"Aw, cut it out!" advised Will. "Are you boys all safe?"

"Sure we're all safe!" answered Sandy, "George has a grouch because he hasn't anything to eat here, but the rest of us are all right!"

"Where's Bert?" asked Frank.

"In here!" was the answer.

"We brought a surgeon for him," Frank went on.

"He doesn't need a surgeon now!" replied George. "What he needs more than anything else is a cook!"

"We'll give him two cooks!" shouted Tommy.

"Why don't you hurry up and get us out?" demanded Bert, in a weak voice.

"If you remain in there a few weeks," Tommy laughed, "perhaps you'll get so thin you can crawl out of this crack!"

"Well, get to digging!" replied George.

"And for the love of Mike," exclaimed Sandy, "when you get to digging, don't drop any rocks on top of us! We have a little hole here now about four feet square!"

After making a study of the situation and advising with Doctor Pelton as to the proper course to pursue, the boys began prying at a large rock which lay almost on top of the shelf upon which the boys had ridden to the thicket. The rock moved, but grudgingly.

"If you can move that rock," the doctor said, "I think the one just above it will slide down and leave an opening large enough for the boys to pa.s.s out of. It ought not to be much trouble to move it!"

Notwithstanding the doctor's predictions, the boys worked at the rock with their home-made handspikes for an hour before it broke loose and rattled down upon the shelf just above the fire.

"Come out of that now," cried Tommy stooping down and looking into the cavern. "Come on out, now!"

Sandy was not long in obeying instructions. George came next and then the two lads turned about and lifted Bert out of his cramped position.

"That pigeon hole we've been occupying is about four inches square!"

Sandy declared. "And I'm just about dead for a good long breath of fresh air! I never knew before how good air tasted."

Bert glanced around the circle of faces and smiled amusedly as he saw that his chum was there with the rest.

"Where'd you go, Frank?" he asked.

Frank hastened to the lad's side and bent over him.

"I headed for the cabin," he answered, "and missed it. The Indian smoke signal brought the boys out and they fed me up."

Will now approached the spot where the two boys were talking and pointed to Cameron and Fenton now sitting with their faces illuminated by the blaze. They both scowled at the inspection.

"Which one of those men gave you the clout on the head?" Will asked.

"That fellow with the alfalfas," replied Bert.

"And he stole the code message you were carrying?"

"I don't know!" replied Bert. "I had it when he came into the cabin and began talking with me and I haven't thought of it since. Was it stolen?"

"You bet it was!" replied Frank. "But we've been to Cordova and got a duplicate of it!"

Cameron and Fenton scowled fiercely as they listened to the conversation.

"Have you got the code message with you now?" asked Will.

"Sure I have!" answered Frank.

"Suppose you read it, then."

Frank took an envelope from his pocket, tore off one end, and brought out an ordinary sheet of letter paper bearing the heading of the wireless company. The boys gathered about him eagerly.

"It isn't very much!" Frank said with a laugh. "Say, you two fellows,"

he added, waving the paper in the direction of Cameron and Fenton, "would, you like to hear this code despatch read?"

"You bet they would," cut in Sandy. "That's all they've been thinking about for the last two days!"

"Well, it's short and sweet and very satisfying!" Frank laughed.

"Aw, read it!" demanded Tommy. "What's the use of making a monkey of yourself? Let's see what it has to say for itself."

Frank bent a searchlight on the paper and read:

"Will Smith, in camp near Katalla, Alaska: The machine plans have been traced to the cabin to which you were directed. Make close examination there before looking elsewhere. Horton."

"What do you know about that, Cameron?" asked Will with a smile. "Are the plans really hidden in our cabin?"

"Your cabin!" sneered Cameron.

"I guess the cabin belongs to us as much as it does to you!" Tommy cut in. "Are the machine plans hidden there?"

"What do you want of the machine plans?" demanded Cameron.

"They don't belong to you!" roared Fenton.

"We have no claim upon them," replied Will. "In fact, we have no use for them at all, except that we want to identify the mark of a human thumb which soiled one of the papers."

"All lies!" shouted Cameron.

"I'm telling you the truth," declared Will.

"Then why didn't you come right to me and say so?" demanded Cameron.

"You didn't give us a chance!" replied Will.

"Are the plans hidden in the cabin?" asked Sandy.