ave 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 phosphorescent
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. Assailants 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 XXXV

_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 altitude 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 ske