Ober-leutnant von Loringhoven left his passenger severely alone. For one thing the commander's attention was almost entirely taken up with the work of navigating his cumbersome craft back to the Fatherland; for another he mistrusted spies, even when they were Germans and notwithstanding the fact that he himself had indulged in that dangerous pastime. But there was this difference. Von Loringhoven was a naval officer while von Eitelwurmer was a civilian. He had heard of German spies renouncing their allegiance and acting for the country in which they were to be working on behalf of the authorities at Berlin.
The spy had been accommodated with a camp-stool. On either side of the narrow compartment was a window fitted with double plate-glass windows. The for'ard bulkhead was pierced by a door leading to the cat-walk or suspended bridge communicating with both the 'midships and for'ard gondolas. Aft was another bulkhead separating a portion of the compartment from that containing the motors actuating the two rearmost propellers. The floor was in a state of continual tremor under the pulsations of the engines and the rattle of the two endless chains that transmitted the power to the two outboard propellers.
The limited space was still further taken up by two machine-guns mounted on aluminium alloy pedestals and capable of being trained through a fairly broad arc. By these stood four of the crew, ready at the first alarm to lower the glass panes and bring the weapons into action. The men were taciturn and obviously nervous. When flying over the unprotected towns and dropping their murderous cargoes they could be boisterous enough, but now, knowing that they had to run the gauntlet, they were feeling particularly cowed. The fear of being paid back in their own coin—a possibility that alone makes the Hun howl—gripped them, and held them in a state of prolonged mental torture.
Presently at an order communicated by telephone from the foremost gondola, the machine-gunners lowered the sashes of the windows. The temperature, already -2 °C. fell rapidly to -10 °C. Warm air-currents from the motor-room drifted through gaps in the partition and condensing fell upon the floor in the form of globules of ice.
Up and up climbed the Zeppelin. She was approaching the East Coast.
Von Eitelwurmer, overcoming his torpor, went to the window. One of the men was about to motion him to his seat, when another touched him on the shoulder and pointed.
Far below the whole country was in darkness. The spy could not tell whether it was land or water. Away to the southward a group of searchlights swept the sky, the beams impinging upon a bank of clouds that floated at a height of nearly a mile. Still further away more electric rays swayed slowly to and fro. At intervals the searchlights of the nearmost station crossed those of the one more remote, while in turn these effected a luminous exchange with rays still further away. As far as the eye could see there appeared to be a continuous barrage of light through which the returning raider must pass before gaining her base.
At an order the motors were switched off. Almost absolute silence succeeded the noisy roar of the seven 240-horse-power engines. The airship, at the mercy of the winds, began to turn broadside on to the aerial drift, yet the while, by means of ballast thrown overboard and the release of more compressed hydrogen from the cylinders into the ballonets, was steadily climbing.
It was von Loringhoven's aim to ascend until the Zeppelin was above the clouds. Screened from those dangerous searchlights the airship would then drift over the coast-line until such times as it would be deemed safe to restart the motors.
With the altitude gauge hovering at 4,000 metres the raider found herself just above the natural screen. The belt of clouds was not more than three hundred feet in height—sufficient to hide her from the earth, yet transparent enough to allow the rays of the searchlight to penetrate the vapour.
To the spy the outlook resembled the view from a railway carriage when dense clouds of steam waft past the windows. So powerful were the rays of the searchlights that the stratum of the vapour was flooded with silvery luminosity, while—ominous sign—the beams no longer swayed to and fro as previously, but hung with sinister persistence upon the bank of clouds with which the airship hoped to screen herself from observation.
Even as von Eitelwurmer looked a huge dark shadow eclipsed the concentrated beams. It was moving slowly at a rate hardly exceeding that of the airship. For that reason the object could not be an aeroplane. Perhaps it was some deadly invention that the English had brought into action against the Zeppelins—a sort of aerial torpedo steered by wireless electric waves?
The machine-gunners saw it too. The last atom of courage literally oozed out of their boots, yet almost automatically they gripped the handle that would liberate shots at the rate of 500 a minute if to the voidless night.
It was fortunate for them that they did not open fire. The shadow was that of another Zeppelin that at less than a hundred feet below was slowly forging ahead in a southerly direction under the action of her throttled-down motors, and with her exhausts carefully muffled.
In five minutes the novel Zeppelin eclipse was over, although at no time was the actual airship to be seen. She had previously been fired upon by the anti-aircraft guns on the coast and was now cautiously smelling her way through the clouds in order to find an undefended gap in the defences.
Another half-hour passed in acute suspense, Three times the anxious crew heard the terrifying sound of an aerial propeller. Somewhere in the darkness the British hornets were up and searching for their lurking foe—so far without success unless the moral effect be taken into consideration.
Presently the Zeppelin drifted beyond the glare of the fixed searchlights, but not until another twenty minutes had passed did von Loringhoven give orders for the engines to be restarted. At that terrific altitude the noise was considerably diminished in volume. Instead of the explosions of the motors resembling a succession of rifle-shots the sounds were like those of a whip being cracked, yet as the airship descended steadily to a height of five thousand feet the noise resumed its normal and distracting violence.
The spy sat down again. His torpor was returning. The sudden change of altitude had resulted in a steady flow of blood from his nose, while his ear-drums throbbed until they seemed on the point of bursting. At that moment he felt that he would not have minded had the airship been blown to atoms.
But the next instant his lassitude vanished, as the loud pop-pop-pop of two of her machine-guns roused him from his stupor. The weapon on the starboard side was trained as far as possible abaft the beam and was pumping out nickel into the darkness.
Craning his neck over the shoulders of the men serving the belt-ammunition von Eitelwurmer saw a sight that caused his agonies of mind to return with redoubled violence.
Just visible against the loom of the starlit sky was a huge biplane that, climbing steeply, seemed to be steadily overhauling the airship. Serenely unmindful of the hail of bullets aimed at her the seaplane held on with the obvious intention of getting astride her prey.
Mingled with the detonations of the machine-guns were the clanging of telephone bells, the clank of machinery and the excited voices of the crew. Then with a jerk that threw the spy violently against the after bulkhead the Zeppelin leapt skywards. Simultaneously dense volumes of black smoke eddied in through the open windows.
Sprawling in the intense darkness upon the ice-encrusted floor of the gondola the spy vainly strove to shriek, but only a gurgled sound came from his lips. He had not the slightest doubt but that the airship was on fire and on the point of crashing to her doom.
Hearing the stifled cry, for again the motors were stopped, one of the crew gripped him roughly by the arm, and set him on his feet.