“Oho!” reflected the young acting chief engineer, not without a slight shudder.  “Is assassination in the plans of the people behind ’Gene Black’s treachery?  Or is putting me under the sod merely an addition that Black has made for his own pleasure?”

The plotter, still unaware of the eavesdropper, had now turned and was walking down the trail.  He was now so far from camp that he did not need to be soft-footed.

Out of the shadow, after a brief pause, stole Tom Reade.

“If Black is going to meet anyone tonight I’d better be near to the place of meeting.  I might hear something that would teach me just what to do to checkmate the plotters against us.”

For fully half a mile the chase continued.  Two or three times Reade stepped against some slight obstacle in the darkness, making a sound which, he feared, would travel to the ears of Black.  But the latter kept on his way.

Finally ’Gene Black halted where three trees grew in the form of a triangle and threw a dense shadow.  In the same instant the young chief engineer dropped out of sight behind a boulder close to the path.

Black’s low, thrilling whistle sounded.  A night bird’s call answered.  Soon afterwards, another form appeared, and Tom, peering anxiously, was sure that he recognized the man whom he expected to see—–­Bad Pete.

What Tom heard came disjointedly—–­a few words here and there, but enough to set him thinking “at the rate of a mile a minute,” as he told himself.

Up the trail came the pair, after some minutes.  Tom crouched flat behind his boulder.

“Great!  I hope they’ll halt within a few feet and go on talking about the things that I want to hear—–­must hear!” quivered Reade.

It was provoking!  Black and Bad Pete passed so close, yet the only sound from either of them, while within earshot, was a chuckle from Pete.

“That’s right!  Laugh,” gritted disappointed Tom.  “Laughing is in your line!  You’re planning, somehow, to put the big laugh over the whole line of the S.B. & L. railroad.  If I could only hear a little more I might be able to turn the laugh on you!”

The pair went on out of sight.  Tom waited where he was for more than half an hour.

“Now, the coast is surely clear,” thought Reade at last.  He rose and started campward.

“The soft-foot, the rubber shoe won’t work now,” Tom decided.  “If I were to go along as if trying not to run into anyone, and that pair got first sight of me, it would make them suspicious.  I haven’t been eavesdropping—–­oh, no!  I’m merely out taking a night stroll to ease my nerves.”

Therefore the cub chief puckered his lips, emitting a cheery whistling as he trudged along up the trail.

As it happened the pair whom Tom sought had not yet parted.  From behind a boulder a man stepped out in his path.  From the other side of the boulder another man moved in behind him.