"You can see where the keel of a canoe has rested in the dirt there.

The trail is ever so faint, but it is unmistakably there. See how it broadens out as it extends backward until it reaches the gravel in the stream."

"Moccasin tracks," grunted the guide.

"Where?" asked Walter, apprehensively.

"There," answered the Indian, pointing up the bank whence they had just come.

The boys looked at each other in wondering silence.

"What do you think is the meaning of the visit, Eagle-eye?" asked the Professor.

The Shawnee shrugged his shoulders.

"Mebby hungry."

"That is a sensible explanation of the visit," decided Professor Zepplin. "What other motive could an Indian have for a visit at that hour? There is no cause for alarm. But I wish if any more hungry ones pay us a visit, they would do so in the day time, so as not to interrupt my sleep."

"And mine," laughed Tad.

"Yah-hum," yawned Stacy, sleepily.

"I told you you weren't awake yet," growled Ned. "Let's all go back to our breakfast."

"I second the motion," laughed the Professor. "We are forgetting all about the inner man. And it is time we were getting on our way if we are to make any great progress to-day."

Anxious to be in the saddle again, the boys bounded up the bank and hastily finished their breakfast. While they were doing so the guide stoically busied himself with packing the cooking kits and loading the pack mules, so that by the time the lads were ready all save their own belongings had been stowed away.

It was the work of a few minutes only to strike their tents, fold blankets and pack their personal belongings. They had now been roughing it long enough so that they had become really expert in the work. And, besides, they had learned to get together a fairly satisfying meal out of not much of anything. They had learned many other things that were to prove useful to them in after years, but which at the time was making little or no impression upon them.

Fairly radiating health and spirits, the boys threw themselves into their saddles with a shout. The guide led the way, leading the mule train, and his pace was so rapid that the pack animals were put to their best to keep up with him. Most of the time he appeared to be dragging the led mule, instead of leading it.

"A wonderful country," breathed the Professor, as they finally came out on a high elevation that gave them a glimpse of the eastern slope of the mountains.

They halted to take in the magnificent view.

"This is what is known as the 'Ozark Uplift,'" the Professor informed them.

"I should call it a downfall," answered Ned, gazing off at the deep gorges and jagged precipices. "Why do you call it that?"

The Professor waxed eloquent.

"From the earliest time, young gentlemen, this region has been subject to uprising or downsinking. In all sections of its area it has experienced the effects of powerful dynamic forces--"

"Dynamite--did they use dynamite to blow the mountains up into such shapes as that?" asked Stacy innocently.

"I said nothing about dynamite. Dynamic was the word I used," replied Professor Zepplin, casting a withering glance at the fat boy.

"Oh," Stacy exclaimed.

"It is therefore called the 'Ozark Uplift.'"

"That is interesting," answered Ned solemnly, though it is doubtful if he understood what the Professor was really talking about.

"There is still another of tremendous import connected with this region. You will all be interested in it," announced the Professor impressively.

The boys gathered about him in a circle, meantime allowing their ponies to nibble at the green leaves.

"Yes," urged Tad.

"The region where is now located the Ozark Uplift is said to have been the first land to appear above the waters of the continental ocean."

"You--you mean--" stammered Ned.

"He means this was the first land to appear above the water when this continent was all an ocean," spoke up Tad, with quick understanding.

Stacy urged his pony further into the circle. His face was flushed and he evidently was filled with some sudden new thought.

"What is it, Master Stacy?" asked the Professor.

"You--you say this was the first land to--"

"Yes, so it has been said."

"Then--then this--then this must have been where the Ark landed,"

exploded the fat boy.

For a few seconds a profound silence greeted this announcement. Then the lads broke out into a shout of laughter. Even Professor Zepplin threw his head back and laughed immoderately.

"I am afraid, my young friend, that the place where the ancient craft ran aground was some distance from this rugged spot--"

"But why not?" persisted the boy.

"In the first place, this continent came to life some time after the event you speak of is supposed to have taken place."

"Oh," muttered the lad.

"And now we had better be pressing on."

"When do we reach the Red Star Mine?" asked Ned.

"You will have to ask Eagle-eye. I don't know."

The Indian, when questioned on this point, said the Red Star Mine lay three suns to the southwest of them.

The country seemed to be getting more rough as they proceeded, and it had now become necessary to move with extreme caution for fear of plunging over one of the many abrupt cliffs that now and then appeared almost under the feet of the advancing train.

But the Indian seemed to feel no concern over these. He merely changed his course, skirting the canyon until a turn in its winding course enabled him to head straight into the southwest again.