"What—-what is it?" roared the Professor.
"We're struck!" shouted Tad.
"Lie still. Hug the wall!" bellowed the stentorian voice of Jim Nance, who himself had crept closer to the Canyon wall and lay hugging it tightly.
The deafening, terrifying reports continued. One corner of the ledge over their heads split off, sending a volley of stones showering over them, leaving the faces of some of the party flecked with blood where the jagged particles had cut into their flesh.
It was a terrible moment for the Pony Rider Boys.
CHAPTER X
ESCAPE IS WHOLLY CUT OFF
Not one could collect his thoughts sufficiently to reason out what had taken place. The guide, however, had known from the first. He feared that his charges would be killed, but there was nothing more that he could do.
The bombarding continued, some explosions sounding near at hand, others further down or up the Canyon, but each of sufficient force to send shivers up and down the spines of the Pony Rider Boys. They never had experienced anything approaching this.
"I'm going to stand up," declared Tad, rising to his feet. "I won't be killed any quicker standing than lying down. Besides, I don't like to shirk."