ealously secret city of Zbardk without betraying its
existence to the hated and feared hexans.

For a time the terrific rocket motors continued the deafening roar of
their continuous explosions, then, the desired velocity having been
attained, they were cut out and for hours the good ship "Bzark" hurtled
on through the void at an enormous but constant speed toward the distant
world of One, which it was destined never to reach.

"Captain Czuv! Hexan radiation, coordinates twenty two, fourteen, area
six!" cried the observer, and the commander swung his own telescopic
finder into the indicated region. His hands played over course and
distance plotters for a brief minute, and he stared at his results in
astonishment.

"I never heard of a hexan traveling that way before," he frowned.
"Constant negative acceleration and in a straight line. He must think
that we have been cleared out of the ether. Almost parallel to us and
not much faster--even at this long range, it is an easy kill unless
he starts dodging, as usual."

As he spoke, he snapped a switch and from a port under the starboard
wing there shot out into space a small package of concentrated
destruction--a rocket-propelled, radio-controlled torpedo. The rockets
of the tiny missile were flaming, but that flame was visible only from
the rear and no radio beam was upon it. Czuv had given it precisely the
direction and acceleration necessary to make it meet the hexan sphere
in central impact, provided that sphere maintained its course and
acceleration unchanged.

"Shall I direct the torpedo in the case the hexan shifts?" asked the
officer.

"I think not. They can, of course, detect any wave at almost any
distance, and at the first sign of radioactivity they would locate and
destroy the bomb. They also, in all probability, would destroy us. I
would not hesitate to attack them on that account alone, but we must
remember that we are upon a more important mission than attacking one
hexan ship. We are far out of range of their electro-magnetic detectors,
and our torpedo will have such a velocity that they will have no time to
protect themselves against it after detection. Unless they shift in the
next few seconds, they are lost. This is the most perfect shot I ever
had at one of them, but one shot is all I dare risk--we must not betray
ourselves."

* * * * *

Course, lookout, and rank forgotten, the little crew of two stared
into the na