“Run,” cried Alan. “If we can get into the passage beyond we may be able to block up the way and prevent it coming through after us.”
They reached the narrow opening, and all around were huge blocks of rock and stone which they piled up one on top of the other.
“Only one more is needed,” cried Alan triumphantly. But he spoke too soon—a large, flat head, perhaps a foot and a half in length, with ugly eyes glowing like live fire, shot through the opening, and watched them. The mouth was open wide and the forked tongue shot rapidly in and out in venomous fury. The smell was terrible, whether from its breath or permeating through its skin from its body, they could not tell, but it made them feel giddy, sick and ill. For perhaps ten minutes (if time could be measured in that awful place) it remained there motionless, and then gradually the stones came tumbling down as it forced its way through the barricade.
The boys watched their horrible foe. They were powerless. Escape was impossible, for behind them was a narrow passage, perhaps a mile in length, that offered no shelter.
Would it never attack them? Why keep them in this awful suspense?
“Knife,” came suddenly from between Alan’s tightly compressed lips. Then after a moment, during which time he opened the well worn blade—“There are plenty of stones behind?”
“Plenty.”
Swiftly followed the instructions. “Pick up the largest you can handle—both of you—when I give the word dash them at the brute’s head. It is our only chance—then rush past the head.”
“But—” commenced Desmond.
“Don’t argue—it’s our only hope. The thing is too big to turn round in this small space. It must go on. Once we get past it we may stand a chance.”