"Accidentally I found some incriminating writing. He saw what I had done and let rip at me with a revolver. Needless to say he missed."

"That's the third lucky escape you've had from his murderous intentions," remarked Entwistle quietly. "I can tell you now. He tried either to murder or kidnap you by means of the Zeppelin that came to Barborough. That the authorities gathered from one of the crew when the airship was wrecked in the North Sea a few days ago and the men rescued by a British patrol boat. Secondly, he did his level best to shoot you in the back this morning----"

"Is that so?" asked Barcroft. "I can just understand a man doing such a thing through violent personal motives, but for a mere international reason----"

"My dear fellow, there was the sum of ten thousand marks waiting to be earned."

"Yes," admitted Peter. "I know that. But only yesterday he fished me out of the Dingle Dell stream when I was almost on the point of being drowned. For why?"

"Ask me another," replied Entwistle. "At any rate, you will have cause to realise the actual existence of the Unseen Hand. But what happened just now, after he fired and missed?"

Peter Barcroft glanced at the clock. It wanted thirty seconds to complete the stipulated five minutes.

"I talked to him pretty straight," he said. "Shamed him a bit, I think. Anyway, I took four unused cartridges out of the revolver.

Being a six-chambered weapon one cartridge remained."

"Well?"

"I handed the pistol back to him; told him if he were still of the same mind he had yet another chance to settle with me. He didn't--"

"Great Scott!" exclaimed Entwistle striding towards the stairs. "You left him with a loaded revolver?"

Peter laid a detaining hand on the Secret Service man's shoulder.

"I gave him five minutes," he said. "And the time's up."

A pistol shot rang out from the upstairs room.

Siegfried von Eitelwurmer, otherwise Andrew Norton, had paid the penalty.

CHAPTER x.x.xVI

THE ELUSIVE OBJECTIVE

"By Jove! old man," exclaimed Kirkwood, "we're up against a big thing to-morrow."

Billy Barcroft merely nodded. It was "a big thing," this impending movement. Something that was well worth the risk, but at the same time the chances of the partic.i.p.ators in the business returning were very remote.

The two chums were pacing the port side of the quarter-deck of the "Hippodrome"--a long and comparatively narrow s.p.a.ce betwixt the rise of the deck-houses and the stern, and separated from the corresponding part on the starboard side by the inclined launching platform.

The seaplane-carrier was lying in a certain East Coast harbour, with steam raised ready to proceed at a moment's notice, and although her destination was supposed to be a strict secret, the nature of the forthcoming operations was known to all on board.

It was nothing less than a raid on Cuxhaven, where a considerable portion of the German High Seas Fleet was known to be "resting"

after a speculative but cautious cruise off the west coast of Jutland, the object being twofold--to exercise the crews and to impress upon the incredulous Danes the fact that the fleet of the Black Cross Ensign were willing and anxious to meet the British navy.

With their U-boats well out to sea, their ocean-going torpedo-boats forming a far-flung screen, and Zeppelins hovering overhead, the Hun "capital ships" had steamed in and out, keeping within their protective mine-fields: Having accomplished this imposing evolution the battleships of the fleet returned, part going to Cuxhaven, the rest to Wilhelmshaven, while the bulk of the torpedo flotillas anch.o.r.ed off the east side of Heligoland.

Once more the German Press had burst forth into a panegyric on the invincible and undaunted prowess of the fleet of the Fatherland, taking good care to impress upon the people that, although every opportunity had been offered to the British to engage in battle, the challenge had been declined.

The projected raid upon Cuxhaven was a reply to the Huns' empty boast. The seaplane carriers "Hippodrome," "Arena," "Cursus" and "Stadium," escorted by light cruisers and destroyers, were to proceed to a rendezvous twenty miles west of Heligoland. Sixty miles away the British battle cruisers were to "standby," ready, at a wireless call for a.s.sistance, to tear off at full speed to the succour of the small craft should the latter, regarded as an easy prey, be attacked by the big-gun ships of the German navy.

At the first blush of dawn twenty seaplanes were to start from their parent ships on their perilous flight over the Heligoland Bight and drop their powerful bombs upon the naval port of Cuxhaven--a feat that, knowing the formidable anti-aircraft defences, promised to be a forlorn hope; yet there was the keenest compet.i.tion amongst the airmen of the fleet to partic.i.p.ate in the "grand stunt."

The A.P. had carried out his promise to Barcroft. He had sold Billy the deeds of Mrs. Deringhame's house at Alderdene, and the flight-sub had sent them anonymously to Betty's mother.

It was a tremendous financial sacrifice on Billy's part. It had practically wiped up the bulk of his capital, but Barcroft cared not one jot for that. What troubled him was the fact that he could not ask Betty to marry him on his meagre pay. He had very little doubt but that the girl would do so, for during his last leave he had been much in her company.

"It wouldn't be fair to Betty," he soliloquised. "I must rake in some more cash, but goodness only knows how long it will take. One thing, we are both young, or I'm hanged if I would have the nerve to ask her to wait! Well, if this raid comes off successfully it will mean promotion. That's one blessing. If it doesn't--well, Billy Barcroft won't be in a position to worry about anything, I guess."

The flight-sub had completed his preparations. Two letters, one to his parents and one to Betty Deringhame, had been written, sealed and handed to the fleet-paymaster to be forwarded in the event of the writer's death. This unpleasant but necessary business performed, Barcroft dismissed the matter from his mind and concentrated his thoughts and energies on the work in hand.

"All correct, Jones?" he asked, addressing the air-mechanic who was putting the finishing touches to the seaplane that was to carry Barcroft and Kirkwood on their adventurous flight.

"All correct, sir," was the reply. "I've advanced the spark a trifle, sir she ought to simply buzz; but perhaps you'll see that everything's to your satisfaction."

Carefully Billy tested his controls, examined unions, contact breaker, and automatic lubricators. Success depended upon motor efficiency almost as much as upon the skill and courage of the pilot. The slightest hitch might spell disaster.

"There's the permission to part company," announced Kirkwood as a signal, made in response to a display of bunting from the yard-arms of the respective seaplane-carriers, was hoisted from the naval signal station. "Wonder if I'll see Old England again," he added in an undertone.

Already the cruisers were steaming out of harbour; not in the pomp of pre-war days with guards drawn up on the quarter-deck and bands playing as each vessel pa.s.sed the flagship. Silent and grim, huge emblems of seapower, they glided past the harbour batteries and, increasing speed to twenty-two knots, were soon out of sight.

With destroyers preceding and following, the tour seaplane-carriers were next to leave. On gaining the open sea they formed line abreast, surrounded by their vigilant escort; the light cruisers, reducing speed to that of the convoy, taking up station two miles astern.

In this formation the flotilla reeled off knot after knot without incident, until late in the evening, when two of the destroyers on the "Hippodrome's" starboard beam began a rapid fire that lasted nearly five minutes, breaking station and circling in a fashion that recalled the preliminary manoeuvres of a pair of cautious boxers.

"U-boat, somewhere over there," commented Fuller, who with Barcroft and the A.P. was on deck in preference to the somewhat boisterous ward-room. "I don't think they've got her. Wonder if she's dived and avoided the cordon. If so we'll have to look out."

"Hope she won't bag us at this stage of the proceedings," said Kirkwood. "At any rate, our quick-fires are manned, and it will be dark in another half-hour."

The two destroyers had resumed station, having signalled to the effect that no definite result was observed but it was believed that the U-boat's periscopes had been smashed by gun-fire.

"The trouble will come later, I think," said Barcroft when the message was communicated to the "Hippodrome's" officers. "If she isn't winged she'll rise to the surface after we're out of sight and wireless the news to the Heligoland signal station. The mere mention of seaplane carriers will put the Huns on the _qui vive_. However, that can't be helped; I'm turning in, you fellows, and I advise you to do the same."

Well before dawn the airmen detailed for the raid were roused from their sleep, or rather their efforts to slumber, since few were sufficiently proof against the excitement of the forthcoming expedition to enjoy a good night's rest.

Breakfast over, the members of the forlorn hope donned their leather coats and flying helmets, and a.s.sembled aft for final instructions from the wing commander.

"There is to be no easing down to keep pace with the slowest machine," were his instructions. "Each man is to go for his objective at top speed. You have noted the positions of the various batteries, I trust? It would be well to leave the Glienicke Redoubt well on your left. It's the only one, I believe, that mounts the latest Krupp's antis. On no account must the bombing seaplane attempt to encounter hostile aircraft on the outward flight: leave that task to the escorting planes. If, however, you fall in with any Zeppelins, attack immediately. One more point: should the situation necessitate the withdrawal of the seaplane-carriers and their escorts you know your instructions? Good. Well, gentlemen, that is all I have to say, beyond wishing you the best of luck and a safe return."

Barcroft's machine was the last to leave the "Hippodrome's"

launching platform, and the last but one of the raiding craft. It was still dark. The misty outlines of the nearmost biplanes could be just discerned as they rose swiftly and steadily above the invisible destroyers. The crews of the latter gave the airmen three rousing cheers as they swept overhead, but the tribute was wasted. The farewell greetings were drowned by the roar of the engines.

As dawn began to break Billy made a rather disconcerting discovery.

His seaplane was now the last of the procession. It had been over hauled by the one from the "Cursus," and what was more she was slowly yet surely dropping astern.