FIVE years had passed since the Ithuriel had vanished like a cloud from the sky, leaving, so far as the air-ship itself was concerned, no more trace than if she had soared into space beyond the sphere of the earth’s attraction and departed to another planet.

All the rest of the winter of 2030-1, tidings had been sought most anxiously, but in vain, by the kindred and friends of those who had formed her crew during the ill-fated voyage on which she had disappeared into the unknown. The earth had been ransacked east and west, north and south, by the aerial fleet in search of the missing Ithuriel, but without result.

She had been traced to St. Petersburg and VorobiÈvo?, but there, like the phantom craft of the Flying Dutchman, she had melted into thin air so far as any result of the search could show. But when the snows thawed on the mountains of Norway, and the bodies of eight Aerians who had formed her crew on her last fatal voyage were discovered by a couple of foresters in a melting snowdrift on the very spot on which Vladimir Romanoff had been killed with his companions by order of the Supreme Council, a thrill both of horror and excitement ran through the whole civilised world.

That their death was intimately connected with the disappearance of the air-ship was instantly plain to everyone, and the only inference which could be drawn from such a conclusion was that at last some power, silent, mysterious, and intangible, had come into existence prepared to dispute the empire of the world with the Aerians, and, more than this, had already struck them a deadly blow which it was utterly beyond their power to return.

The effects of this discovery were exactly what Olga had anticipated. From the first time since their ancestors had conquered the earth and made war impossible, the supreme authority of the Aerians was called into question. It was quite beyond their power to conceal the fact that their flagship had either deserted or been captured, incredible as either alternative seemed. The Central Council therefore wisely accepted the situation, and immediately after the discovery of the bodies the President published a full account of her last voyage, as far as was known, in the columns of The European Review, the leading newspaper of the day in the Old World.

The only clue to the fate of the air-ship seemed to lie in the fact that at St. Petersburg a youth and young girl with whom Alan and Alexis had made friends on their journey from London had gone on board the Ithuriel for a trip to the clouds. But this led to nothing. Who was to recognise the daughter of the Tsar and the last male scion of the House of Romanoff in Olga and Serge Ivanitch, who had never been known as anything but the orphan grandchildren of Paul Ivanitch, the sculptor.

More than this, even to entertain for a moment the supposition that this boy and girl—for they were known to be little more—could by any possible means have overcome the ten Aerians, armed as they were with their terrible death-power, and then have vanished into space with the air-ship would have been to shatter the supremacy of the Aerians at a blow.

Even as it was, the wildest and most dangerous rumours began to fly from lip to lip and nation to nation all round the world, and for the first time since the days of the Terror the “Earth Folk” began to think of the Aerians rather as men like themselves than as the superior race which they had hitherto regarded them.

The President of Aeria at once issued a proclamation asking, in the interests of peace and public security, for the assistance of all the civilised peoples of the earth in his efforts to discover the lost air-ship, and also conditionally declaring a war of extermination on any Power or nation which either concealed the whereabouts of the Ithuriel or gave any assistance to those who might be in possession of her. This proclamation was published simultaneously in all the newspapers of the world, and produced a most profound sensation wherever it was read.

The terrible magic of the ominous word “war” roused at once the deathless spirit of combativeness that had lain dormant for all these years. It was impossible not to recognise the fact that this mysterious power, which had come unseen into existence and had snatched the finest vessel in the Aerian navy from the possession of the Council with such daring and skill that not a trace of her was to be found, could have but one object in view, and that was to dispute the Empire of the Air with the descendants of the Terrorists.

This could mean nothing else than the outbreak, sooner or later, of a strife that would be a veritable battle of the gods, a struggle which would shake the world and convulse human society throughout its whole extent. The general sense of peace and security in which men had lived for four generations was shattered at a stroke by the universal apprehension of the blow that all men felt to be inevitable, but which would be struck no man knew when or how.

A year passed, and nothing happened. The world went on its way in peace, the Aerian patrols circled the earth with a moving girdle of aerial cruisers, ready to give instantaneous warning of the first reappearance of the lost Ithuriel; but nothing was discovered. If she still existed, she was so skilfully concealed as to be practically beyond the reach of human search.

Then without the slightest warning, while Anglo-Saxondom was in the midst of the hundred and thirtieth celebration of the Festival of Deliverance, the civilised world was started out of the sense of security into which it had once more begun to fall by the publication, in The European Review, of the following piece of intelligence:—

A MYSTERY OF THE SEA.

Disappearance of Three Transports.

It is our duty to chronicle the astounding and disquieting fact that the three transports, Massilia, Ceres, and AstrÆa, belonging respectively to the Eastern, Southern, and Western Services, have disappeared.

The first left New York for Southampton four days ago, and should have arrived yesterday. The Central Atlantic signalling station reported her “All well” at midday on Tuesday, and this is the last news that has been heard of her. The second was reported from Cape Verd Station on her voyage from Cape Town to Marseilles, and there all trace of her is lost, as she never reached the Canary Station. The third was last heard of from Station No. 2 in the Indian Ocean, which is situated at the intersection of the 80th meridian of east longitude with the 20th parallel of south latitude; she was on her way from Melbourne to Alexandria, and should have touched at Aden two days ago.

The disappearance of these three magnificent vessels, filled as they were with passengers and loaded with cargoes of enormous value both in money and material, can only be described as a calamity of world-wide importance. Unhappily, too, the mystery which surrounds their fate invests it with a sinister aspect which it is impossible to ignore.

That their loss is the result of accident or shipwreck it is almost impossible to believe. They represented the latest triumphs of modern shipbuilding. All were over forty thousand tons in measurement, and had engines capable of driving them at a speed of fifty nautical miles an hour through the water.

For fifty years no ocean transport has suffered shipwreck or even serious injury, so completely has modern engineering skill triumphed over the now conquered elements. Added to this, no storms of even ordinary violence have occurred along their routes. After passing the stations at which they were last reported, they vanished, and that is all that is known about them.

The President of Aeria has desired us to state that he has ordered his submarine squadrons stationed at Zanzibar, Ascension, and Fayal, to explore the ocean beds along the routes pursued by the transports. Until we receive news of the result of their investigation it will be well to refrain from further comment on this mysterious misfortune which has suddenly and unexpectedly fallen upon the world, and in doing so we shall only express the fervent desire of all civilised men and women when we express the hope that this calamity, grievous as it is, may not be the precursor of even greater misfortunes to come.

It would be almost impossible for us of the present day to form any adequate estimate of the thrill of horror and consternation which this brief and temperately-worded narration of the mysterious loss of the three transports sent through the world of the twenty-first century. Not only was it the first event of the kind that had occurred within the memory of living men, but, saving the loss of the Ithuriel, it was the first dark cloud that had appeared in the clear heaven of peace and prosperity for more than a hundred and twenty years.

But terrible as was the state of excitement and anxiety into which it threw the nations of the world, it gave place to a still deeper horror and bewilderment when day after day passed and no tidings were received of the three submarine squadrons, consisting of three vessels each, which had been sent to inquire into the fate of the transports. They dived beneath the waves of the Indian Ocean and the Atlantic, and that was the last that was ever seen of them.

Month after month went by, every week bringing news of some fresh calamity at sea—of the disappearance of transport after transport along the great routes of ocean travel, of squadron after squadron of submarine cruisers which plunged into the abysses of the sea to discover and attack the mysterious enemy of mankind that lay hidden in the depths, and which never reappeared on the surface. Whether they were captured or destroyed it was impossible to say, simply because no member of their crews ever returned to tell the tale.

Whatever doubt there had been as to the existence or hostile nature of this ocean terror that was paralysing the trade of the world was speedily set at rest by a discovery made in the spring of the year 2032 by a party of divers who descended to repair a fault in one of the Atlantic cables about two hundred miles west of Ireland.

There, lying in the Atlantic ooze, they found the shattered fragments of the Sirius, a transport which had disappeared about a month before. The great hull of the splendid vessel had been torn asunder by some explosive of tremendous power, and, more than this, her hold had been rifled of all its treasure and the most valuable portions of its cargo. After this there no longer remained any doubt that the depths of the ocean were the hunting-ground of some foe of society, one at least of whose objects was plunder.

The President and Council of Aeria found themselves at last confronted and baffled by an enemy who could neither be seen nor reached in his hiding-place, wherever it might be, beneath the surface of the waters. Thousands of lives had been sacrificed, and treasure in millions had been lost by the end of the first year of what men had now come to call the New Terror.

New fleets of submarine cruisers were built and held in readiness in all the great ports of the world, and these scoured the ocean depths in all directions with no further result than the swift and silent annihilation of vessel after vessel by some power which struck irresistibly out of the darkness and then vanished the moment that the blow had been delivered.

As yet, however, no enemy appeared on land or in the air, nor were any tidings heard of the lost Ithuriel, or her captain and lieutenant. The Aerians had replaced her with ten almost identical vessels and had raised the strength of their navy to two hundred and fifty vessels, one hundred of which were kept in readiness in Aeria, while the other hundred and fifty were distributed in small squadrons at twenty-four stations, half of which were in the Western hemisphere and half in the Eastern.

The submarine warfare had now practically ceased. Nearly two hundred vessels belonging to Aeria, Britain, and America, had been captured or destroyed by an enemy which at the period at which this portion of the narrative opens was as supreme throughout the realm of the waters as the Aerians were in the air. To the menace of the air-ships this hidden foe replied by severing all the oceanic cables and paralysing the communication of the world save overland and through the air.

Thus, at the end of six years after the capture of the Ithuriel by Olga Romanoff more than half the work of those who had brought peace on earth after the Armageddon of 1904 had been undone. All over the world, not even excepting in Aeria, men lived in a state of constant anxiety and apprehension, not knowing where or how their invisible enemy would strike them next.

The Masters of the World were supreme no longer, for a new power had arisen which, within the limits of the seas, had proved itself stronger than they were. Communication between continent and continent had almost ceased, save where the Aerian air-ships were employed. In six short years the peace of the world had been destroyed and the stability of society shaken.

Among the nations of Anglo-Saxondom the change had manifested itself by a swift decadence into the worst forms of unbridled democracy. Men’s minds were unhinged, and the most extravagant opinions found acceptance.

Parliaments had already been made annual and were fast sinking into machines for registering the ever-changing opinions of rival factions and their leaders. Sovereigns and presidents were little better than popular puppets existing on sufferance. In short, all that Paul Romanoff had prophesied was coming to pass more rapidly than even he had expected so far as the area of the Anglo-Saxon Federation was concerned.

In the Moslem Empire affairs were different, but no less threatening. The Sultan Khalid the Magnificent, as he was justly styled by his admirers, saw clearly that the time must come when this mysterious enemy would emerge from the waters and attempt the conquest of the land, and for three years past he had been manufacturing weapons and forming armies against the day of battle which he considered inevitable, and which he longed for rather than dreaded.

Thus, while Anglo-Saxondom was lapsing into the anarchy of unrestrained democracy, the Moslem monarch was preparing to take advantage of the issue of events which, skilfully turned to account, might one day make him master of the world.

Such was the condition of affairs throughout the world on the 1st of May 2036, and then the long-expected came in strange and terrible shape. At midnight a blaze of light was seen far up in the sky over the city of Aeria. A moment later something that must have been a small block of metal fell from a tremendous height in the square in the centre of the city, and was shivered to fragments by the force of its fall.

On the splintered pavement where it fell was found a little roll of parchment addressed to the President. It was taken to him, and he opened it and read these words:—

To Alan Arnold, President of Aeria.

If you want your son Alan and his friend Alexis, go and look for them on an island which you will find near the intersection of the 40th parallel of south latitude and the 120th meridian of west longitude in the South Pacific. They have served my turn, and I have done with them. Perhaps they will be able to tell you how I have conquered the Empire of the Sea. Before long I shall have wrested the Empire of the Air from you as well.

Olga Romanoff.