alboon nodded
his comprehension and going outside, pointed upward toward the largest
of the eleven suns visible, motioning its rising and setting, four
times.

He then invited the visitors, in unmistakable sign language, to
accompany him as guests of honor, but Seaton refused.

"Lead on, MacDuff, we follow," he replied, explaining his meaning by
signs as they turned to enter the vessel. The slaves followed closely
until Crane remonstrated.

"We don't want them aboard, do we, Dick? There are too many of them."

"All right," Seaton replied, and waved them away. As they stepped back
the guard seized the nearest, a woman, and forced her to her knees;
while a man, adorned with a necklace of green human teeth and carrying a
shining broadsword, prepared to decapitate her.

"We must take them with us, I see," said Crane, as he brushed the guards
aside. Followed by the slaves, the party entered the Skylark, and the
dark green people embarked in their airplanes and helicopters.

Nalboon rode in a large and gaily-decorated plane, which led the fleet
at its full speed of six hundred miles an hour, the Skylark taking a
placing a few hundred yards above the flagship.

"I don't get these folks at all, Mart," said Seaton, after a moment's
silence. "They have machines far ahead of anything we have on Earth and
big guns that shoot as fast as machine-guns, and yet are scared to death
at a little simple sleight-of-hand. They don't seem to understand
matches at all, and yet treat fire-works as an every-day occurrence."

"We will have to wait until we know them better," replied Crane, and
DuQuesne added:

"From what I have seen, their power seems to be all electrical. Perhaps
they aren't up with us in chemistry, even though they are ahead of us in
mechanics?"

* * * * *

Flying above a broad, but rapid and turbulent stream, the fleet soon
neared a large city, and the visitors from Earth gazed with interest at
this metropolis of the unknown world. The buildings were all the same
height, flat-roofed, and arranged in squares very much as our cities are
arranged. There were no streets, the spaces between the buildings being
park-like areas, evidently laid out for recreation, amusement, and
sport. There was no need for streets; all traffic was in the air. The
air seemed full of flying vehicles, darting in all directions, but it
was soon evident that there was exact order in the apparent confusion,
each