Elza clung close to me. "Everything will be ready soon."

I nodded. "They're going to mount a ray up here on the cliff. Grolier was telling me, for permanent protection--to stay here with the power house when we go out to the attack."

Silent with her thoughts she did not answer me. Sidewise, I regarded her solemn little face encased in its hood of fur. And then clumsily, for our furs were heavy and awkward, I put my arm about her.

"I love you, Elza. It's worth a great deal to be here alone with you."

"Jac, what will he do?" Her gaze was to the far-off City of Ice. "It seems so--so sinister, Jac, this silence from him. This inactivity. It is not like him to be inactive."

"He's there," I said. "Rolltar the Mars man--boastful fellow, blow-hard--he was telling some of us that in his opinion Tarrano had already run away."

"Never!" she exclaimed. "This is his last stand. He'll make it here--defeat us here--"

"Elza!"

She glanced momentarily at me, smiled a queer smile, and then gazed once more over the distant plain. "I do not mean I think he'll defeat us, Jac. I mean, that is his reasoning--make his last stand here--"

"He hasn't run away," I repeated. "I told Rolltar so. We got an outlaw connection into the Ice Palace today. For a moment only, and then it was discovered and broken off. But we had the image for a moment--it chanced to show Tarrano himself. But he's isolated now. Bretan said his isolation power--around the Ice Palace and the wall anyway--is greater than any image-ray we can send against it."

My heart leaped suddenly, for I saw Elza's eyes widen, fear spring to her face; heard the sharp intake of her breath, and felt her hand grip my arm.

"Jac! There's something wrong! See there? And you hear it?"

From the instrument room I heard a vague drumming. A hiss, and then a drumming growing louder. It was not a new sound, for now I remembered I had been conscious of it for several moments past. Our encampment was awake to it! A confusion down there; people running about; a figure dashing wildly into the instrument room. And the aerials on the power house began to snap viciously.

"Jac! What is it?"

"I don't know. See there, Elza? The sub-ray lights!"

The search-beams from our towers were inordinately active. Sweeping the empty snow-plain and the empty sky. Empty? To my fevered imagination they were peopled with enemies. And then one of the towers flashed on a sub-ray--the dull infra-red for envisaging the slow rays below the power of human sight. And another tower with its faint purple beam was using the ultra-violet.

"That drumming, Elza! That's a microphone--the big one they just erected near the instrument room. There's something coming! That's the magnified sound of some distant rush of air. Very faint sound, but they must have heard it on the ear-phones long ago. That microphone must have just been connected--"

Something coming? We could see nothing.

"Let's go down, Jac! We must get back--"

"I've got infra-red gla.s.ses--" I fumbled beneath my furs. But I did not have them.

"Jac--"

"Wait, Elza."

My gla.s.ses would have been useless, for the sub and ultra beams from the towers were disclosing nothing. I could tell that by the hasty searching sweeps they made. And then from the big Wilton tower, the newly connected Zed-ray flashed on, I could hear the load of it in the deepened, throaty hum from the power house. Its dirty brown beam sprayed out over the plain; then swung to the sky, caught something, hung motionless, narrowed into great intensity. The powerful Zed-ray, capturing the visibility of dense solids only.[24]

[Footnote 24: Similar doubtless to our present-day X-ray.]

There was something up there in the sky! The Zed-ray met resistance; we could see the sparks, and hear the snap of them coming like a roar from the microphone above the drumming. Met the resistance and conquered it; gradually the snapping roar died away.

"Jac! I see something! Something there--don't you see it?"

A luminous blur became visible in the nearer sky--moving blobs of silver luminosity in the mud-brown light of the Zed-ray. A hundred or more moving silver blobs. They were taking form. The silvery phosph.o.r.escent look faded, became grey-white. Took definite shape. Waving arms and legs! Bones bereft of flesh. Human skeletons! Limbs waving rhythmically.

Bony arms, with fingers clutching metal weapons. a.s.sailants coming at us through the air, stripped by the Zed-ray of clothing, skin, flesh, organs, to the naked bone. Skeletons with skulls of empty eye-sockets and set jaw-bones to make the travesty of human faces grim with menace!

CHAPTER x.x.xV

_Attack on the Power House_

Stricken with surprise and awe, Elza and I sat there motionless. Our encampment was in a turmoil of confusion--chaos, out of which very soon order came. The skeleton figures in the air--I saw now that there were nearer two hundred than one hundred--were perhaps two thousand feet away, and at an alt.i.tude of about the cliff-ledge where Elza and I were sitting.

They swept forward, bathed in the Zed-ray with all our other search-beams darkened to give it full sway. Momentarily I saw them clearer; metallic cylinders in bony fingers, and a metal mechanism of flight encasing, yet not touching the ribs.

"Jac! Why don't our rays--"

As though to answer Elza's unfinished question, one of our towers turned a disintegrating ray upon them. A narrow pencil-point of light, barely visible in this flat daylight. It swung up into our Zed-ray, searched and clung to one of the skeleton figures. Had it penetrated, the man would have been dissipated like a puff of vapor. But it did not; and then I knew that for that distance at least, this enemy's isolation power--individual barrage--was too great.

Yet the a.s.sailed figure wavered! Our amplifier gave out his shout--half fear, half admonition. The line of skeletons swung upward. Came on, but mounted so that I saw that they were making for the summit of the cliff above us--above our power house.

Their defense--invisibility, and a mere isolation barrage so that we could not harm them with our tower rays while they kept beyond range.

But what was their means of attack? Why would Tarrano....

"The power house," Elza answered; and I realized then that she had read my thoughts. The power house, if they could demolish it....

Our thoughts, questions and answers unspoken, flew fast; but the drama before us unfolded faster. With the knowledge that we could see them, these invaders cast aside a portion of their equipment to give them greater freedom. We could see the metal portions of the trappings falling like plummets. The skeleton images faded; and then as our tower withdrew the Zed-ray and our search-beams picked them up, we saw our enemies as they really were. Men clothed in a casing of cylindrical garments with the flying mechanisms strapped to their chests; some with visors and headpieces, nearly all with small weapons in their hands.

Keeping well away, they continued to mount. They were striving for the pinnacle of cliff-tops above us; but as our rays darted at them they halted, wavered; and now when nearly above the camp, they began mounting straight up.

"Jac! Look there!"

One of our tower vehicles was preparing to rise. Its ray, following the search-beams upward, was aimed at the invaders, but they were beyond its effective range. Their weapons of attack? I knew now.

"Suicides!"

Whether Elza said it, or merely thought it I do not know. One of the figures came down as though falling. A few seconds only; but though our search-beam showed it, the smaller rays for those seconds missed it.

Down--until no more than five hundred feet above us it checked its fall.

A giant of a man; and with his hand cylinder--in range now--he shot a bolt at our power house. It struck; I could see the flash, saw an aerial shatter before the charge went harmlessly into the body of the building.

Then one of our rays caught the man; his figure crumpled; the shower of sparks as his barrage was broken, exploded like a tiny bursting bomb; and as the sparks died, there was nothing where the man had been.

A suicide; but one of our aerials was shattered. And then others came down--not many, for it was grim business and the courage of them must have failed at the last. Falling bodies; tiny bolts striking the power house; the sparks--then empty air where living men had been.

Our tower left the ground. Some of our men, with small flying platforms strapped to them, were crowding its top. Its beams preceded it--but I saw the beams breaking intermittently as the bolts struck the power house. The invaders wavered with indecision. Some of them came down to voluntary death; others strove for the cliff-top; some took flight. Our tower swept into them; one of them, injured but not annihilated, fell with a crash into the encampment.

Above Elza and me was a maze of flashing beams; futile bolts; the puffs of myriad sparks. A bolt seemed to strike quite near where we were sitting; I drew Elza back and we crouched in the hollow of a rock. A body came hurtling down, crashed to the cliff-ledge almost at our feet with the sickening thump of mangled flesh and broken bones--hung an instant to give me a momentary glimpse of a face contorted in death agony; then rolled over and fell further down the jagged cliff.

Then above us presently there was silence and the drab empty sky. Our tower was back beyond the cliff-top. Soon it appeared; apparently unharmed, it came dropping down to its former place on the ground.