No one knew when or how the first assault would be delivered. All that was known was that, unless Olga and her advisers had completely altered their plans, the attack would take place either that day or the next, and consequently ceaseless vigilance was necessary on sea and land and in the air.
In accordance with the plan arranged on board the Narwhal, ten air-ships rose above the clouds to an altitude of five thousand feet, and from each of these an electric thread hung down to as many signal-stations on the island, all of which were connected with the headquarters at the top of Christmas Harbour.
Twenty cruisers patrolled the coast at a distance of a mile from the land, and two miles outside these the Narwhal ran to and fro along the northern shore. All the more important inlets which had sufficient depth of water for submarine attack were guarded with mines and chains of torpedoes, so disposed that no vessel could possibly enter without firing them, and so giving warning of the locality of the attack.
The afternoon passed without any alarm, and at nightfall the clouds sent down a blinding storm of snow, which, added to the intense darkness, made vision impossible both on land and sea, although high above the clouds the ten air-ships floated in a calm, clear atmosphere, under the brilliant constellations of the southern hemisphere.
No attack seemed possible without warning, either by sea or above the clouds, for the hostile air-ships could not approach without being seen from a great distance through the clear, starlit sky, and without their lights, which would instantly betray their presence, it was impossible for the submarine vessels even to find the coast.
Hour after hour passed, and still no hostile sign rewarded the vigilance of the defenders. No one of the present day could have guessed that all the preparations had been made for such a battle as had never been fought before on sea or land, or in the air.
Nothing was visible but the snow-covered earth and the storm-swept sea, for the sentinel ships, floating far above the clouds, were beyond the reach of vision. And yet, if the combined fleets of the modern world had attacked Kerguelen that night, not a ship would have escaped to tell the tale of annihilation, so terrible were the engines of destruction which waited but the signal of battle to strike their swift and irresistible blows.
It was about half-past six o’clock the next morning when Alexis, who was on watch in the conning-tower of the Narwhal, saw a faint beam of light illuminating the water a long way ahead. He instantly signalled to Alan—“Enemy in sight. Back. I am going to ram.”
Alan, unwilling to leave the new crew, who were not yet perfectly acquainted with the working of the machinery, had taken command of the engine-room alternately with Alexis, who was now taking his four hours’ watch in the conning-tower, and to whom the fortune of war had given the honour of striking the first blow. The Narwhal backed rapidly, and as she did so Alexis turned a small wheel in the side of the conning-tower, and the whole chamber sank into the hull of the vessel.