With a wave of the hand and amid a cheer that seemed to rend the sky
the Golden Eagle shot forward as Frank set the starting lever and
rushed along over the level plane like a thing of life. After a short
run she rose skyward in a long level sweep, just as the daylight began
to show in a faint glow in the east.

It rapidly grew lighter as the boys rose and as they attained a height
of 1,500 feet and flew forward at sixty miles an hour above the vast
level tract of gravelly desert, by looking backward they could see the
forms of the two ships, like tiny toys, far behind and below them. On
and on they flew, without seeing a trace of the professor or the band
that had undoubtedly made him prisoner.

"We must have overshot the mark," said Frank, as he set a lever so as
to swing the aeroplane round. "We shall have to fly in circles till we
can locate the spot where the Patagonians have taken him."

They flew in this manner for some time, sometimes above rugged broken
land with great sun-baked clefts in it, and sometimes above level
plains overgrown with the same dull colored brush they had noticed
fringing the coast.

Suddenly Billy called attention to a strange thing. All about them
were circling the forms of huge birds. Some of them measured fully ten
feet from wing tip to wing tip. They had bald, evil-looking heads and
huge, hooked beaks.

"They are South American condors, the largest birds in existence,"
cried Harry, as the monstrous fowls, of which fully a hundred were now
circling about the invaders of their realm, seemed to grow bolder and