projected himself into the torpedo he
had lined up so many times the previous day. With the automatic motions
set to hold him stationary in the tiny instrument compartment of the
craft, now traveling at a velocity many times that of light, he set to
work. A glance located the detector mechanism, a set of short-wave coils
and amplifiers, and a brief study made plain to him the principles
underlying the directional loop finders and the controls which guided
the flying shell along the path of the tracer ray. He then built a
detector structure of pure force immediately in front of the torpedo,
and varied the frequency of his own apparatus until a meter upon one of
the panels before his eyes informed him that his detector was in perfect
resonance with the frequency of the tracer ray. He then moved ahead of
the torpedo, along the guiding ray.

"Guiding it, eh?" Dunark congratulated him.

"Kinda. My directors out there aren't quite so hot, though. I'm a trifle
shy on control somewhere, so much so that if I put on anywhere near full
velocity, I lose the ray. Think I can clear that up with a little
experimenting, though."

He fingered controls lightly, depressed a few more keys, and set one
vernier, already at a ratio of a million to one, down to ten million. He
then stepped up his velocity, and found that the guides worked well up
to a speed much greater than any ever reached by Fenachrone vessels or
torpedoes, but failed utterly to hold the ray at anything approaching
the full velocity possible to his fifth-order projector. After hours and
days of work and study--in the course of which hundreds of the
Fenachrone vessels were destroyed--after employing all the resources of
his mind, now stored with the knowledge of rays accumulated by hundreds
of generations of highly-trained research specialists in rays, he became
convinced that it was an inherent impossibility to trace any ether wave
with the velocity he desired.

"Can't be done, I guess, Mart," he confessed, ruefully. "You see, it
works fine up to a certain point; but beyond that, nothing doing. I've
just found out why--and in so doing, I think I've made a contribution
to science. At velocities well below that of light, light-waves are
shifted a minute amount, you know. At the velocity of light, and up
to a velocity not even approached by the Fenachrone vessels on their
longest trips, the distortion is still not serious--no matter how fast
we want to travel in the _Skyla