“Well, I guess we don’t have to stand squarely under it,” Dick offered; and with that they moved into the black bore, coming shortly to the heading where the clamor of the air-driven drills made a din like that of a boiler shop.
Living over the events of that terrible morning afterward, they both remembered that it was the ear-splitting noise that drove them back to the tunnel mouth; the noise and the closeness of the air in the heading. As yet, the ventilating fan had not been put in operation—as it would be when the depth grew greater—and the exhaust air from the drills served only to make the air a half-stupefying mixture for anyone coming into it from the out-doors.
For the time the blast firing on the opposite slope had ceased, and above the booming thunder of the river they could hear the chatter and clink of the air drills on the O. C. grade. Just at this point the “enemy” railroad was forced to blast out a long rock cutting to make a shelf for its track, and the firing—with short intervals for drilling and loading the holes—was fairly continuous.
Standing in the mouth of the tunnel and looking outward there was little in sight to betoken the activities going on in the depths of the big bore. Careful for the safety of his men, Mr. Ackerman had billeted the off-shift in a camp lower down the canyon. Thus, save at the shift-changing hours, and at such times as the material train or the spoil train was coming or going, the only outside workers were the man who ran the air-compressor and his fireman.
From their refuge behind the plank bulkhead Larry was once more looking up at the inadequately propped clay roof.
“I’m telling you, Dick, that stuff is plenty dangerous, and it’s getting more so,” he insisted. “If you’ll watch it, you’ll see little bits of the clay crumbling off every now and then. I wish to goodness we could get some timbers up here and place them.”
“So do I,” Dick agreed. “If that roof should take a notion to fall down——”
The sentence wasn’t finished because the breath was lacking wherewith to finish it. As if he had suddenly lost his mind, Larry made a plunging football tackle on his lighter companion, shooting him out between the rails of the track and falling with him. At the same instant there was a sort of grunting rumble behind them, and when they looked back a stifling horror rose up to choke them. In the twinkling of an eye the tunnel mouth had disappeared and its place was occupied by a shelving mound of clay.
“Oh, good mercy!” Dick gasped; “the men—they’ll stifle to death in there! And Mr. Goldrick’s in there with them! What shall we do?”
There was reason enough for the horrified gasp of helplessness. Apart from the two men in the compressor shed there was nobody to call upon; no rescue force available. True, there were the O. C. rock quarriers on the other side of the canyon; but even if they could have been summoned, they had no means of crossing the torrenting river.