Then it tried to pound off the cylinder. The flying arms next took the roof supports, snapping them like pipe stems, and buried the fireman in a heap of debris.

“Jump!” gasped Roberts.

“I stay,” breathed Ralph.

And, stripped of everything except her cylinder, No. 93 dashed on--a wreck.

[CHAPTER XVI—THE WRECK]

The battered locomotive continued its course for nearly half a mile, with engineer and fireman crouching back on the coal of the tender. There was a diversion of the circling driving rod as the pace slackened.

Then a violent hissing sound told of a leak somewhere in the machinery. The great steel locomotive slowed down like a crippled giant.

“She’s dead,” said Roberts, choking a queer sound way down in his throat. “Old 93!”

Ralph jumped to the ground and the fireman after him. The latter went all around the stalled locomotive, shaking his head mournfully.

Ralph hastened ahead out of the glare of the headlight and peered down the rails. For nearly two minutes he stood, shading his eyes with one hand to bring the disappearing runaway within focus. The wild engine had sped on its way untrammeled. He made out that she had slowed up. In the distance he fancied he saw a brisk form spring from the cab. Ralph figured it out that a switch had been set.