thing of the other man.

"Sounds like he had been running and was just catching his
breath," was Billie's mental comment.

After some minutes the man's breathing became more quiet and
Billie heard him slowly descending the stairs.

"This won't do," thought Billie. "He probably has some kind of a
light, and if he gets on the landing and I'm up here, I'll be
like a man up a tree."

The lad sat down and slowly slid toward the bottom.

Being only a few steps from the landing, Billie was down first.
He crowded to the right and listened.

The other was now nearly on the landing. Now he was on the
landing, hugging the wall on the side opposite Billie. Now they
passed each other, or rather the man passed Billie, for Billie
stood perfectly still.

It seemed as though he must hear Billie's breathing, but if he
heard anything he must have thought it his own echo, never
dreaming that he was not alone in the passage.

Now Billie could hear him ascending the stairs leading to
Santiago's house, and his hope rose high.

"He must know how to open the floor," thought Billie. "I'll be
right there when he does."

Silently as a cat Billie crept up the stairs behind his unknown
companion.

Near the top the man stopped and a minute later he flashed an
electric light against the stone overhead. Another minute and he
heaved with the top of his head and the slab slid back.

"And now," exclaimed Billie in a deep voice, "put your hands over
your head!"

Whether from fear or from the unparalleled surprise caused by
hearing a human voice at such a time and in such a place, instead
of obeying Billie's command, Strong's hands--for Strong it
was--fell limp at his side and his electric torch fell to the
stones beneath his feet.

"All right," continued Billy, "if that's the way you feel about
it; but just remember that a single false move and I'll cut this
automatic loose among your ribs. Now climb out a step at a time."

With face as white as marble at the shock he had just sustained,
Strong obeyed implicitly and Billie was soon standing on the
stone patio, looking Strong in the face.

"You're a good one, you are," he said sarcastically. "I should
think you'd be ashamed to call yourself an American."

"What do you mean?" asked Strong in a trembling voice.

"Why, first of all, stealing from the bank, and then selling your
own countrymen to the Mexicans."

"Who have I sold?"

"Do you mean to say that you didn't sell Gen. Funst