CHAPTER XXI.

  PLUNGED UNDER GROUND.

  For two reasons Jerry and Hamp stayed but a short time at theirtemporary camp by the Mallowgash.

  In the first place, Hamp quickly recovered from the chilling effects ofhis bath, and refused to be considered an invalid any longer. In thesecond place, both lads felt a growing uneasiness concerning Brick. Theyhad no tangible suspicions or fears. They were merely anxious toovertake him, since they were, in a measure, responsible for his safety.

  Accordingly, in a little more than an hour after the parting, they wereready to start. They crossed the Mallowgash at the frozen spot, andeasily picked up the trail. The two heavy sleds delayed them somewhat.On the whole, they did not travel quite so rapidly as the other party.As time slipped by, their uneasiness grew upon them. They had expected,ere this, to meet Brick coming back. They were alarmed, too, by thethreatening aspect of the weather.

  Finally they reached the clearing by the stream. Here the short trail ofblood gave them a terrible fright. Their looks meant what their lipswere afraid to utter--the dread word "murder."

  Then Jerry laughed.

  "This is nonsense," he said. "It's nothing to be scared about, Hamp.One of the party fell on the snow and scraped his nose. Look! here'swhere the crust is dented in."

  "That's so," replied Hamp, in a relieved tone. "Cracky! I was scared fora minute."

  "So was I," admitted Jerry. "They must be having a long, hard chase.Still, they can't be much farther ahead."

  "Let's walk faster," urged Hamp. "It's going to snow soon."

  They turned to the right, barely glancing at the ledge of rocks and thebrawling stream. They left the clearing and plunged into the scrub andtimber in the direction of the lake.

  They were moving too rapidly to notice that the imprint of but one pairof snowshoes was ahead of them. As they neared the lake, they struck apitch of rising ground.

  The boys dropped into single file. Hamp preceded, and Jerry followedwith both sleds.

  "I can see a bit of the lake through the trees," said Hamp. "It's notmore than half a mile away. We ought to overtake the party between hereand the shore."

  Just then he struck a slippery pitch of rock and snow, and began to feelhis way very cautiously. Six feet below was a fringe of bushes thatshut off further view.

  Meanwhile Jerry had fallen a little behind. He suddenly observed howslim and indistinct was the trail. He paused at once, and the sledsbacked up against his ankles.

  He bent over and keenly scrutinized the impressions on the snow.

  "Hold on, Hamp," he cried. "Something wrong here. I see the marks ofyour snowshoes and of another pair. By cracky! we've blundered. There'sbeen only one man ahead of us."

  "How can that be?" exclaimed Hamp. "We didn't see any marks branchingoff."

  He was startled by his companion's assertion. He tried to stop, but,unluckily, one foot slipped. He came forcibly down on the snow-crust in asitting posture.

  With a yell of dismay he shot down the slope and plunged through thefringe of bushes. A brief glimpse showed what was below--a circulardepression of glistening snow screwing downward like a funnel, until itended in a jagged black hole of extreme narrowness. The same glimpsemade clear to Hamp that some one had created the depression by breakingthrough the crust of snow and gliding into an underlying cavity ofunknown depth. For a fraction of a second Hamp stuck on the brink. Heclutched vainly at air and snow. Then he shot down the abyss, feetfirst, and vanished through the black fissure at the bottom!

  Jerry heard his companion's horrified cries. He knew that somecatastrophe must have happened. He forgot all about his recentdiscovery, and plunged recklessly forward. The natural result was thatthe sleds banged him violently from the rear. Then came a dizzy dropthrough space, and a collision with something soft, that yelled lustilyin Hamp's familiar tones.

  "I--I couldn't help it," grasped Jerry, as he rolled to one side.

  A second later it was his turn to sing out. A rifle, a haunch ofvenison, and half-a-dozen tin dishes pelted him in quick succession onthe head and shoulders. He looked up with blinking eyes. Then heunderstood what the avalanche meant.

  Ten feet overhead was the gap through which he had fallen. Both sledshad stuck there, and blocked it so completely that only a slim creviceof light was visible. The straps on one of the sleds had broken,allowing part of the contents to fall through.

  Jerry held his breath for an instant, expecting another avalanche. Whennothing more fell, he recovered his presence of mind.

  "That you, Hamp?" he whispered. "Are you hurt?"

  "I don't think so. I fell on a pile of snow."

  "Neither am I," declared Jerry. "It was a lucky escape for both of us. Ihaven't got a bruise."

  "No wonder," replied Hamp, in an injured tone. "You landed right on topof me. I'm just getting my wind back."

  "I'm awfully sorry," said Jerry, "but I couldn't help it."

  "Oh, that's all right. Only if I had known you were coming, I would havecrawled out of the way. Where are we, anyhow?"

  "That's what I want to know," Jerry replied. "It must be a cavern, Hamp.The entrance was on top, and it got snowed over in the big storm."

  "Some one broke through the crust before us," said Hamp, "for I saw themarks as I was falling."

  "Then he's in here now, whoever he is," whispered Jerry, in a startledvoice. "He couldn't have reached the hole to get out."

  There was a moment of terrible silence. The boys huddled close togetherand shivered with fear. Their hearts beat loudly and rapidly.

  "I don't hear anything," whispered Hamp. "Do you?"

  "Not a sound," replied Jerry. "Wait a second. I'll settle the matter."

  He pulled out his metal box of matches and scraped one. As the lightflared up, the lads glanced anxiously around them.

  They saw at once that they were in an underground cavern. To right andleft stretched a gloomy passage, ten feet wide. The sides and roof wereof jagged, slimy rock, dripping with moisture.

  Deep footsteps crossed the snow and led into the yawning blackness tothe right. They were of recent origin, for the white imprint was visiblein half-a-dozen places on the smooth, rocky floor.

  "Do you see that?" Jerry whispered, hoarsely. "There is some personhere, sure enough."

  "Who can it be?" said Hamp. "Perhaps it's Brick."

  In a clear, distinct voice he called the missing lad's name severaltimes. But there was no reply. Jerry shook his head.

  "It's not Brick," he muttered. "How would he get separated from hiscompanions? We were following only one trail toward the last, so thismay be Sparwick."

  "Then why did Brick and those men give up the chase and branch off?"asked Hamp. "It's too deep a mystery for me."

  "It is sort of puzzling," admitted Jerry, "but we won't bother aboutthat now. Whoever it was that fell into the cavern, I believe he hasfound a way out by this time, and that's the first thing we want to do."

  "I hate the idea of crawling through the dark," muttered Hamp.

  "The matches will last if we use them sparingly," Jerry replied. "We'vegot to take this stuff with us, though. No; we'll leave the venisonbehind. Here's the rifle. Be careful, for it's loaded."

  He gave Hamp the weapon and some of the dishes. The rest he tookhimself. When he picked up the tin coffeepot, it rattled. He lifted thelid, and found two sperm candles.

  "Here's luck," he exclaimed. "How did they get here? We're sure of lightnow."

  "Brick put them in the coffeepot this morning," said Hamp. "He had themin his pocket, and didn't want to carry them."

  "Brick ought to have a medal for that," declared Jerry, as he lightedone of the candles. "Have we got everything? Yes; come on."

  They trampled over the snow and went cautiously and slowly along thegloomy passage. The yellow gleam of the candle danced ahead of them andthrew grotesque shadows on the slimy walls and roof. They advanced tenfeet. The distance increased to t
wenty. As yet, not a speck ofdaylight could be seen.

  Suddenly a rustling noise was heard. A low, angry growl followedinstantly. Beyond the radius of candlelight the terrified boys saw apair of fiery, snapping eyes. They stopped and turned half around.

  "The rifle, quick!" cried Jerry.

  He snatched it out of his companion's hands and gave him the candleinstead. But before Jerry could lift the hammer of the weapon astartling interruption came from an unexpected quarter.