mountains, how we endured the heat of
the desert I cannot tell," went on the weak voice of the man on the bed
of straw. "We reached Zacatecas, and then Bushnell went for another
balloon. He knows friends who have money and power, and he will get the
balloon--if he lives."

"But the proof--the proof that you were going to show us?"

"It is here! Look!"

From beneath the straw Jack Burk drew forth a queer little figure of
solid gold--a figure like the pictures of Aztec gods, which Frank had
seen.

"This is proof!" declared the man. "It is some of the treasure we
brought from the palace. Bushnell took the rest."

The professor excitedly grasped the little image, and gazed searchingly
at it.

"It is all right--it is genuine!" he finally exclaimed.

"Of course it is genuine!" said the man on the bed of grass. "And there
are more in the Silver Palace. There the treasures of the Aztecs were
hidden, and they have remained. The country all around is full of fierce
natives, who hold the palace in awe and prevent others from reaching it.
They have kept the secret well, but----"

"Vot vos dot?" interrupted Hans.

At some distance on the plain outside the hut were wildly galloping
horses, for they could hear hoof-beats and loud cries. Then came a
fusillade of pistol shots!

[Illustration: "Frank began shooting, and his first bullet brought down
one of the ponies of the pursuers." (See page 14)]

CHAPTER II.

GONE.

"Bandits!" cried Jack Burk. "It may be Pacheco!"

"Pacheco?" questioned Frank.

"Pacheco, the human hawk! He haunts the mountains and the desert. He
pursued us across the desert, but we escaped him. I have been in hiding
here to avoid him. He believes we brought much treasure from the
mountains."

The professor had leaped to the door, and was looking away on the plain.
Now he cried, excitedly:

"Look here! A band of horsemen pursuing a white man--plainly an
American. Look, he is shooting again!"

Once more the shots were heard.

Frank ran to the door, catching up a rifle that had been leaning against
the wall of the hut, for he knew he was in a "bad man's land."

"Stand aside!" he shouted, forcing his way past the professor. "No
countryman of mine can be in danger that I do not try to give him a
helping hand."

"What do you mean to do?"

"Get a crack at those Greasers."

"You are crazy! You will bring the entire band down on us!"

"Let 'em come! One Yankee is good for six Grease