a train at Culebra, we may be able to
get home by dark. You must remember that we rode a long way with the
lieutenant. Culebra is almost to the Pacific. The locks are there, or near
there."

"We can get a train, I guess," Peter said, sleepily. "I wonder if any of
the boys are sitting up for us?"

"You bet they're out hunting for the two of us," Jimmie said. "It takes
one half of our party to keep the other half from getting killed," he
added.

There were still no signs of the canal line. The jungle was as dense as
ever, and seemed more desolate and uncanny than ever under the growing
light of day. As the sun arose and looked down into the green pools vapors
arose, vapors unpleasant to the nostrils and bewildering to the sight.

Presently the boys came to a little knoll from which they could look a
long way into the jungle stretching around them. Below were slimy
thickets, tangles of creepers and vines which seemed to be sentient, but
no signs of the work of man. It was now eight o'clock in the morning, and
the boys were worn out and hungry.

"If they're out lookin' for us," Jimmie said, "I'll give 'em somethin' to
follow. Watch me."

"But they won't be anywhere around here," Peter said, as Jimmie began
gathering dry twigs and branches from the ground.

"They'll begin where Lieutenant Gordon left us," insisted the boy. "Now
you see if I don't wake some Boy Scout up. Here, you carry this bunch of
wood over to that other knoll."

"All right," Peter said. "Perhaps another jaguar will see the signal and
give us a call."

In a short time the boys had gathered two great piles of dry leaves and
branches lying some fifty feet apart. Then a quantity of green boughs were
gathered and placed on top of the dry fuel. When matches were touched to
the piles a dense smoke ascended far above the tops of the trees. There
were two straight columns of it lifting into the sky above the jungle.

"There!" cried Jimmie wiping the sweat from his face, for the morning was
hot and the work had been arduous, "if there is a Boy Scout within ten
thousand miles he'll know what those two columns of smoke mean."

"Of course," said Peter. "If he's ever been out camping."

In the Indian signs adopted by the Boy Scouts of America one column of
smoke means:

"The camp is here."

Two mean:

"Help! I am lost."

Three mean:

"We have good news."

Four mean:

"Come to council."

When the dry wood burned away the boys piled on more,