So the truce was broken and the millions advanced, as it were over the brink of Eternity, towards London. But the reinforcements never came. Every transport that steamed out of Bremen, Hamburg, Kiel, Antwerp, Brest or Calais, vanished into the waters; for now the whole squadron of twelve Ithuriels had been launched and had got to work, and the British fleets from the Mediterranean, the China Seas and the North Atlantic, had once more asserted Britain's supremacy on the seas. In addition to these, ten first-class battleships, twelve first and fifteen second-class cruisers and fifty destroyers had been turned out by the Home yards, and so the British Islands were once more ringed with an unbreakable wall of steel. One invasion had been accomplished, but now no other was possible. The French Government absolutely refused to send any more men. The Italian armies had crossed the Alps at three points, and every soldier left in France was wanted to defend her own fortresses and cities from the attack of the invader.

But, despite all this, the War Lord held to his purpose; and that night the last battle ever fought between civilised nations began, and when the sun rose on the sixteenth of April, its rays lit up what was probably the most awful scene of carnage that human eyes had ever looked upon. The battle-line of the invaders had extended from Sheerness to Reading in a sort of irregular semicircle, and it was estimated afterwards that not less than a million and a half of killed and wounded men, fifty thousand horses and hundreds of disabled batteries of light and heavy artillery strewed the long line of defeat and conquest.

The British aërial fleet of twenty ships had made victory for the defenders a practical certainty. As Admiral Hingeston had told the Tsar, they could both out-fly and out-shoot the Flying Fishes. This they did and more. The moment that a battery got into position half a dozen searchlights were concentrated on it. Then came a hail of shells, and a series of explosions which smashed the guns to fragments and killed every living thing within a radius of a hundred yards. Infantry and cavalry shared the same fate the moment that any formation was made for an attack on the British positions; the storm of fire was made ten-fold more terrible by the unceasing bombardment from the air; and the brilliant glow of the searchlights thrown down from a height of a thousand feet or so along the lines of the attacking forces made the work of the defenders comparatively easy, for the man in a fight who can see and is not seen is worth several who are seen and yet fight in the dark.

But the assailants were exposed to an even more deadly danger than artillery or rifle fire. The catastrophe which had overwhelmed the British Fleet in Dover Harbour was repeated with ten-fold effect; but this time the tables were turned. The British aërial fleet hunted the Flying Fishes as hawks hunt partridges, and whenever one of them was found over a hostile position a shell from the silent, flameless guns hit her, and down she went to explode like a volcano amongst masses of cavalry, infantry and artillery, and of this utter panic was the only natural result.

Eleven out of the twelve Flying Fishes were thus accounted for. What had become of the twelfth no one knew. It might have been partially crippled and fallen far away from the great battlefield; or it might have turned tail and escaped, and in this case it was a practical certainty, at least in Lennard's mind, that it was John Castellan's own vessel and that he, seeing that the battle was lost, had taken her away to some unknown spot in order to fulfil the threat contained in his letter, and for this reason five of the British airships were at once despatched to mount guard over the great cannon at Bolton.

The defeat of the Allies both by land and sea, though accomplished at the eleventh hour of the world's threatened fate, had been so complete and crushing, and the death-total had reached such a ghastly figure, that Austria, Russia and France flatly refused to continue the Alliance. After all the tremendous sacrifice that had been made in men, money and material they had not even reached London. From their outposts on the Surrey hills they could see the vast city, silent and apparently sleeping under its canopy of hazy clouds, but that was all. It was still as distant from them as the poles; and so the Allies looked upon it and then upon their dead, and admitted, by their silence if not by their words, that Britain the Unconquered was unconquerable still.

The German Emperor's fit had passed. Even he was appalled when upon that memorable morning he received the joint note of his three Allies and learnt the awful cost of that one night's fighting.

Just as he was countersigning the Note of Capitulation in the headquarters at Aldershot, the Auriole swung round from the northward and descended on to the turf flying the flag of truce. He saw it through the window, got up, put his right hand on the butt of the revolver in his hip-pocket, thought hard for one fateful moment, then took it away and went out.

At the gate he met Lord Kitchener; they exchanged salutes and shook hands, and the Kaiser said: