most solid rock. Walking was very rough, and they could not tell how
far the cave extended or in what direction.

"I am going to call again," said Roger, and going back to the mouth of
the cave they set up as strong a cry as before. At first they fancied
somebody answered them, but then all became silent.

"Nothing doing," murmured the senator's son, and his face took on a
look of deep anxiety. "Dave----" He stopped short.

"What?"

"Nothing, only--do you really think the others were killed?"

"Let us hope not," was Dave's grave reply.

CHAPTER XXIII

LEFT IN THE DARK

The thought that their two companions might possibly have been killed by
the toppling over of the sleigh filled Dave and Roger with fresh horror,
and for several minutes neither of the youths spoke. They listened for
some sound, but none came. Then Roger heaved a deep sigh.

"Perhaps we had better try to climb out," he suggested, timidly.

"I've thought of that, Roger. But what if we slip when we get out? Why,
the bottom of the valley is quarter of a mile further down. I don't want
such a tumble, on top of the one we have already experienced."

"If we ever get out we'll have plenty of news to send home," was the
senator's son's comment.

"True; but let us get out before we think of sending news."

They talked the matter over, and at length concluded to do a little more
exploring of the cave. Dave turned up the pocket lantern as high as
possible, and as he did this Roger took from his pocket a short, strong
cord. "I thought this might come in useful, for tying up our supplies,"
explained the senator's son, "so I brought it from the last house we
stopped at. Tie one end around your waist, Dave, and I will hold fast to
the other end. Then I'll walk behind you, and if you go into a hole----"

"I may drag you behind me," finished Dave.

"No, I'll look out for that,--only be as careful as you can."

"I'll take no more risks than are necessary."

They moved forward slowly and cautiously, first to one side of the
cavern and then to the other. At last they struck what appeared to be a
passageway running parallel to the mountain side.

"Let us follow this," suggested Dave. "It may bring us out somewhere on
the road."

Roger was willing to do anything his chum suggested. It was a hard
journey, over rocks that were sharp and slippery. In some spots they
found a coating of ice and above their heads long icicles hanging from
the roofing.