Astounding Stories of Super-Science, March 1930 Part 9

And Snap's helio mirrors, attuned for an hour now to pick up the faintest signal, were motionless.

"If he has concentrated any appreciable amount of radio-active ore,"

said Snap, "we should get an impulse from its Gamma rays."

But our receiving s.h.i.+eld was dark, untouched. We tried taking hydrogen photographic impressions of the visible moon surface. A sequence of them, with stereoscopic lenses, forty-eight to the second. Our mirror-grid gave the magnified images; the spectro-heliograph, with its wave-length selection, pictured the mountain-levels, and slowly descended into the deepest seas.

There was nothing.

Yet in those moon caverns--a million million recesses amid the crags of that tumbled, barren surface--the pin-point of movement which might have been Grantline's expedition could so easily be hiding! Could he have the ore insulated, fearing its Gamma rays would betray its presence to hostile watchers?

Or might disaster have come to him? Or he might not be upon this hemisphere of the moon at all....

My imagination, sharpened by fancy of a lurking menace which seemed everywhere about the Planetara this voyage, ran rife with fears for Johnny Grantline. He had promised to communicate this voyage. It was now, or perhaps never.

Six-thirty came and pa.s.sed. We were well beyond the earth's shadow now.

The firmament blazed with its vivid glories; the sun behind us was a ball of yellow-red leaping flames. The earth hung, opened to a huge, dull-red half-sphere.

We were within some forty thousand miles of the moon. Giant white ball--all of its disc visible to the naked eye. It poised over the bow, and presently, as the Planetara swung upon her course for Mars, it s.h.i.+fted sidewise. The light of it glared white and dazzling in our tiny side windows.

Snap, with his habitual red celluloid eyeshade shoved high on his forehead, worked over our instruments.

"Gregg!"

The receiving s.h.i.+eld was glowing a trifle! Gamma rays were bombarding it! It glowed, gleamed phosph.o.r.escent, and the audible recorder began sounding its tiny tinkling murmurs.

Gamma rays! Snap sprang to the dials. The direction and strength were soon obvious. A richly radio-active ore body, of considerable size, was concentrated upon this hemisphere of the moon! It was unmistakable.

"He's got it, Gregg! He's--"

The tiny helio mirrors began quivering. Snap exclaimed triumphantly, "Here he comes! By G.o.d, the message at last! Bar off that light!"

I flung on the absorbers. The moonlight bathing the little room went into them and darkness sprang around us. Snap fumbled at his instrument board. Actinic light showed dimly in the quivering, thumbnail mirrors.

Two of them. They hung poised on their cobweb wires, infinitely sensitive to the infra-red light-rays Grantline was sending from the moon. The mirrors in a moment began swinging. On the scale across the room the actinic beams from them were magnified into sweeps of light.

The message!

Snap spelled it out, decoded it.

"_Success! Stop for ore on your return voyage. Will give you our location later. Success beyond wildest hopes--_"

The mirrors hung motionless. The s.h.i.+eld, where the Gamma rays were bombarding, went suddenly dark.

Snap murmured, "That's all. He's got the ore! 'Success beyond wildest hopes.' That must mean an enormous quant.i.ty of it available!"

We were sitting in darkness, and abruptly I became aware that across our open window, where the insulation barrage was flung, the air was faintly hissing. An interference there! I saw a tiny swirl of purple sparks.

Someone--some hostile ray from the deck beneath us, or from the spider bridge that led to our little room--someone out there trying to pry in!

Snap impulsively reached for the absorbers to let in the outside light--it was all darkness to us outside. But I checked him.

"Wait!" I cut off our barrage, opened our door and stepped to the narrow metal bridge.

"Wait, Snap! You stay there." I added aloud, "Well, Snap, I'm going to bed. Glad you've cleaned up that batch of work."

I banged the door upon him. The lacework of metal bridges and ladders seemed empty. I gazed up to the dome, and forward and aft. Twenty feet beneath me was the metal roof of the cabin superstructure. Below it, both sides of the deck showed. All patched with moonlight.

No one visible down there. I descended a ladder. The deck was empty. But in the silence something was moving! Footsteps moving away from me down the deck! I followed; and suddenly I was running. Chasing something I could hear, but could not see. It turned into the smoking room.

I burst in. And a real sound smothered the phantom. Johnson the purser was sitting here alone in the dimness. He was smoking. I noticed that his cigar held a long, frail ash. It could not have been him I was chasing. He was sitting there quite calmly. A thick-necked, heavy fellow, easily out of breath. But he was breathing calmly now.

He sat up with amazement at my wild-eyed appearance, and the ash jarred from his cigar.

"Gregg! What in the devil--"

I tried to grin. "I'm on my way to bed--worked all night helping Snap with those d.a.m.n Earth messages."

I went past him, out the door into the main interior corridor. It was the only way the invisible prowler could have gone. But I was too late now--I could hear nothing. I dashed forward into the main lounge. It was empty, dim and silent, a silence broken presently by a faint click--a stateroom door hastily closing. I swung and found myself in a tiny transverse pa.s.sage. The twin doors of A 22 and A 20 were before me.

The invisible eavesdropper had gone into one of these rooms! I listened at each of the panels, but there was only silence within.

The interior of the s.h.i.+p was suddenly singing with the steward's siren--the call to awaken the pa.s.sengers. It startled me. I moved swiftly away. But as the siren shut off, in the silence I heard a soft, musical voice:

"Wake up, Anita--I think that's the breakfast call."

And her answer: "All right, George. I hear it."

CHAPTER IV

_A Burn on a Martian Arm_

I did not appear at that morning meal. I was exhausted and drugged with lack of sleep. I had a moment with Snap, to tell him what had occurred.

Then I sought out Carter. He had his little chart-room insulated. And we were cautious. I told him what Snap and I had learned: the Gamma rays from the moon, proving that Grantline had concentrated a considerable ore-body. I also told him the message from Grantline.

"We'll stop on the way back, as he directs, Gregg." He bent closer to me. "At Ferrok-Shahn I'm going to bring back a cordon of Interplanetary Police. The secret will be out, of course, when once we stop at the moon. We have no right, even now, to be flying this vessel as unguarded as it is."

He was very solemn. And he was grim when I told him of the invisible eavesdropper.

"You think he overheard Grantline's message?"

"I don't know," I said.