“What will they try next?” queried Adair, when the suspense was again growing intolerable.

“It is simple enough, if they happen to think of it,” was Ford’s rejoinder.  “A few sticks of dynamite in a plugged gas-pipe:  cut your fuse long enough, light it, and throw the thing under the car.  That would settle it.”

Adair yawned sleepily.

“Well, they’ve got all night for the inventive part of it.  There’s no rescue for us unless somebody—­a good husky army of somebodies—­just happens along.”

“The army is less than eight miles away—­over at Frisbie’s camp,” said Ford.  “With Dick to lead them, the track-layers would sack this place in about five minutes.  If I could only get to the wire!”

Brissac heard the “if.”

“Let me try to run their picket line, Ford,” he said eagerly.  “If I can get around to our quarters and into the telegraph tent—­”

“You couldn’t do it, Roy.  There is the proof of it,” pointing to the body of the slain negro.  “But I have been thinking of another scheme.  The track-camp wire is bracketed across the yard on the light-poles.  I have my pocket relay.  I wonder if we could manage to cut in on that wire?”

“Wait a minute,” Brissac interrupted.  He was gone but a moment, and when he returned he brought hope with him.

“The wire is down and lying across the front vestibule,” he announced excitedly.  “They must have cut it up yonder by the telegraph tent and the slack has sagged down this way.”

“Which gives us a dead wire without any batteries,” said Ford gloomily; and then:  “Hold on—­aren’t there electric call-bells in this car, Adair?”

“Yes, several of them; one in each state-room.”

“Good! that means batteries of some sort,” said Ford.  “Rummage for them, Brissac, while I get that wire in here.”

The wire was successfully pulled in through the front vestibule without giving the alarm.  Ford twisted it in two when he had enough of it to reach the central compartment.  Adair did sentry duty while the two technicians wrought swiftly.  The bell battery was found, the ground connection made with a bit of copper wire stripped from one of the state-rooms, and Ford quickly adjusted the delicate spring of the tiny field relay.

What he feared most was that the few dry-cells of the bell battery would not supply the current for the eight miles of line up Horse Creek.  For a time, which lengthened to dragging minutes, the anxious experimenters hung over the tiny field instrument.  The sensitive magnet seemed wholly dead.  Then, suddenly, it began to tick hesitantly in response to Ford’s tapping of the key.

“Thank God, the battery is strong enough,” he exclaimed.  “Now, if there is somebody within hearing at Frisbie’s end of the line ...”

He was clicking persistently and patiently, “E-T,” “E-T,” “E-T,” alternating now and then with the Horse Creek call and his own private code letter, when Adair came up from his post at one of the rear windows.  The golden youth was the bearer of tidings, but Ford held up his hand for silence:  some one was breaking in to reply from Frisbie’s—­Frisbie, himself, as the minimized tickings speedily announced.