The Phantom Airman

"Wants them to report progress at once, and let him know how matters stand," said Weissmann in a mocking tone. "He says he will come over himself, if necessary."

"Donnerwetter! Ask him to come, Professor. He might as well grill with his accomplices on the live wires, for that's where they'll be before the day is out, unless they abandon their futile search," replied Strauss.

"This fiend is a perfect wizard!" thought Keane, and his glance signified as much to Sharpe. "How he manages to get hold of these secrets is beyond me. And yet, there is a defect in his mad science, for he does not know that we're here, and that his own life is in our hands. Fool that he is, he will soon learn that the wit of an Englishman is more than a match for his boasted knowledge," and here the senior airman carefully withdrew a cartridge from his Webley and inserted another, silently–a cartridge that had a specific mission. His companion watched him and repeated the action with his own weapon, for he understood.

"Blitz! but I've half a mind to send for Tempest," mused the professor, who was still toying with the keys of the wireless instrument.

"Send for him, Professor," urged his accomplice. "Those Englishmen are getting too close to be pleasant. The British army of occupation will be carrying out a thorough search of the Schwarzwald if these men get away, and then where shall we be?"

"We are in the neutral zone, though," replied the other.

"But we're contravening the Peace Regulations, sir, and the English will not stand upon ceremony. It will be too late should these men get away."

"Donner und Teufel!" rasped out the angry professor. "Don't speak to me of the Peace Regulations. There will be no peace till Germany regains all and more than all she has lost. I will send for this Commissioner of Aerial Police, for I believe that he and his two accomplices, Keane and Sharpe, are the only ones so far who know anything that matters about the secret of the Schwarzwald," and he began to tap the keys, reeling out the words as he sent them.

Keane listened acutely for the cyphers of the code. They were:–

"Z–X–B–T–V–O–P…"

and he understood that Tempest was to come at once, make for Mulhausen aerodrome, then take a bee-line, east-north-east over the Schwarzwald until he saw a smoke column, where a suitable landing-ground would be found, and his accomplices would await him.

"Ach!" shrieked the professor, with a fiendish laugh. "The smoke column will mark his last resting-place. They shall all be buried together, these mad Englishmen. We will have more live wires stretched across his landing-ground, and as the wild boar died, so will these men die who dared to follow me into the Schwarzwald."

"The wild boar! Hoch! Hoch!" exclaimed his companion. "It is a fitting tribute for the English are swine!"

"And the Scorpion shall witness the inglorious end of these men," cried the professor, as a sudden idea came into his mind.

"Der Scorpion?" queried Fritz, looking up amazed from his task. "What do you mean, Professor?"

"Why, the Rittmeister will have finished his work in the Hamadian Desert this afternoon. His instructions are to resign the Sultanate of those regions for the present, for the skies will be thick with British scouts by to-morrow."

"But then he goes to Ireland to work with the revolutionists there, does he not, mein herr?"

"Ja! ja! but I will ask him to call here for a day or two before he proceeds. He will have much to tell us, and Spitzer, Carl and Max would like to see these dangerous opponents safely out of the way, for at present they are the only enemies to be considered."

"Gut!" ejaculated Strauss, catching something of the professor's enthusiasm.

Keane would have intervened before this, for he had noted Sharpe's impatience, but he intimated as well as he could by mute signs and otherwise, that the fiend was doing their work for them.

"Let him send this message first," he whispered in his companion's ears, "and then–" But the sentence was completed by further cabalistic signs.

Again the professor turned to the keys, and sent his last instructions through the ether waves to his confederate, the brigand of the eastern skies.

CHAPTER XX

"HANDS UP!"

"Haende in die hohe!" cried Keane as soon as the last message had been sent.

"Der Teufel!" gasped the professor as two swift shadows darted out from behind the curtain, and the two men whom he had just been discussing with such utter contempt confronted him and his accomplice with gleaming pistols.

"Hands up!" repeated Keane, anxious to give the professor another chance.

With a blasphemous oath the man of evil genius, who saw that he had been outwitted, reached for a small hand grenade which lay beside him on the table, and shouted:–

"Never!"

"Then take that!" cried the Englishman, and two puffs of greenish smoke, following a sharp crackle, burst simultaneously from the pistols, for they had both fired together.

The new Asphixor bullets took immediate effect. Both the Germans staggered, clutched their throats as though to ward off the effects of this new powerful gas recently discovered and adapted by that eminent British scientist, Sir Joseph Verne–then lurched and fell, whilst their opponents stepped back and quickly fitted on their safety masks.

"They are both sound asleep," observed Keane, when, the fumes having cleared away, he threw aside his respirator and carefully examined the unconscious men.

"Let them sleep," said Sharpe, who would have adopted even more drastic measures if he could have had his own way. "'Tis scant mercy they would have shown to us if we had been in their power."

"And now let us get to work, for they will awaken in seven or eight hours, and we have much to do. We must prepare for Colonel Tempest, and also for this raider," urged Keane.

"But they will not come to-day, Captain."

"Scarcely, but we must be prepared for anything. There are only a couple of us."

"Shall we secure these men, in case they awake earlier than the stipulated time?"

"No, let us remove their slumbering forms behind the curtain there; we will attend to them before they awake. I do not like the idea of strapping down unconscious men, even though they are criminals. We will watch them from time to time."

Then for the next half-hour they carried out a careful examination of the hangar and its contents. They were amazed at the intricate and wonderful mechanism with which the place was fitted. It seemed impossible that these things could have been transported hither without attracting attention. Parts of aeroplane wings, struts, propellers, engine-fittings, strange, weird-looking cylinders, retorts, analytical appliances, instruments and vessels for chemical research, powerful but silent dynamos, and numberless other things, all neatly arranged, and apparently in working order, half filled the place.

The further they carried their investigation the more were these two Englishmen bewildered by what they saw.

"Is it possible," gasped Keane, "or am I only dreaming? We have discovered the home of the super-alchemist. After this, nothing will surprise me."

"We have discovered the devil's workshop," replied Sharpe, who did not appear to be half so enraptured as his friend.

"Nay, we shall find the philosopher's stone, or the elixir vitae soon," replied Keane, continuing his investigation.

"We are more likely to find the elixir mortis than anything else," said the gloomy one. "This place gives me the shivers. I am sure that I shall have cold feet for the rest of my life."

"After this, Hermes and Geber will be dull reading," continued the enthusiast. "Give me the Schwarzwald every time for the real thrill of the alchemist."

"Their time might have been more profitably employed, at any rate," remarked Sharpe.

"Yes, it is a thousand pities that the wonderful brain which designed and organised all this should have had nothing better in view than brigandage and world revolution."

"More misdirected energy," moaned Sharpe; "the greatest brains often make the greatest criminals."

"You're a veritable misanthrope, Sharpe!" said his companion, laughing.

"I have reason to be," returned the other.