Raiders Invisible Part 2

"Like h.e.l.l!" roared Chris Travers, and shot his whole weight backwards, grasping the service gun, whipping it around and yanking the trigger three times at the same instant.

Shooting at nothing! But, even above the bunched roar of the explosions, there pierced out a howl of agony that died quickly to a sobbing moan. Chris saw the automatic drop to the floor, felt the invisible body he had crashed into jerk away. He jumped to his feet, clutched at that body, and caught thin air. He swung around, listening, the service repeater in his hand.

Out of the air somewhere before him there came the sound of low, racking gasps, and also the slow noise of feet dragging heavily towards the cubby's door, towards the ladder that led up to the fore-and-aft cat-walk.

Chris sprang, slashing the b.u.t.t of the gun downwards. The lead was false. He hurtled jarringly into the door jamb, the gun thumping against the floor. The wind was knocked from him; the nausea of his wound swept him again with a surge of dizziness. But the painful scuffle of unseen feet ahead pulled him up once more; like a punch-drunk fighter he staggered out from the cubby to the ladder and hauled himself up the steps. He half-fell at the top, but his mind was clearing; and as he swayed there he knew what he had to do--saw the duty that lay before him....

More slowly, he crawled after the dragging footsteps and the gasps of the invisible raider, following them through the vast dimness of the interior of the dirigible ZX-1.

The chief operator on duty in the flagship of the Black Fleet swung round in his seat and yelled through into the bridge of the ma.s.sive battleship:

"Urgent, sir! From the ZX-1!"

A moment later the captain of the ship, for the fleet's admiral was out in a launch inspecting what little of the fallen ZX-2 was still floating on the surface, was at the operator's side, listening amazedly.

The operator read off, word for word, what Chris Travers had sent.

"... There was a contrivance planted aboard to blow up the ship and send it down in flames as the ZX-2 was. The thing that did it is--" he finished, and fell silent on that uncompleted sentence.

The captain's lined face expressed incredulity. "My G.o.d!" he burst out. "First the ZX-2, now-- That all?"

"Yes, sir. I can't get any answer or connection."

They stared at each other. Finally the captain spluttered:

"Is some maniac loose in this fleet? Don't sit there like a fool, man!

Get in touch with the _Saratoga_; tell 'em what you received; tell 'em to send some men up to that dirigible, wherever she is. We can't lose both of them!"

The operator's fingers skipped nimbly; even while he was speaking into the microphone, the red-faced captain had rushed back into the control bridge and was roaring:

"Signal the Admiral back here! Hurry!"

Things moved quickly then; small things, but significant. A casual eye glancing over the ranks of the Black Fleet as it lay around the scene of the tragedy, waiting for orders, would not have noticed any difference. The launch containing the fleet's admiral, which had been fussing about with its load of officers and various dignitaries, suddenly wheeled and pointed back for the mammoth flagship, in response to swift signals from the arms of a gob on her bridge; and, on the broad landing deck of the carrier, _Saratoga_, two three-seater planes, equipped with automatic clamps for a dirigible's rack, were wheeled up to the line.

Their props were spun over. But even before their c.o.c.kpits had been filled, an officer on the bridge of the flagship, and a dozen others throughout the fleet, cried:

"There she is!"

Over the eastern horizon, a gleaming sliver in the sunlight, thundered the ZX-1, straight for the array of the Black Fleet. Only a few men were aware of the drama-fraught message which had come down from her radio cubby, but her growing shape commanded the eyes of every sailor and officer alike who had time to watch. A few telescopic sights were trained on her as she bellowed ahead; the keen old eyes of a very perplexed and puzzled admiral were at one of them.

"Two planes hanging from her rack," he muttered, half to himself and half to the officers standing around him. "Both Navy. Say, they're dropping off! Not coming this way, either. Going northeast. Fast, too.

Can't see 'em any more.... Those men getting up from the _Saratoga_?

Good. We'll find out something soon. Here she comes!"

Closer and closer roared the dirigible. Two planes from the _Saratoga_ were swooping up to enter her rack, but the other two planes that shortly before had been suspended from it were gone--already vanished into the northeast.

"Don't understand this at all!" said the Admiral of the Black, or Pacific, Fleet of the United States Navy.

Things had broken well, Chris Travers considered. He had only wounded the invisible raider; but, luckily, had wounded him badly, so that, evidently, just one object was in the man's mind: to get back to where he came from, to where he could find help. He seemed oblivious of the scout that was following behind at the full speed of its mighty rotary motor, following him to his base, wherever it was.

"Just as well I didn't kill him," Chris muttered.

The rush of wind had cleared his brain; his faculties were steady and normal. Not so with the man in the plane he pursued. It was flying crazily, but clinging to one course, nevertheless--into the northeast, towards land, some two hundred and fifty miles over the horizon.

The great silver shape of the ZX-1, barren, now, of life, dropped away, speeding ever due west; the hazy dots and blur of smoke which denoted the motionless Black Fleet vanished. But Chris was in contact with the fleet's flagship once more, through the compact radio-telephone set of his scout. As he flew, his eyes fixed steadily on the plane ahead, he was rapping into the microphone the story of what had happened. He told of the invisibility of the strange marauder, of how accurately he had judged the time of his raids; of how he, Chris, had managed to prevent the destruction of the ZX-1.

"He uses a tremendously expansive gas resembling carbon monoxide," he went on. "It seeps into every cranny of the dirigible, killing everything. The crews got no warning; they didn't know what was happening; couldn't see him! Well, I managed to wound him on the ZX-1.

He beat it. I'm following him. If he lasts out, he'll go to where he came from, and we'll find out who's in back of all this. Let you know where his base is soon as I get there. Keep listening. Okay? Right; signing off."

Silence, then, between the scout and the flagship far behind....

On--on Time pa.s.sed. The scout's gas was down below the half-way mark.

They had covered two hundred miles now at a speed just bordering three hundred. The plane ahead looked uncanny with its apparently empty c.o.c.kpit, but Chris could see all too well that death was pressing at its invisible pilot. The big machine was literally staggering in its course as the hands on its control stick grew weaker; was yawing wildly, even as the ZX-1 had yawed after her crew had been slain by vapors they could not see.

"He's got to last out!" Chris muttered. "Got to!"

At that moment land appeared, and the fleeing plane altered its northeast course to due east with an abrupt jerk.

First it was a mere hazy line on the horizon; then it rose to a thrust of land, jutted with cloud-misted hill-tops. Then, as the two roaring specks that were airplanes came closer, heavy tropical foliage became distinct, and white slashes of surf breaking on the sh.o.r.e. This was the Azuero Peninsula, most western point of the Republic of Panama.

Aside from one small cl.u.s.ter of wretched huts, it was practically uninhabited. Guarded by dense growth, only one or two of the dusty paths which pa.s.sed for roads wandered aimlessly through its tangled creepers, trees and bush. To the southeast was the broad Gulf of Panama, doorway to the Ca.n.a.l; on the other sides this thumb of land was surrounded by the reaches of the Pacific.

The plane was obviously nearing its eyrie--dropping lower and lower, losing speed and alt.i.tude; and also threatening each moment to tumble down out of control into the smothering welter of olive-green below, with a dead, unseen body in its c.o.c.kpit.

But where was the landing field? They were now over the very heart of the Peninsula, and still Chris, searching through his telescopic sight, could see nothing but the monotonous roll of jungle. They must come to it soon, or be over to the Caribbean Sea and the Mosquito Gulf.

Then suddenly he started forward, staring. Of course there was no landing field in sight. The mystery plane needed none. It possessed the power of the helicopter: it could rise straight up or sink straight down.

From each one of the two k.n.o.b-like projections on its upper wing that had puzzled him previously, a propeller had risen and unfolded into long, flat blades. They whirled in circles of light in the sun; and the airplane beneath them poised, all but motionless, its main propeller swinging idly, and then began slowly to drop downwards.

But Chris, swooping nearby, was still perplexed. Dropping down to what? There was only the dense tropical growth beneath. He could see no trace of men, no clearing, however small, no base--nothing but the jungle.

"How in the d.i.c.kens--" he began; and then stopped. At that moment the jungle's secret was revealed.

As the helicopter-plane dropped to within a few hundred feet of it, a strip of the sea verdure split in two and reared up. It looked, at first, like magic. But from aloft Chris saw the trick and how the camouflage was worked. What appeared to be a slice of the jungle roof was, in reality, a metal framework cunningly plastered with layers of green growth. An oblong, some fifty by a hundred feet, it parted in the middle like a bridge that opens to let a steamer through, revealing the lair of the plane.

Soon more was revealed. Two tiny, green-painted huts stood in the minute clearing, and a few white-clad figures were by them, staring up at the plane sinking down and at the other plane which soared above like a buzzing mosquito.

One of the dwarfed figures in white waved an arm. The others around him darted into the left-side hut. Then the helicopter-plane's wheels touched the small s.p.a.ce allotted for it in the clearing, and the whirling propellers halted.