title="33"/> reply, “and rested there a few hours. Jimmie had to eat there, of course!”

“Eat!” came the boy’s voice from the fire. “If I ever get a bite at food again it will drop down into the toes of me shoes! Here!” he shouted, as Pat produced a can of pork and beans and started to open it. “You needn’t mind opening that! I’ll just swallow it as it is.”

“Bright boy!” laughed Pat, handing him a liberal supply of beans and fried bacon. “Now fill up on that and then loosen up on your impressions of the sky.”

“I thought I’d make an impression on the earth before I got through,” Jimmie mumbled, his mouth full of beans. “We went up so far that the mountains looked like ant hills, didn’t we, Ned?”

“About 7,000 feet,” was the reply. “You see,” he added, turning to Frank, “I wanted to size up the situation before I landed. If there is anybody in this upturned country at all, our presence here is known. The aeroplane’s chatter took good care of that. And, besides, our landing in the night, with the lights going, gave unmistakable evidence of something stirring.”

“I should say so,” Frank agreed.

“And so,” Ned went on, “I wanted to learn if there were people about here, so I might visit them in the morning and put up the bluff of Boy Scouts playing with an aeroplane in the woods. We can’t attempt anything in the mysterious line,” he went on. “We’ve got to be entirely frank about everything except the business we are here on.”

“Well,” Frank said, “we found people here to-day and called on them.”

“What sort of people?”

“Well, they seemed to have good broad backs,” laughed Frank.

“They ran away from you?” asked Ned, in surprise. “I should think they would have proved inquisitive. Where were they?”

“Down by Kintla lake.”

“Indians?” asked Ned.

Then Frank told the story of the visit to the shore of the lake and the cavern, taking good care to describe the surroundings as closely as possible. Ned laughed when the boy came to Jack’s adventure in the hidden chamber.

“I say it is some deserted mine,” Pat declared, when Frank had concluded the recital. “What else could it be?”

“Robber’s nest!” suggested Jack.

Ned remained silent for a moment and then abruptly asked:

“What kind of footwear made those heelless prints?”

“You may search me!” Jack cut in.

“Must have been Indian moccasins,” Frank observed.

Jimmie, who had been standing by the small fire, listening to the talk, now advanced to the little circle about the machine and uttered one word: “Chinks!”

“It is always Chinks with Jimmie,” grinned Frank. “When there is a cyclone in New York the Chinks are to blame for it, if you leave it to him.”

“What would Chinks be doing up here?” demanded Pat.

“Don’t they get gold by washing it out?” asked Jack, with a nudge at Jimmie’s side. “Perhaps they’re going to start a laundry!”

While this chaff was in progress Ned stood looking thoughtfully in the direction of the lake. Not a word did he say regarding the sudden and brief communication Jimmie had presented.

“Any forest fires in sight?” asked Pat, finally breaking the silence.

“Not one,” Jimmie answered. “I would have dropped into one if it had come my way. It was fierce up there!”

“It is rather cool when you get up a couple of miles,” Ned laughed, “and Jimmie wouldn’t listen to reason regarding his clothes. To-morrow I’ll give one of you boys a ride, and you may see for yourself.”

“Not me!” Pat exclaimed. “I’ll stay below and help pick up the pieces.”

“I should like to go,” Frank said. “We may find the people we saw in the rowboat. When we become acquainted with them we may be able to learn something about that cavern.”

“I would advise remaining silent about the cavern,” Ned said. “It may be used for some criminal purpose, and we must not admit that we know of its existence. We are just carefree lads, here for an outing, remember,” he added, with a laugh, “and we are due to make friends with everybody we come across.”

“But you made us lug all this camping outfit up here,” complained Jack, “so the men who steered the burros up the hills wouldn’t know where we camped. What about that?”

“I thought it best to cut off all communication with the people below,” explained Ned. “It may be that the purpose of our visit here is suspected. In that case some one from below might want to find us—for no good purpose. So we’ll keep out of sight of the people in the towns, unless they see our aeroplane, and cultivate the acquaintance of the natives—if there are any.”

“How about gasoline and provisions?” asked Pat.

“I have plenty of gasoline stored on the right of way of the Great Northern railroad,” Ned replied, “enough to last us a month. It was piped into a hidden tank from an oil car by a train crew now out of the state. We are to get provisions at the same place, if we need more, for Uncle Sam fixed all the details for us. All we have to do is to find the fellows who are setting forest fires and bring them to punishment.”

“We ought to locate every little smudge, with that aeroplane,” Frank suggested.

“That is my idea,” Ned replied. “Have you been keeping a good lookout on the lake since you left it?” he added, turning to Pat.

“Some one of us has had eyes on it every minute,” was the satisfactory reply. “No one has returned, I’m sure.”

“You’re not thinking of going there to-night, are you?” asked Jack, with a slight shiver. “I wouldn’t go in there again, even in broad daylight, for a million dollars!”

“Pat is afraid of the sky, and Jack is afraid of the bowels of the earth!” laughed Frank. “We’ll have to tuck them both in bed before we can accomplish anything.”

“You may all go to bed but one,” Ned said, looking about the group, his eyes finally resting with a significant look on Frank’s excited face. “I want to look through that cavern before anything is taken out of it.”

Frank, knowing the meaning of the look he had received, went to his little tent for his revolver and his electric searchlight and was soon ready for the expedition. Jimmie looked sulky for a moment at being left out of the game, then his face brightened and he crawled into the tent that had been prepared for Nestor and himself and burst into a fit of laughter.

“I’ll show ’em!” he said, stuffing the blanket into his mouth to suppress the sound of his merriment. “I’ll teach ’em to put me in the discard.”

“Any wild animals up here?” asked Ned, as the two started away down the steep declivity.

“Two Black Bears and three Wolves!” called Jimmie, from his tent.

This was a reference to the Boy Scout Patrols to which the boys belonged. Frank and Jack were members of the famous Black Bear Patrol of New York City, while Ned, Pat and Jimmie were members of the Wolf Patrol.

As the lad spoke Frank and Jack broke into growls which might well have come from the throat of the grizzliest grizzly in the Rocky Mountains, while Pat sent forth a wolf howl, which might well have been a signal to the pack.

“You may meet the real thing out here,” warned Ned, turning back to look over the plateau, now shining in the light of a half-moon. “There are both bears and wolves in this region. When you meet them, don’t wait for Boy Scout signs!”

“Oh, we’ll initiate ’em, all right,”