He started to follow the fleeing laborers when a mass of muddy earth came slipping down a dozen yards in front of him. It blocked the shelf upon which he had climbed, and he checked himself, gazing confusedly up the slope. A large part of the overhanging hill-side appeared to be in sluggish motion. The wet, red soil far up toward the top of the cut had begun to slide as if it were being pushed into the bed of the canal by some unseen force. Dislodged fragments of rock rolled down the surface of the slide and clattered in advance of it, but so deliberate was the movement of the mass that there seemed to be time enough to escape it. Walter ran along the ties and began to plough knee-deep through the impeding heap of muddy tenacious clay on the track. He glanced upward again, halted irresolutely, and gasped aloud: "Great Scott, here comes a whole train of cars falling downhill." The landslide had started just beneath the uppermost shelf of excavated rock, and the line of track supported thereupon was almost instantly undermined. The rails tilted and slipped with their weight of rock-laden cars before the engine could drag them clear. The train crew jumped and managed to crawl to the firm ground at the crest of the slope a moment before the flat-cars toppled over and broke loose from their couplings. Then the cars hung for an instant, spilled their burden of rock, which made a little avalanche of its own, and rolled down the slope with a prodigious clatter. At this new peril, Walter knew not which way to turn. He could not be blamed for losing his presence of mind. The cars parted company, taking erratic courses, tumbling end over end. One of them bounded off at a slant to fall in front of him, while another was booming down to menace his retreat. All this was a matter of seconds, precious time that was wasted for lack of decision. Instead of making a wild dash in one direction or the other, Walter danced up and down in the same spot, his eyes fairly popping from his head. The result was that, by a miracle of good fortune, the flat-cars roared and rattled past on either side and left him unscathed. Then the huge, loosened layer of earth, moving with lazy momentum, filled the ledge on which he stood, brushed him off, and carried him down the slope. To his amazement he was not wholly buried, but rolled over and over, now on the surface, now struggling in a sticky smother of stuff that held him like a fly in a bed of mortar. A projecting stratum of rock, not yet blasted away, checked the leisurely progress of the mass before it reached the bottom of the cut. Plastered with mud from his hair to his heels, bleeding from a dozen scratches, his clothes in rags, Walter was quite astonished to find himself alive. He was stuck fast in clay almost to the waist and so dazed and breathless that he was unable to call for help.