great spherical growths that
looked like enormous sponges. Of a sickly, pale green hue, these
growths overran everything; climbed the columns and were lost in the
shadows above the multitude of lights. The big sponge-like blossoms
expanded and contracted rhythmically. Breathing, they were, like living
things. Specially cultivated plant life to assist in maintaining the
oxygen supply balance by decomposition of carbon dioxide. A marvelous
artificial world!

* * * * *

"The streets and moving ways are in tunnels beneath the soil," Pegrani
was explaining. "What lies before you is the city of Ilen-dar, capital
city of the empire, and like all other cities of Antrid, it is
self-sustaining. The vegetation is inedible, all of our food is
synthetic and highly concentrated. You were fed by intravenous
injection while under the influence of the language machines. Our heat
and power is obtained from the internal fires of Antrid, and, alas,
these are being exhausted with great rapidity. Our shortage of power is
becoming acute, and again our peoples are facing extinction."

That explained their need for the k-metal. It came to Blaine in a flash
that Antrid was in sore straits and that this expedition to Earth had
more back of it than had been revealed. Even with the supply of k-metal
Antazzo had stolen, they could not carry on forever.

A screaming object went hurtling through the blackness over their
heads. Something, a vehicle of enormous size with rows of lighted ports
on the under side, that roared its way under the roof of copper and was
gone in an instant.

"One of our monorail cars," Pegrani told them: "a complete system
interconnects all cities and divisions. They are capable of circling
the globe in a day of your time."

Their familiarity with conditions on Earth was astonishing. Probably
Antazzo was but one of many spies who had been sent to the inner
planets. Pegrani discussed the speed in their own terms.

* * * * *

Someone had crept up behind them; a slight, olive-skinned youth who
touched Blaine softly on the shoulder. Pegrani did not see. He was
pointing into the distance and expounding on the merits of the monorail
system. The youth touched a finger to his lips to enjoin silence, and
thrust a crumpled ball of metal foil into Blaine's hand before the
pilot realized his intention. A message, undoubtedly!

Some instinct, or som