Chapter 4

_The Invisible Ambassador_

Fredegonde Valmy implicated in the conspiracy! That was the first thought that flashed into Dick's mind as he recovered consciousness. He might have suspected it! But the idea that the girl he loved was bound up with the murderous gang that was attacking the very foundations of civilization chilled him to the soul.

Dick had been picked up a few minutes after he had been struck down, identified by Colonel Stopford as he was about to be removed to a hospital, and carried into the White House. Order had been restored by the arrival of a detachment of troops from Fort Myers, the severed cables located and mended, and by midnight the interior of the Presidential home had been made habitable again.

President Hargreaves was gone--kidnapped despite the utmost efforts to protect him; and it was impossible to conceal that fact from the world. But the wheels of government still revolved. All night an emergency council sat in the White House, and, deciding that in a time of such grave danger heroic means must be adopted, with the consent of such of the Congressional leaders as could be summoned, a Council of Defence was organized.

The whole country east of the Mississippi was placed under martial law. The fleet and army were put on a war footing. Flights of airplanes were assembled at numerous points along the eastern seaboard. To this Council Donald was attached as head of Intelligence for the Eastern Division. Yet all this availed little unless the location of the Invisible Empire could be ascertained, and, despite telegraphic reports that came in hourly, alleging to have discovered its headquarters, nothing had been achieved in this direction.

* * * * *

The garment taken from the slain soldier had been examined by a half-dozen of the leading chemists of the East. Pending the arrival from New York of the celebrated Professor Hosmeyer, it was deposited under military guard in a dark closet. The result was unfortunate. The garment exhibited to the assembled scientists was a mere bifurcated silken bag.

The gas with which it had been impregnated, though it had been heavy enough to adhere to the fabric for hours, had also been volatile enough to have disappeared completely, leaving a residue which was identified as a magnesium isotope.

Equally spectacular had been the disappearance of Mademoiselle Fredegonde Valmy. A cable from the Slovakian Ambassador had arrived a few hours later, denying her authenticity. And with her disappearance came the discovery that she had been at the head of an espionage system with ramifications in every state department, and in every statesman's home.

Three days passed with no sign from the enemy. The Council sat all day. In the executive offices of the White House Dick toiled ceaselessly, planning, receiving reports, organizing the flights of airplanes at strategic points throughout his district. From time to time he would be summoned to the Council. At night he threw himself upon a cot in his office and slept a sleep broken by the constant arrival of messengers. And still there was no clue to the location of the headquarters of the marauders.

But in those three days there had been no sign of them. Hope had succeeded despair; in the rebound of confidence the populace was beginning to ridicule the nation-wide precautions against what were coming to be considered merely a gang of super-criminals. It was even whispered that President Hargreaves had not been kidnapped at all. The Freemen's Party accused the Government of a plot to subvert popular liberties.

* * * * *

Dick received a summons on the third evening. Utterly worn out with his work, he pulled himself together and made his way into the Blue Room, where the Council was assembled. Vice-president Tomlinson, an elderly man, was in the chair. A non-entity, pushed into a post it had been thought he would adorn innocuously, he had been overwhelmed by his succession to the chief office of State.

Tomlinson did not like Dick, or any of the hustling younger officers who, unlike himself, realized the real significance of the danger that overhung the country. He sat pompously in his leather chair, regarding Dick as he entered in obedience to the summons.

"Well, Captain Rennell, what have you to report to us this evening?" he inquired, as Dick saluted and stood to attention at the table.

"We're improving our concentrations, Mr. Vice-president. We've eight flights of seaplanes scouring the coast in the hope of locating the stronghold of the Invisible Emperor. We've--"

"I'm sick and tired of that title," shouted Tomlinson. He sprang to his feet, his face flushed with anger. His nerves had broken under the continuous strain. "I'll give you my opinion, Captain Rennell," he said. "And that is that this so-called Invisible Emperor is a myth.

"A gang of thieves has invented a paint that renders them inconspicuous, has created a panic, and is taking advantage of it to terrorize the country. The whole business is poppycock, in my opinion, and the sooner this bubble bursts the better. Well, sir, what have you to say to that?"

"Have you ever seen any of these men in their invisible clothing, if I may ask, Mr. Vice-president?" inquired Dick, trying to keep down his anger. His nerves, too, were badly frazzled.

"No, sir, I have not, but my opinion is that this story is grossly exaggerated, and that the persons responsible are the reporters of our sensational press!" thundered Tomlinson.

* * * * *

He looked about him, a weak man proud of having asserted his authority. Somebody laughed.

Tomlinson glared at Dick, his rubicund visage purpling. But it was not Dick who had laughed. Nor any one at the council table.

That laugh had come from the wall beside the door. Again it broke forth, high-pitched, cold, derisive. All heads turned as if upon pivots to see who had uttered it.

"Good God!" exclaimed Secretary Norris, of the War Department, and slumped in his chair.

Five feet eight inches from the floor a pair of grey eyes looked at the Council members out of emptiness. Grey eyes, a man's eyes, cool, contemptuous, and filled with authority, with a contemptuous sense of superiority that left every man there dumb.

Dick was the first to recover himself. He stepped forward, not to where the invisible man was standing, but to a point between him and the door.

That cold laugh broke forth again. "Gentlemen, I am an ambassador from my sovereign, who chooses to be known as the Invisible Emperor," came the words. "As such, I claim immunity. Not that I greatly care, should you wish to violate the laws of nations and put me to death. But, believe me, in such case the retribution will be a terrible one."

Suddenly the envoy peeled off the gas-impregnated garments that covered him. He stood before the Council, a fair-haired young man, clad in the same fashion of trim black uniform as the bayonetted soldier had worn upstairs three nights before.

He bowed disdainfully, and it was Tomlinson who shouted:

"Arrest that man! I know his face! I've seen it in the papers. He's Von Kettler, the murderer who escaped from jail in an invisible suit."

"Oh, come, Mr. Vice-president," laughed Von Kettler, "are you sure this isn't all very much exaggerated?"

Tomlinson sank back in his chair, his ruddy face covered with sweat. Dick stared at Von Kettler. A suspicion was forming in his mind. He had seen eyes like those before, dark instead of grey, and yet with the same look of pride and breeding in them; the look of the face, too, impossible to mistake--he knew!

Fredegonde Valmy was Von Kettler's sister!

* * * * *

"Well, gentlemen, am I to receive the courtesies of an ambassador?" inquired Van Kettler, advancing.

"You shall have the privileges of the gallows rope!" shouted Tomlinson. "Arrest that man at once, Captain Rennell!"

"Pardon me, Mr. Vice-president," suggested the Secretary for the Navy blandly, "but perhaps it would be more desirable to hear what he has to say."

"Immunity for thieves, robbers, murderers!"

"Might I suggest," said Von Kettler suavely, "that, since the United States has honored my master by placing itself upon a war footing, it has accorded him the rights of a belligerent?"

"We'll hear you, Mr. Von Kettler," said the Secretary of State, glancing along the table. Three or four nodded, two shook their heads: Tomlinson only glared speechlessly at the intruder. Von Kettler advanced to the table and laid a paper upon it.

"You recognize that signature, gentlemen?" he asked.

At the bottom of the paper Dick saw scrawled the bold and unmistakable signature of President Hargreaves.

"An order signed by the President of your country," purred Von Kettler, "ordering your military forces replaced upon a peace footing, and the acceptance of our conditions. They are not onerous, and will not interfere with the daily life of the country. Merely a little change in that outworn document, the Constitution. My master rules America henceforward."

Somebody laughed: another laughed: but it was the Secretary of State who did the fine thing. He took up the paper bearing what purported to be President Hargreaves's signature, and tore it in two.

"The people of this country are her rulers," he said, "not an old man dragooned into signing a proclamation while in captivity--if indeed that is President Hargreaves's signature."

* * * * *

There came a sudden burst of applause. Von Kettler's face became the mask of a savage beast. He shook his fist furiously.

"You call my master a forger?" he shouted. "You yourselves repudiate your own Constitution, which places the control of army and navy in the hands of your President? You refuse to honor his signature?"

"Listen to me, Mr. Von Kettler!" The voice of the Secretary of State cut like a steel edge. "You totally mistake the temper of the people of this country. We don't surrender, even to worthy adversaries, much less to a gang of common thieves, murderers, and criminals like yourselves. You have been accorded the privilege you sought, that of an envoy, and that was straining the point. Show yourself here again after two minutes have elapsed, and you'll go to the gallows--for keeps."

"Dogs!" shouted Von Kettler, beside himself with fury. "Your doom is upon you even at this moment. I have but to wave my arm, and Washington shall be destroyed, and with her a score of other cities. I tell you you are at our mercy. Thousands of lives shall pay for this insult to my master. I warn you, such a catastrophe is coming as shall show you the Invisible Emperor does not threaten in vain!"

With complete nonchalance the Secretary of State took out his watch. "One minute and fifteen seconds remaining. Captain Rennell," he said. "At the expiration of that time, put Mr. Von Kettler under arrest. I advise you to go back to your master quickly, Mr. Von Kettler," he added, "and tell him that we'll have no dealings with him, now or ever."

* * * * *

For a moment longer Von Kettler stood glaring; then, with a laugh of derision and a gesture of the hands he vanished from view. And, though they might have expected that denouement, the members of the Council leaped to their feet, staring incredulously at the place where he had been. Nothing of Von Kettler was visible, not even the eyes, and there sounded not the slightest footfall.

Dick sprang forward to the door, but his outstretched arms encountered only emptiness. In spite of the Secretary of State's instructions, he was almost minded to apprehend the man. If he could get him!

The corridor was empty. A guard of soldiers was at the entrance, but they did not block the entrance. Even now Von Kettler might be passing them! Why didn't his feet sound upon the floor? How could a bulky man glide so smoothly?

Perhaps because Dick was undecided what to do, Von Kettler escaped him. By the time he reached the guards he knew he had escaped. Suddenly there came an unexpected denouement. Somewhere on the White House lawn a guard challenged, fired. The snap of one of the silenced automatics answered him.

When Dick and the guards reached the spot, the man was lying in a crumpled heap.

"An airplane," he gasped. "Invisible airplane. I--bumped into it. Men--in it. The damned dogs!"

He died. Dick stared around him. There was no sign of any airplane on the lawn, nothing but the tents of the guards, white in the moonlight, and the grim array of anti-aircraft guns that Dick had placed there.

But behind the White House, in hastily constructed hangars, were a half-dozen of the latest pursuit airships--beautiful slim hulls, heavily armored, with armored turrets containing each a quick-firer with the new armor-piercing bullets. One of these ships, Dick's own, was kept perpetually warmed and ready to take the air.

* * * * *

Dick raced across the lawn, yelled to the startled guard in charge. The mechanics came running from their quarters. Almost by the time Dick reached it the ship was ready.

He twirled the helicopter starter, and she roared and zoomed, taking an angle of a hundred and twenty-five degrees upward off a runway of twenty yards. Into the air she soared, into the moonlight, up like an arrow for five hundred feet.

Dick pulled the soaring lever, and she hung there, buzzing like a bee as her helicopters, counteracting the pull of gravity, held her comparatively stable. He scanned the air all about him.

Washington lay below, her myriad lights gleaming. Immediately beneath him Dick saw the guns and the tents of the soldiers, and the little group that was removing the body of the murdered soldier on a stretcher. But there were no signs of any hostile craft.

Had the murdered man really bumped into an invisible airship, or had he only thought he had? Had those devils learned to apply the gas to the surfaces of airplanes? There was no reason why they should not have done so.

But surely the utmost ingenuity of man had not contrived to render a modern plane, with its metalwork and machinery, absolutely transparent?

* * * * *

And, again, how was it possible to have silenced the sound of engines, the whir of a propeller, so that there should be no auditory indication whatever of a plane's presence?

Dick looked all about him. Nothing was in the air--he could have sworn it. He replaced the soaring lever and banked in a close circle, his glance piercing the night. No, there was nothing.

Crash! Boom! The plane rocked violently, tossing upon gusts of air. A huge, gaping hole of blackness had suddenly appeared in the middle of the White House lawn. The tents were flat upon the ground. Through the rising smoke clouds Dick saw tongues of flame.

No shell that, but a bomb, and dropped from the skies less than five hundred feet from where Dick hovered. Yet there was nothing visible in the skies save the round orb of the moon.

A rush of wind past Dick's face! One of the vanes of the helicopter crumpled and fluttered away into the night. Dick needed no further persuasion. The dead soldier had not lied.

Von Kettler had begun the fulfillment of his threat!