paper.

Ned took them out, stirred the fire to a sudden glow, and bent over the
figures and lines on the sheets. His face grew thoughtful as he looked.

"What is it?" Jimmie asked.

Ned held out the rolls.

"This one," he said, "is a drawing of the Gatun dam, and this other is a
crude sketch of the basement of the _Daily Planet_ building in New York."

"Gee!" cried the boy. "Are they goin' to blow that up, too?"

"They appear to be thinking of it," was the reply. "And there on the
margin of the sheets, of each of the sheets, is a date line--Saturday,
April 15th. This is the 13th."

"Is that the date set for the explosion?" asked the boy, with wide-open
eyes.

"I don't know," was the reply, "but it seems to me that we ought to get
out of here and communicate with Lieutenant Gordon, and also with Mr.
Shaw, in New York. The date marked here may be the one set for action."

They started at once for the door, Ned taking the sheets with him and
hoping to pass the guard without being seen. As they moved forward,
however, they heard voices, and then a square of light told them that the
door which they had left closed had been opened, and that three men were
entering.

"If they turn on the light now," Jimmie whispered in Ned's ear, "there'll
be somethin' doin' here."

The newcomers did not light the flaring torches with which the room was
usually illuminated, but, closing the door, sat down near the forge.

"I think," Ned whispered, drawing Jimmie toward the door, "that the fate
of the Gatun dam and the _Daily Planet_ building depends on our getting
out of here. Move carefully."

CHAPTER IX.

A FASTING STUNT IS SUGGESTED.

While Ned and Jimmie were wondering how they were to escape from the
subterranean chamber, Frank Shaw sat in the private room in the old house
on the road to the Culebra cut, facing the gentleman of military carriage
and wondering what would be the next move in the complicated game.

"How long have you known Lieutenant Gordon?" the man asked. "I beg your
pardon," he said, without giving the boy opportunity to answer the
question, "but I have not yet told you who I am, and you can hardly be
expected to answer questions asked by an unknown person, especially when
so much is at stake. I am Colonel Sharrow, of the United States army,
detailed on Canal Zone duty."

The man's manners were frank and engaging, his personal appearance that of
an officer in the service, yet Frank did not tru