ort back to the
city whose name she bore, where her space-weary crew, worn by their long
"trick" in the awesomely oppressive depths of the limitless void, would
enjoy to the full their fortnight of refreshing planetary leave.

She was performing certain routine tasks--charting meteorites, watching
for derelicts and other obstructions to navigation, checking in
constantly with all scheduled space-ships in case of need, and so
on--but primarily she was a warship. She was a mighty engine of
destruction, hunting for the unauthorized vessels of whatever power or
planet it was, that had not only defied the Triplanetary League, but
were evidently attempting to overthrow it; attempting to plunge the
Three Planets back into the ghastly sink of bloodshed and destruction
from which they had so recently emerged. Every space-ship within range
of her powerful detectors was represented by two brilliant, slowly
moving points of light; one upon a great micrometer screen, the other in
the "tank"--the immense, three-dimensional, minutely cubed model of the
entire Solar System.

A brilliantly intense red light flared upon a panel and a bell clanged
brazenly the furious signals of the sector alarm. Simultaneously a
speaker roared forth its message of a ship in dire peril.

"Sector alarm! N. A. T. _Hyperion_ gassed with Vee-Two. Nothing
detectable in space, but...."

The half-uttered message was drowned out in a crackling roar of
meaningless noise, the orderly signals of the bell became a hideous
clamor, and the two points of light which had marked the location of the
liner disappeared in widely spreading flashes of the same high-powered
interference. Observers, navigators, and control officers were alike
dumfounded. Even the captain, in the shell-proof, shock-proof, and
doubly ray-proof retreat of his conning compartment, was equally at a
loss. No ship or thing could _possibly_ be close enough to be sending
out interfering waves of such tremendous power--yet there they were!

"Maximum acceleration, straight for the point where the _Hyperion_ was
when her tracers went out," the captain ordered, and through the fringe
of that widespread interference he drove a solid beam, reporting
concisely to G. H. Q. Almost instantly the emergency call-out came
roaring in--every vessel of the Sector, of whatever class or tonnage,
was to concentrate upon the point in space where the ill-fated liner had
last been known to be.

Hour after hour the grea