ray could pass.

As the _Silver Sliver_, crawling along at a bare five hundred miles an
hour, approached that transparent, brilliantly violet wall of
destruction, a light of the same color filled her control room and as
suddenly went out; flashing on and off again and again.

"Giving us the once-over, eh?" Cleveland asked. "That's something new,
isn't it?"

"Yes, it's a high-powered ultra-wave spy," Rodebush returned. "The light
is simply a warning, which can be carried if desired. It can also carry
voice and vision...."

"Like this," Samms' voice interrupted from a speaker upon the pilot's
panel and his clear-cut face appeared upon the television screen. "I
don't suppose Fred thought to mention it, but this is one of his
inventions of the last few days. We are just trying it out on you. It
doesn't mean a thing though, as far as the _Sliver_ is concerned. Come
ahead!"

A circular opening appeared on the wall of force, an opening which
disappeared as soon as the plane had darted through it; and at the same
time her landing-cradle rose into the air through a great trap-door.
Slowly and gracefully the space-plane settled downward into that
cushioned embrace. Then cradle and nestled _Sliver_ sank from view and,
turning smoothly upon mighty trunnions, the plug of armor drove solidly
back into its place in the metal pavement of the mountain's lofty
summit. The cradle-elevator dropped rapidly, coming to rest many levels
down in the heart of the Hill, and Cleveland and Rodebush leaped lightly
out of their transport, through her still hot outer walls. A door opened
before them and they found themselves in a large room of unshadowed
daylight illumination; the office of the Chief of the Triplanetary
Service. Calmly efficient executives sat at their desks, concentrating
upon problems or at ease, according to the demands of the moment;
agents, secretaries, and clerks, men and women, went about their wonted
tasks; televisotypes and recorders flashed busily but silently--each
person and machine an integral part of the Service which for so many
years had been carrying an ever-increasing share of the load of
governing the three planets.

"Right of way, Norma?" Rodebush paused before the desk of Virgil Samms'
private secretary. She pressed a button and the door behind her swung
wide.

"You two do not need to be announced," the attractive young woman
smiled. "Go right in."

Samms met them at the door eagerly, shaking hands par