The moment the mischief (for such it was, in nearly every instance) was done, he would suffer greatly in dread of being found out.  But to-night, as on the occasion of the daylight stop in the canon, he had no warning, no opportunity to check himself, nor any desire to do so.  In each instance he had heard, dozing in the day-coach and sleeping soundly in his berth, the voice cry:  “John!  John!” and instantly his brain was ablaze with the light of burning wreckage.  In the canon he had only felt, indefinitely, the danger ahead; but to-night he saw the bridge swept away, and the dark gorge that yawned in front of them.  Instantly upon hearing the cry that woke him, he saw it all.

“When I realized that the train was still moving, that my first effort to stop had failed, I flung these strong men from me with the greatest ease.  I’m sure I should have burst those steel bands that bound my wrists if it had been necessary.

“Thank God it’s all over.  I feel now that I am cured,—­that I can settle down contented.”

The man drew a handkerchief from his pocket and wiped his forehead, keeping his face to the window for a long time.

* * * * *

When the conductor went forward, he found that it was as the porter had pictured.  The high bridge had been carried away by a water-spout; and on the edge of the opening the engine trembled, her pilot pointing out over the black abyss.

McNally, having driven his fireman from the deck, stood in the cab gripping the air-lever and watching the pump.  At that time we used what is technically known as “straight air”; so that if the pump stopped the air played out.

The conductor ordered the passengers to leave the train.

The rain had ceased, but the lightning was still playing about the summit of the range, and when it flashed, those who had gone forward saw McNally standing at his open window, looking as grand and heroic as the captain on the bridge of his sinking ship.

A nervous and somewhat thoughtless person came close under the cab to ask the engineer why he didn’t back up.

There was no answer.  McNally thought it must be obvious to a man with the intelligence of an oyster, that to release the brakes would be to let the heavy train shove him over the bank, even if his engine had the power to back up, which she had not.

The trainmen were working quietly, but very effectively, unloading.  The day coaches had been emptied, the hand-brakes set, and all the wheels blocked with links and pins and stones, when the link between the engine and the mail-car snapped and the engine moved forward.

McNally heard the snap and felt her going, leaped from the window, caught and held a scrub cedar that grew in a rock crevice, and saw his black steed plunge down the dark canon, a sheer two thousand feet.