of their outward journey. They drew clear of the old borders of the Shott el Jerid and found the newly inundated land where numerous islets varying in nature and extent from a few square yards of sand to well-planted groves of trees still survived. They descended until they were scudding a bare hundred feet above the water, able to look down on the strange sight of palms masquerading as marine growths.

'There's another village,' Margaret pointed out. 'But this one's breaking up: all the roofs have gone already, and some of the walls. I'm glad. It would be too eerie to think of fish making their homes where people once lived, swimming along the streets, and in and out of the windows and doors____'

Mark laughed. The notion struck him as delightfully absurd. He had started to reply when a sudden tremendous explosion cut him short.

The Sun Bird careered wildly, flinging both of them out of their seats. For a moment she seemed to stand on her tail; then, slipping and twisting, she plunged towards the water____

CHAPTER II

Mark opened his eyes and shut them again quickly. The glare of a brilliant shaft of sunshine through the window felt like a white hot wire in his head. The pulsing aches inside it magnified themselves a hundred times. After a short pause he wriggled slightly into the shadow and reopened his eyes more cautiously. This time he was successful in keeping them open. Shots of pain tore through his head, but, with the help of agonised facial contortions, it was possible to bear them. For an idle minute he lay regarding the roof of the Sun Bird uncomprehendingly until the memory of events jumped back at him. He shrugged to a sitting position and held his head in his hands. When the throbbing had eased a little he ventured to look round. The Sun Bird was on an even keel; a slight rise and fall told him that she was afloat.

'Margaret!' he called suddenly.

She lay crumpled beside him. The red curls spreading tangled on the floor hid her face. But there was an abandon about her whole pose which acted on him like a physical shock. He turned her over gently to find her face almost as white as the suit she wore. Its only colour was a little streak of blood trickling down her cheek from close by the right eye.

'Margaret!' he said again.

But she was breathing still. Her breast rose gently and evenly as though she slept: the pulse was regular, if not very strong. 'Only a knockout, thank God,' he thought. He struggled to his feet and, with the help of the seat cushions, arranged her more comfortably. Then he crossed to the window and looked out.

A nice sort of mess they were in. Something pretty final must have happened to the bunch of rocket tubes at the tail—and that meant the end of their motive power. There was no patching up to be done with rockets; either the system worked, or it was useless. It was lucky that there had been no pre-ignition—that would have meant nothing to show but a few scattered bits at the bottom of the New Sea. The Sun Bird's hull had of necessity been airtight for stratosphere travel, and it still appeared to be at least watertight—anyhow, there was no sign of leakage yet. Almost certainly one of the mixing chambers for the gases had burst, either through overcharging or on account of a flaw in the casting, and the explosion had carried away the whole group of exhaust tubes, together with both sets of rudders.

They were floating high, with the entrance well clear of the water. He unfastened the door and pushed it open with the intention of climbing out on the wing to survey the damage. But nothing of either wing remained, save a few twisted rods projecting a foot or more from the plane's smooth side. Both must have been torn clean away by the force with which they had met the water. By means of considerable scrambling and with a series of efforts which made the pulses in his brain throb and hammer, he managed to use the fragmentary wing supports as a means of scaling the curved side. At last, perched on the roof, he was able fully to realise the predicament.

The stripped fuselage was rolling gently as it drifted aimlessly upon the rippled surface, no more, now, than a helpless metal hulk looking like a huge, elongated metal eggshell. The sun was already well down in the sky, and with its decline a slight breeze had risen from the north. A number of islands and palm clumps were within sight. Mark silently thanked God that they had fallen clear of them. Directly to the south a palm grove of several acres still survived. It was a bare mile and a half away and the wind was urging him slowly towards it.

He prayed that the direction would not change. He would feel far safer with his feet on dry land, for though the hull appeared sound enough, only a careful examination could make certain. For all he could now tell there might be a gush of water from a weakened spot at any moment.

By leaning cautiously over the side he was able to see through the window that the girl had not moved. His hesitation whether he should go down and attempt to revive her was settled by a sudden freshening of the breeze. It was not impossible that they might pass right by the island while he was busy, and though sandy hummocks broke the surface in plenty, no other islet in sight was of such reassuring size and height. To add to his uncertainty the wind veered a few points west and it became a nice point whether they would not miss the island by a good margin. He watched the narrowing space anxiously.

At a quarter of a mile it became certain that they would clear the most easterly spit by at least fifty yards. Mark decided to take a chance. It should be possible if he swam strongly to tow the wreck sufficiently to one side. He dropped overboard to find that the water came no higher than his armpits, for the islands were the remnants not of sudden hills, but of gradual undulations.

Towing the Sun Bird ashore proved a longer business than he had anticipated; a man three-quarters submerged has but little weight to give him purchase, and the task was made the harder by the fact that the Mediterranean water is Salter and therefore more buoyant than that of the oceans. But the work grew progressively easier as the ground shelved until at last there came the welcome sound of the metal bottom grating on the sand. A few minutes later he had carried Margaret ashore and laid her in the shade of a tree.

A damp rag cooled her face and wiped away the trickle of blood. Her eyelids opened at last unsteadily, as though unwillingly, and the hazel eyes looked up into his. The arched brows straightened into hard lines and came together with deep creases between. Mark, with a sympathetic memory of his own blinding headache, offered a flask of brandy.

'Take some of this; it'll do you good.'

She drank without protest and closed her eyes once more. After a few minutes she looked at him again.

'I feel a bit better now. Let me sit up.' 'Certainly not. You lie here a bit longer. You've had a nasty bump.'

'What happened?' she asked.

Mark explained as far as he was able.

'If I hadn't been such a fool as to forget about the safety belts we should have been all right,' he added. 'As it is, I don't see why we haven't bust our skulls—I deserve to have done.'

'What are we going to do?'

'I don't know yet. We shall have to stay here for the night, anyhow. It'll be dark in half an hour. Tomorrow we'll see what can be managed. It depends mostly on the condition of the Sun Bird—poor old bus, that's a bit of a misnomer now: she'll certainly never fly again.' He looked regretfully at the silver hull gleaming in the last rays of the sun. 'There's a little tinned food and a small tank of water inside, so we needn't starve.' He looked back at her face a little anxiously. 'How are you feeling now?'

'Heaps better. Let me sit up.'

He was still uncertain how his news of the situation was being received.

'I'm damned sorry about all this-' he began.

She stopped him. 'My dear, you couldn't help it—and even if you could, I'm scarcely in a position to walk home.'

She was silent for some moments and he saw with surprise the beginning of a smile. He had been prepared for blame, reproaches, irritation, even calm acceptance of the situation—for anything, in fact, except a smile.

'Do you know,' she said, 'we've made a record?'

'What do you mean?'

'Well, nobody else has ever before achieved a shipwreck in the middle of the Sahara desert.'

Mark smiled too, and his spirits rose astonishingly.

'Come to that,' he said, 'I shouldn't think any girl was ever before kissed on a Saharan island.'

Mark suffered an uncomfortable dream. He had become, it appeared, a recumbent statue of himself, and was being dusted. A giant maidservant had removed her huge wig of red hair and was using it to whisk his face. She put one hand upon his stone chest for support, and leaned forward to reach the better. The hair irritated his nostrils abominably...

He woke suddenly. There was still a weight upon his chest, and something was still whisking back and forth across his nose. He sneezed abruptly and sat up, sending a dark form tumbling to the sand. There was a slight scutter before it collected its dignity and became a motionless black shadow in the moonlight. It gave a forth a faintly protesting mew. Mark looked at it unkindly.

'Blast you, cat,' he said, severely.

To a cat more used to kicks than words, this appeared a term of endearment. It approached and rubbed its head in a friendly way against his hand.

The New Sea was glittering with a hard beauty under the moon. A steely path of light stretched before him to the horizon over water which was scarcely rippled. A breeze, so light as hardly to be felt, caused the palm fronds above him to move with a papery rustling. He turned his head and saw with relief that the hulk of the Sun Bird still remained where he had left it.

A careful examination had proved it in better condition than he had hoped. The explosion had spent itself backward, ripping off the tail so smartly as to leave the main part of the fuselage intact. A few plates aft had been twisted open, revealing the sound-proofing material beneath, but in no part was there any sign of leakage. Reassured, he had insisted that Margaret should sleep on board. He contrived as comfortable a bed as possible for her, and, with the aid of severed control wires, he had improvised what he hoped were safe moorings. They seemed still to be holding.

He shivered slightly. The fire had dwindled to a few embers, and he leaned forward to build it up. Saharan nights can be chilly, and the fire served the double purpose of giving warmth and providing a signal.

There was no great likelihood of it being observed, but there remained always the possibility of a French observation plane cruising in this direction. They were used, he knew, to report progress and to effect salvage work upon occasion. The Government had frequently found it necessary to rescue diehards whom not even the threat of inundation had been able to persuade from their ancestral villages until the last moment. Among many of the Arabs understanding continued to fight with conviction. The French proposals were intelligible enough, but not a reality. Most of them felt that the desert always had been, and always would be; it was eternal. Not until the water crept to their very doors were they convinced. Only then did a howl go up demanding rescue either by Allah or the French Government. There had been a time when all the flying boats of both France and Italy had been pressed into refugee work, but, by now, the evacuation of most of the affected parts was complete.

With his head tilted back, Mark listened for the drone of an engine, but nothing broke the silence save the quiet stir of the sea and a faint swishing of the palm leaves. He wriggled nearer to the fire and pulled the coats which were doing rug duty more closely about him. Gazing at the revived flames he fell to considering the general cussedness of things. That the first time the Sun Bird had let him down, it should have chosen to do it in this no-man's-land. ...

Still, they had been lucky. If that explosion had occurred over dry land—or even at a good height above the water—it would have meant flowers for two. He thought of a number of well-pointed, nicely tempered phrases which he would joyfully plunge into the makers of 'Strato-planes' when he got home—not that it would do much good, but he would like them to hear just what he thought of them.

And then there was the radio____Two reputedly unbreakable valves thoroughly broken, and the whole installation useless just when it was most needed....

The cat interrupted him by brushing past his face and making her way beneath his covering. She curled up comfortably and began to purr like a miniature massage machine.

'Oh, all right, if you insist,' he told her sleepily, 'but if you get overlayed, don't blame me.'

'Hi,' a voice was saying, 'what about breakfast?'

His eyes opened to the sight of Margaret bending over him. He struggled into a sitting position and blinked at a sun which had evidently been up for some time, then he transferred his gaze back to the girl. She had contrived to make herself scarcely less neat and fresh than she had been at the start.

'How do you do it?' he asked, feeling his own bristling chin.

She laughed. 'A bathe and a comb—but I do wish I'd brought a toothbrush.'

'How's the head?'

She shook it, spinning her hair out in the sunlight like a copper-gold halo.

'No sign of an ache—though there's still a bump like an egg. A sleep and a swim do wonders.'

The cat emerged. It took a firm stand with its forepaws, extended its hind legs so far that its loins almost touched the ground, and yawned immoderately. Seen by daylight, it was not a very attractive specimen of its kind. The surprising prominence of its eyes and the faded quality of its gingery coat were the two most noticeable characteristics.

'Where on earth did you find that?' Margaret asked.

'I didn't; it found me. Planted itself on me—literally.'

'Puss—puss,' Margaret encouraged.

The cat regarded her for a solemn moment. It decided to wash its face.

'There's ingratitude for you,' said Mark. 'There's nothing more egocentric than a cat.'

'Poor thing. They left it behind, and it might have been drowned. Let's adopt it.'

'If you like—but cats can wait. Let's see about some food. I'm feeling half-starved.'

The Sun Bird's lockers supplied a number of brilliantly labelled tins.

'Grape fruit, tongue, some dates from the trees—oh, we won't do so badly. But I do wish we'd got some coffee— even the French idea of coffee wouldn't be too bad now. I hate tea for breakfast.'

Nevertheless, it was with a comfortable sense of repletion that they leaned back, enjoying cigarettes after the meal. Margaret watched the cat greedily consuming condensed milk.

'I think we'll call her Bast.'

'Why Bast?'

'You remember. The cat-headed goddess of the Egyptians—why, she may be a descendant of one of the actual cats they used to worship.'

'Highly probable. She has the manner—others might call it nerve. Henceforth, Bast she is.'

Margaret drew at her cigarette and changed the subject.

'What are we going to do? Just wait here?'

'I've been wondering about that,' Mark frowned. 'A patrol is bound to come along sooner or later—but the trouble is that we can't stay here for very long.'

'The sea?'

'Oh no. That's all right. The level rises so slowly that it won't flood this place for weeks, perhaps for months. No. I was thinking of the supply problem. We've got a little food, and there are the dates—though we'd soon get mighty sick of them—but the real trouble is drinking water. We've only got enough of that to last us two or three days. It really boils down to taking one risk or another. Either we stay here and chance their finding us before the water gives out, or else we try putting to sea in the poor old Sun Bird.'

'Putting to sea?'

'Don't look so surprised. She's perfectly watertight. I'm not proposing to be like the people who "went to sea in a sieve, they did"; not my idea of amusement, at all. We ought to be able to rig a sail of some kind. With that, and a means of steering, it would only be a matter of going right ahead till we find the shore. The sea's not really very big yet.'

Margaret looked uncertain.

'But suppose we land where there's nothing but desert?'

'I know. That's the real risk of the thing. The Sun Bird will be safe enough, but we may have to tramp over miles of sand at the end of the trip. What do you think?'

'Well, it's for you to decide, but if the Sun Bird is all right, it will be better to be doing something than just sitting and waiting, won't it? Besides, if a plane does happen to come along, it'll be more likely to see us out in the open than here.'

'You're right.' Mark scrambled to his feet and held out a hand to her. 'Let's go down to the old bus and see what's to do about it. Come on, Bast, you too.'

It proved less difficult than he had anticipated to improvise a sail from a rug. True, it was so heavy that half a gale would be necessary to make it belly out, but it served its purpose by getting in the way of what wind there was. Progress with its help would be slow, but moderately sure. A plank and other bits of jetsam from the island strand could be adapted for use as a rudder.

Mark, looking back at his handiwork from the shore whither he had waded to collect a final supply of dates, laughed aloud. Many an odd ship had sailed the seas, but few craft odder than the transformed Sun Bird. It was a very good thing she was safer than she looked. If she had been an ordinary plane, now—but in that case neither Margaret nor himself would have been alive....

'Come on, Bast, you're ship's cat from now on,' he said, picking her up and placing her upon his shoulder.

He gathered an armful of possessions and dates, and began to wade back.

The ex-control-wire mooring lines were hauled aboard; the ex-control-wire main-sheet shortened, and the good ship Sun Bird began slowly to move. Gradually she picked up, sliding reluctantly away from the shore.

'We're off,' said Margaret delightedly.

'Magnificent,' Mark agreed. 'We must be making almost a knot, and twice that in leeway. Just wait till we get clear of the island and can run before the wind. We'll show a turn of speed which would make snails blink.'

The two sat aft, perching none too steadily upon the polished, curving surface of the fuselage. Bast, unable to find any foothold save on the very crown, had been banished to the cabin for her own safety.

'It's lucky,' said Mark, 'that neither of us has any devoted relatives waiting for us at the Hotel de l'Etoile— they'd be getting a bit restive by now, and at this rate we mayn't be home for weeks.'

Margaret looked up from her occupation of making a sunshade out of an old newspaper, and nodded.

'They certainly would. As it is, I suppose nobody's taking any interest except the manager who'll want his money, and a few romantic people who are now spreading a report that we've eloped or that you've abducted me.'

Some two hours later Mark sat alone at the helm. Margaret was below, contriving a meal. The lightest of breezes continued to move the Sun Bird, though at a distressing dawdle. Only the gentlest ripples troubled the surface of the water; their faint clopping against the bows and Margaret's voice raised in expostulation were the only sounds.

'Really, Bast.' she was saying, 'you're not quite a lady, are you. And on the very best cushion, too. I'm ashamed of you. If you dare to-'

A sudden noise occurred astern. A thud, a roar of falling water, followed by a great splashing. Mark looked behind him. He was just in time to see the spray from the impact of two waves falling back upon foaming froth. There were a few moments of uncertain agitation, and then the troubled water began to swirl. From its slow first turns it began to speed up until it dipped conically at the centre. The froth disappeared. The water circled yet faster, the sides of the deepening cone looking hard, like dark glass.

He put the tiller hard over in an effort to keep clear of the whirlpool, but its influence was extending. Already he could feel the drag of it, and the wind was too light to hold against it. The Sun Bird rocked, seemed for a second to hesitate and then gave up. Reluctantly she answered to the pull of the water and began to drift astern. A sudden terrifying roar broke out. Margaret's head appeared through the doorway.

'What-?' she began.

'Look out!' Mark shouted. 'I'm coming down.'

He slid swiftly down the side of the hull, swung himself through the opening and slammed the door behind him.

'What was it? It sounded like all the baths in creation running out at once.'

'Look there!' He pointed through the window, and together they peered out.

The Sun Bird was beginning to travel fast, close to the edge of the whirlpool. They could look right down into the hollow of spinning water.

'The bottom must have given way. Caves or something like that below.'

'Do you think-?'

'Can't say. There may be enough force to drag us down. Perhaps we'll just spin in the middle till it fills up.'

He drew her back from the window. She turned very wide eyes to stare into his.

'Oh, Mark, if-'

'Come on. We've got to strap ourselves into our seats. There'll be a hell of a mix-up in here if we do go down. Quick now.'

They both slid hastily into their seats and fumbled for the buckles of the broad webbing belts. The Sun Bird was circling the wall of water at a prodigious pace. She tore spirally down it to spin like a top at the centre. Mark hoped desperately. Would she ...? Would she...?

She canted. The water rose dark over the windows. She swung abruptly, nose down. There was sudden, complete darkness inside. A sense of weightless dropping. Down and down____

CHAPTER III

A watch would have told that the Sun Bird did not fall for many seconds—but seconds, infinitely drawn, mean nothing. She fell for an eternity. Uncannily like those dreams of Mark's childhood when he had slid faster and faster down a stair-rail which had neither beginning nor end. There was the same sense of plunging weightlessness; the same awful apprehension of the end.

But the end when it did come was, like so many ends, an anticlimax. There was a back pull as though brakes of unthinkable power had been applied to the full. The webbing safety belts were put to a strain which crushed the breath from their wearers' bodies. Mark could hear himself giving out involuntary, uncouth grunts. For a moment he feared that the belt might give and send him hurtling forward against the window, to smash or to be smashed. But the fabric held and the pressure swiftly eased. Presently he could draw a needed breath. Then abruptly the force reversed and they were thrust deep into their seats. 'Coming up again,' he told himself. The Sun Bird, carried to the depths by the fall, was rising bubble-like.

She broke the surface, spun like an ill-balanced top and was carried away broadside. He sat up and prepared to loosen the belt, but even as his fingers reached the buckle there came a thunder of water on the roof, loud despite the sound-proofing. The craft rolled like a floating barrel and sank again; rose again, and drifted back once more beneath the falls. She spun, twisted, rose and fell, like a wood chip beneath a weir. The brains of the two within swirled giddily.

'Nothing to do but hope,' Mark told himself. 'Bound to float free sooner or later____My God, to think that they pay for things like this at fun-fairs.... Hope I'm not going to be ill.'

At last came a bump and a slight grating along one side. They could feel a slow, deliberate swinging. Mark waited for a moment, then:

'We're out of it,' he cried, unbuckling the strap. 'Where's that light switch?'

The small ceiling bulb revealed Margaret's slight form still sunk in the seat. She made a feeble attempt to smile at him.

'But I do feel sick,' she said plaintively.

'I'll bet you do. Just wait a minute while I find that flask.'

Bast emerged from the safe hiding of some corner, and stood looking at them from bemused, greenish-yellow eyes. She gave an unhappy mew and advanced towards Margaret. How she had contrived to remain undamaged was an unsolvable feline mystery.

The brandy which Mark at length produced had an immediate effect, not only of settling, but of heartening. Margaret loosed her safety belt and stood up. She staggered slightly.

'The ill treatment, not the drink,' she explained. 'Where are we? It's all dark outside.'

'Heaven only knows,' Mark managed, with an effect of lightness. 'A cave I should think, but it's a mighty big one to take a fall like that.' He pushed over a switch. 'Damn, the headlight's not working. Now where the devil did I stow those spare bulbs?'

He was convinced in his own mind that the end was not far off. The water from above would plunge down until the cave was filled. The Sun Bird would rise until she met the roof and could rise no more. The water would close round her, trapping them helplessly. The air in the storage cylinders would last them a few hours, and then ...

'Ah, got 'em,' he said.

They were being rocked jerkily; swinging in a way which suggested that thev were caught in a current, but the darkness outside was too intense to give even a hint of their surroundings. He crossed the cabin and opened the back of the headlight set above the front windows.

'Now,' he said, snapping it shut again with the new bulb in place, 'we'll be able to see just what we've fallen into.'

A brilliant beam slashed into the blackness. About them was swiftly flowing water, bearing them along. A few yards to the left was a rock-wall passing with surprising swiftness. Mark switched the light ahead, but there was little to be seen save the water swirling beside the rock until it disappeared into obscurity. To the right also the water stretched out beyond the lamp's range. Far above thern the upsweeping curve of a rocky roof could be dimly seen.

Mark's spirits rose. At least, catastrophe seemed less imminent.

'Well, well, here we are. But where we are, and where we're going, the Lord alone knows,' he said.

He turned to look at the girl and his temporary spurt of lightness vanished. She caught sight of his expression and slipped her arm in his.

'Never mind, dear. It's not your fault. You couldn't know that the Sun Bird was going to misbehave like that, nor that this was going to happen. Besides we're both— well, we're in it together, aren't we?'

He looked down at her standing beside him. The white suit was sadly crumpled, a small, yellow bruise showed close to her right eye, the soft hair was a tangled, dark red disorder shot with gold lights, and the hazel eyes gazed steadily back at his own. He kissed her.

'You're lovely. And you're a brick,' he said.

A long time—or what seemed a long time—later, the right-hand wall of the cavern came dimly into view, converging rapidly to form a rocky tunnel ahead. Clearly this vast underground lake was narrowing to its exit. Mark focused the light forward, and viewed the prospect with no little misgiving. The speed of the water was perceptibly increased and the surface was broken by swirls and wavelets; it was impossible to tell how deep lay the rocks which must cause them. He wondered uneasily how long their luck would hold. One rocky spike could, at their present speed, rip the bottom from stem to stern. And to what were these rapids the prelude? Another fall would be likely to dash them to pieces. It had been mere luck that the earlier drop ended in a deep pool. Suppose a pile of rocks had lain beneath ...?

The same thought was in Margaret's mind as she gazed frowningly forward; nevertheless, she managed to put some lightness into her tone as she spoke:

'I hope to goodness it's not another fall—I'm still feeling a bit sick from the last. I always thought that the people who go over Niagara in barrels were fools; now I know it.'

Mark drew her back from the windows.

'Better be on the safe side,' he said, pointing towards the seats.

The walls of the cavern closed in to leave a channel sixty or seventy feet wide. The Sun Bird was swept helplessly towards it, swinging and bobbing like a cork. Both held their breath as the course narrowed. It seemed impossible that they could safely clear the jutting spur at the left of the entrance. The stream gripped them, thrusting forward as if it could know no greater joy than to crush this metal eggshell upon sharp, savage rocks. Then, at the last moment, an outswirl of current deflected them. They were rushed past the spur with only a few inches to spare.

The searchlight had been left switched on, but it served only to heighten the effect of confusion. The beam flung erratically from side to side, confounding all sense of direction and giving every moment the impression that they were about to crash against one side or the other. Half a dozen times ominous scrapes on bottom or sides set their hearts pounding. One jolt after another convinced Mark that they were holed at last, but after each he was able to look round the cabin and see with relief that there was still no sign of leakage. It was a sharp cry from Margaret which managed, after twenty or more apprehensive minutes, to direct his attention farther ahead.

'Look!' she cried. 'Light!'

He stared through the forward windows. The motion made it difficult to be certain, but he seemed to catch a glimpse of a small patch of grey.

'Reflection,' he suggested.

'No, it's quite different. A colder, bluer kind of light than ours.'

He looked again, more carefully. The luminosity showed now in the shape of a high, almost Gothic, arch. 'As though,' he told himself, 'the end of this tunnel were silhouetted.' And its colour was, as Margaret had said, blue compared with the searchlight. Phosphorescence? But why should there be sudden phosphorescence? There was no trace of it in the water about them; a puzzle indeed, but soon to be solved, for their pace showed no sign of slackening.

He had to watch the opening grow larger and nearer for a longer time than he had expected. Distance in this darkness was deceptive, and his desire to be clear of the immediate dangers of the tunnel seemed to increase it. By the>time they swished out upon a second lake, he felt that miles had been covered. They left their seats when the former jerky progress subsided into a smooth gliding, and stood close against the windows. The silence of astonishment was broken by Margaret.

'It's impossible! I don't believe it.'

Mark, too, felt that the scene was more like a dream than a reality.

They were gazing across a lake which filled one of the largest caverns he had ever seen. So large was it that he looked apprehensively above; it seemed incredible that such a span of rock could be sustained without the help of pillars. But the size of the place, the acres of subterranean water accounted for only a small part of their astonishment. The phenomenon at which they stared open-mouthed was a system of lighting, beyond any doubt artificial.

At regular intervals about the roof were set globes which had the appearance of being frosted glass. From each came a glow of soft intensity, a light which was blue-white, yet not dazzling.

Mark's earlier anxiety was supplanted by a fresh nervousness. The lights had been erected for some purpose. But what purpose? And by whom? Hitherto they had faced natural, and roughly calculable dangers. All had depended on the Sun Bird's ability to survive; with her they had stood to live or perish. But with the discovery of the lights, a new element entered. They had been carried up against the unknown and, as always when all preconceived likelihoods are flouted, trepidation came crawling in. Men, he told himself, had put those lamps there—that could not be doubted. But what kind of men? What were men doing in these deep sunk caverns? Moreover, these glowing globes were unlike anything he had ever seen before—there was an entirely unfamiliar quality in the light they shed. As far as he could tell, they were a discovery not known above. What sort of reception might await intruders upon men who had for some reason hidden themselves deep and unsuspected in the earth? He glanced at Margaret, troubled. She was no longer gazing at the lamps; her attention had turned to the walls.

'Look, Mark,' she said, 'caves, there, above the water-line.'

He followed her pointing finger to see several openings, some near the water, others high in the wall, close to the roof. Moreover, he caught a detail which had escaped her. From the mouth of the largest a line of shadow ran slanting down into the water. A casual glance suggested a crack in the rock face; a longer look abolished the notion that it could be accidental.

'It's a ramp,' he said. 'A path leading up to that cave....'

For a few seconds he hesitated. They were drifting slowly now, and their course would take them not far from the wall. A disinclination to leave the comparative safety of the Sun Bird fought with the idea of a possible way back to the surface. To stay on board meant that they would allow themselves to drift farther and deeper into this maze of caverns. Already an unknown number of hundreds of feet lay between them and the daylight, and there was no guarantee that the exit from this lake would not take them over another fall. On the other hand, who—or what—might they encounter in the caves?

It was a choice of unknowns, but with the balance slightly in favour of exploration. After all, they could moor the Sun Bird, and have her ready for retreat. If they were to go on, there might be no other chance of landing. He pulled off his coat, and sat down to loosen his shoes, giving instructions to Margaret as he tugged at the laces.

'I'm going to swim over to that ramp. I want you to get on top and throw me a line when you're near enough. The control wires we used for mooring should be long enough if you join them. Think you can manage?'

She nodded, and started to search for the wires. Mark opened the door and dived out without hesitation, within ten minutes the manoeuvre had been accomplished. Mark had caught the curling wire, and the Sun Bird's metal belly was grating noisily as he pulled her bows on to the ramp. Margaret sprang down and stood beside him, watching him make fast.

'Isn't it quiet?' she said unhappily. 'I didn't think anywhere could be so horribly silent.'

Though she spoke in a low voice, the echoes managed to catch it and fling it eerily back and forth until it was no longer her voice, but a wandering, elemental sound. She shivered a little.

'I don't know which is worse; the silence, or the echoes.'

They listened for a moment to nothing. The silence sang in their ears with only an occasional clop-clopping of ripples to break it.

'Well,' said Mark cheerfully, 'as long as there's nothing but silence we needn't be afraid.'

The travesty which the jeering, booming echoes made of his statement seriously dismayed both of them. They glanced nervously at one another. Margaret took his arm, 'Do you really think we can get out that way?' she asked, looking up the ramp.

'Of course,' he managed with more conviction than he felt. 'The air's fresh here. There must be some way for it to circulate. If we can only-'

The rest of his sentence was drowned. There came the rumbling of a mighty crash, thunderous in the closed space. The solid rock beneath their feet trembled. Mighty reverberations like great breakers of sound buffeted back and forth across the cavern lake. A hundred yards along the wall a poised mass of rock detached itself and fell deafeningly into the water. Margaret's grip tightened on his arm. He could see her mouth forming inaudible words.

'Look!' he shouted, pointing back at the tunnel through which they had come.

A sudden wave of frothing water came charging out to spend itself upon the broader surface of the lake.

'The roof must have dropped in. We were just in time: there's no going back that way.'

Margaret's alarm abated as the echoes became more feeble. She made an attempt to meet the latest calamity with lightness.

'Never mind, my dear. There never was. Only salmon can climb waterfalls.'

CHAPTER IV

'Now, have we got everything?' Mark said thoughtfully.

He looked in a calculating manner at the bundle beside him, and began to tick off the items on his fingers.

'Food, bottles of water, flashlights, string, matches, knife____Lord, I nearly forgot...'

He slid from his seat and went to rummage in a locker. Margaret sat where she was, watching him extract a small pistol and drop it, along with a number of cartridge clips, into his pocket.

'Why?' she asked.

He shrugged his shoulders. 'I don't suppose we'll want it, but—well, it's better to have a pistol you don't want, than to want a pistol you've not got. We may run across— er—savage tribes or something when we get out.'

Margaret shook her head. The last sentence had been particularly unconvincing.

'Mark, you're trying to hide something from me. What are you afraid of?'

'Nonsense. I'm not afraid of anything. What is there to be afraid of? I'm just being prepared, that's all—old boy scout motto.'

'Mark, don't be a fool. I don't in the least mind being protected, but I will not be treated as an idiot. What is it?'

He looked at her for a moment.

'Sorry,' he apologised. 'You're right, I was being a fool. I won't play at he-men any more. Quite frankly I don't know what to expect. It's all so queer. First the lights, obviously put here for a purpose—but for what purpose? And then this ramp which may have been partly natural, but has certainly been finished off by hand—and not in a day or two, either. Whoever did it has kept it a good secret from the people above. It's ten to one that they— er—well, that they probably want to keep it a secret.'

'They may kill us, you mean?'

'I can't possibly say—that's why I'm being prepared.'

"But, Mark, who can they be? Surely there would be some rumour or suspicion?'

'That's the queerest part of the whole thing. I never heard of mining operations or anything of the sort in these parts, did you?'

'Perhaps the French Government--?'

'I shouldn't think so—anyhow, we'll find out sooner or later. Let's get out now.'-

They climbed from the Sun Bird, and he made to shut the door.

'No, wait a minute. We've forgotten-'

Margaret dashed back inside and reappeared with a wriggling bundle of fur.

'Poor Bast,' she said. 'We nearly left her to a dreadful fate. She'll have to come along with us.'

The cat mewed. Mark gave it a look of mild disapproval. It would probably be a damned nuisance; however, one could scarcely leave it to starve.

'Come on,' he said.

The ramp, an inclined ledge running along the face of the wall, was steep, but of no great length. A few minutes climbing was sufficient to bring them to its levelled off end in front of the cave mouth, and to show them a long tunnel illuminated at intervals by lamps similar to those over the water. Mark lingered only to cast down one regretful glance on the Sun Bird where she lay, glittering like a silver shuttle, at the water's edge. Then they turned their backs on the lake and entered the tunnel together.

For a time they walked in silence, each busy with thoughts. The floor had been smoothed and was dry, which made for easy progress. Both made efforts to convince themselves that it had an upward trend, but they were bound to admit that so slight a gradient would mean that many days walking lay between them and the surface. The monotonously echoed trudge of their feet began to get on Margaret's nerves. She glanced at the severely thoughtful expression on Mark's face.

'Well, what are you making of it?' she asked at length.

He started out of his reverie.

'Not much,' he admitted. 'I'm puzzled by that lake. Why on earth should anybody want to illuminate a lake? There weren't even any boats on it.'

They may have been washed away.'

'But there would have been mooring rings or something to show that they'd been there.' He shook his head. 'And that ramp.... It didn't stop just below the surface; it went on and down, a long way. I wonder if-?'

'What?'

'Well, perhaps it has only just become a lake—it's more easy to understand that a huge, dry cavern should be lit like that. Suppose that the water from above has only recently broken through and flooded it?'

'Yes, that might be possible—I wonder--?'

They tramped on for a time without speaking. Mark's mind returned to the problem of the inhabitants. Where were they? And what manner of people could they be? Neither the corridor nor the lake had been lighted without purpose; yet there was no sign nor sound of a creature other than themselves. Their entire absence was becoming more uncanny.

The tunnel began to turn to the left. He consulted a pocket compass and learnt that they were travelling north. It could scarcely be called a useful discovery, but he was glad to know it; the tunnel must communicate with others, and the compass would at least serve to prevent them travelling in circles. It was not long before they came to a choice of ways; a tunnel, exactly similar to the one they were in, cut across at right angles.

'Toss up for it,' suggested Margaret.

Mark, after a careful inspection, came to the conclusion that hers was as good a way of choosing as any other.

'Heads, we go forward; tails, we turn.'

The coin spun and fell to the ground with a tinkle.

'Heads it is,' cried Margaret, looking down at the profile of Queen Elizabeth the Second. The way beyond the crossing differed from their earlier tunnel only in having a slight breeze which blew in their faces and grew perceptibly cooler as they advanced. It carried, moreover, the tang of some faintly familiar, though unplaceable, odour. They hastened their steps at the suspicion that the monotony of bare tunnels was soon to be broken. Keeping straight ahead, disregarding the smaller side tunnels which now became more frequent, they made for the source of the draught. The air became still damper and fresher. It carried a suggestion of growing plants. Nevertheless, the sight which met them when they turned the final corner took them by surprise.

As if by common consent they stopped on the threshold of a great cavern, staring in speechless amazement. At last:

'Mushrooms!' said Margaret, feebly.

Far, far up in the roof the familiar globes were shedding their soft rays, but this time they fell on to neither barren rock nor water; they served to show a nightmare picture. From a bed of dark, soft loam which covered the ground grew a huge crop of queer forms. Most massive, and most noticeable were mushrooms. Monstrous mushrooms which balanced umbrellaed heads larger than wagon wheels upon thick, white trunks, eight or nine feet high. Taller still reached the sleek cones of more slender fungi, yellow, red, or steely grey. Closer to the ground, among the pillar-like mushroom columns grew great globular plants, some brick red, some dappled brown and cream, some white, like familiar puff-balls, giantly inflated. Varie-hued tendrils, fat, like gorged serpents, lay here and there, contorted and looped by their efforts to find growing space. Shapes which, but for the virulence of their colouring, might have been marrows contrived to struggle for a compressed existence between the trunks and the swelling balls. There was chaos of line and form, but still worse of colour. The brushes of a distraught painter might have dabbed into the impossible scene the sudden splashes of purples, greens, reds, and yellows.

The sight of Mark's wide-mouthed astonishment made Margaret laugh.

'But it's incredible—fantastic,' he objected.

She nodded. 'Do you know what it reminds me of? Pictures in story books when I was a kid—only this technique's more modern. Enormous toadstools under which gnomes lived. There was one just like that in one book.' She indicated a particularly arrogant scarlet fungus, spotted with white. 'But I never thought I should see the real thing. Let's go nearer.'

They stepped from the firm rock border on to the loam, and examined the nearest mushroom curiously. Mark opened his knife and prodded it. It was quite soft. He sliced off a piece of the trunk and tasted it cautiously. The flavour was coarse, and the matter fibrous, nevertheless:

'It is mushroom, all right,' he admitted. 'If we can find anything to burn, we might make a fire and cook some.'

With Mark keeping a look out for a suitable specimen, they made their way farther along the edge of the weird forest.

'I suppose,' he said, 'that this is a kind of fungus farm, and that all these things are edible—but I'd rather not try them until we know for certain. I seem to have heard that you can eat lots of fungi if they're cooked the right way—the trouble is to know which is the right way.'

Margaret set the cat on the floor where it ran a little ahead of them, sniffing curiously at the thick stems

'The more I see of this place,' she said, half to herself, 'the less I like it. First, unknown forms of light, and now this unthinkable fungus garden. Surely if men were mining down here they would have provisions sent down to them. They wouldn't choose to grow this stuff for food. It's quite certain that these things aren't natural; they've been forced, or developed, or something. How is it they're only grown here when they might have been commercialised up above?'

Mark grunted. He had grown tired for the moment of puzzling, and felt in a mood to accept what fortune offered. Here, for the taking, was food which would reinforce their meagre supply. Presently he found what he sought. A great mushroom, standing detached from the rest, on the fringe of the bed. It was easy to undercut it by hacking out large, white, pithy chunks.

'Stand clear!' he warned.

The giant toppled over with a thud. The head broke off and rolled free. He followed it and began to cut off manageable sections. While he was stooping, Margaret came up behind him. Her voice sounded odd:

'Mark, I'm going mad, or something.—There's one of the gnomes!'

'What?'

He spun round and stared at her. She had picked up Bast and was holding her in one arm. The other hand was pointing to a fungus which looked not unlike a dingy yellow beach umbrella. Motionless in its shadow, the queerest figure he had ever seen stood watching them.

Against the phantasmagoria of growths it was impossible to make an estimate of the watcher's size. Mark could only be certain that he was considerably shorter than himself. The unclothed body was covered with a skin which was grey-white, like dirty vellum. So lacking was it in pigmentation that it could not have known sunlight for many years, if at all. All four limbs were thin, though without emaciation; a not ill-formed, slender body was surmounted by an unusually round head. Two large, black eyes were gazing steadily and unblinkingly: they gave to the slightly negroid features an expression of deep and permanent melancholy. There was something in the racial type which stirred Mark's memory faintly; somewhere, either in a picture, or in real life, he was sure that he had seen faces stamped with just such an expression of unending sadness.

'Look, there's another,' Margaret nodded a little to the right.

He saw another figure hitherto unnoticed and all but invisible, so like was its bleached skin to the colour of the fungus trunks.

'And another—and another. Dozens of them,' she added.

Mark began to grow nervous beneath the unwavering stares. How long had these creatures been there? He wondered. Were there more of them even now prowling closer through the fungus thickets? He could feel the impact of all those dark, mournful eyes, following every detail of his movements. He looked questioningly at Margaret, She shook her tangled curls.

'My dear, I don't know. They don't seem very dangerous, do they? Perhaps they're only interested....'

Mark thought. These queer folk must know the way to the surface—and they must be made to tell. They might intend no harm, but it would be better to make certain. He drew his pistol and assured himself that the magazine was full.

'We'd better get into the tunnel—it'll be less exposed,' he said, turning.

They had taken less than half a dozen steps when a rustle of movement came from among the fungi. An unseen signal put the white-grey men into simultaneous action. Mark, looking over his shoulder, was taken aback by their numbers; they showed in a score of unsuspected places, made visible now by movement.

'Run!' he cried.

A thudding of many bare feet sounded behind them, but they gained the tunnel mouth with a good lead. He stopped and faced round, putting Margaret behind him. The pistol was levelled threateningly; evidently it was known as a weapon, for they stopped short. He tried them in English.

'We want to get out. We want to go up,' he said, pointing to the roof.

The faces—nearly a hundred of them, he guessed—remained stolidly uncomprehending. He tried again. Pointing first to himself, and then again upwards.

'I—up,' he said hopefully, but the faces remained un-encouraging.

'Oh, damn!' He glared angrily at them. Now that they were clear of the growths it became easier to judge their size; the tallest of them he put at about four feet six, though several stood no more than four feet.

'Try them in French,' he suggested to Margaret.

She stepped from behind him, with the cat still held in her arms. The effect was immediate and astonishing. Before she could open her mouth the little men grew suddenly excited. As if they had abruptly come to life, a buzz of chatter arose. Gesticulating arms pointed at her, expressions became animated. She turned back to Mark, disconcerted.

'What on earth-?' she began.

'Look out.' He dragged her roughly back.

The little men came forward at a run. He pulled his trigger viciously, firing blind into the press of their bodies. There could be no missing. A number dropped, and the charge checked. Several injured were screaming with pain. The reverberation of the shots was still echoing back and forth across the great cavern. The mingled uproar was awesome and unnerving after the silence. The still forms on the ground looked pathetically like those of children. Mark felt slightly sick, but he continued to brandish his pistol cn the faces of the rest, waving them back. Margaret drew her breath with a sound which was half whimper. She forced her eyes from the fallen bodies and looked into his, horrified and part afraid.

'Oh, Mark, they're dead. You—you-'

He moved towards her and she shrunk back. The fear in her face was not of the little men.

'But, Margaret, I had to-'

'So suddenly,' she murmured. 'So horribly suddenly. A minute ago they were running, and now- Oh, Mark, what have you done?'

Mark turned away. He hadn't intended to kill—only to stop. It wasn't really himself who had pulled that trigger so vengefully; something had taken hold of him ... oh, damnation....

The men had drawn off. Their faces were expressionless once more, and their eyes watched enigmatically. Perhaps he had been too hasty. Perhaps, as Margaret seemed to think, they had meant no harm. But he couldn't afford to let them come to grips on a mere 'perhaps'. Besides, there had been an air of determination about that charge....

He thrust a new clip into his pistol without ceasing to watch. They had started talking again in their queer, staccato tones. For the most part, their attention seemed to be directed at Margaret, though occasional apprehensive glances were thrown at his pistol. A deploying movement began. The crowd was stringing out in a semicircle about the tunnel mouth. He felt that they were contemplating a new rush. It would be impossible to hold off a charge spread over a hundred and eighty degrees.

From farther up the passage he might be able to hold them. He began to retreat backwards, never removing his eyes from their faces. But they did not advance at once. He wondered uncomfortably what was going on behind those sad, yet inexpressive faces.

He was a good thirty yards from the entrance before they moved. He saw a sudden stiffening run through them, then they were rushing headlong. His pistol spat viciously. The lead tore holes in their line. The noise of his shots in the confined space was a crashing, deafening roar which made his head sing. He could hear nothing else; certainly he had no suspicion of a hundred naked feet pattering behind him.

One choked cry from Margaret was all his warning, and it came too late. He went down even as he turned, in a rush of grey-skinned bodies. His pistol flew from his hand. His flailing legs and arms were seized and pinned down. A weight of squirming bodies was crushing the air from his lungs. Small fists clenched themselves in his hair and began to hammer the back of his head against the floor. Sickening, splitting thuds. There was a pain behind .his eyes, hurting like the devil. His brain felt as though it were slopping about in its case like thin porridge....