f that," spoke up the Professor. "I heard Mr. Darwood say
they were going out the Chilkoot Pass for a short distance, from which
they might branch off."

Tad chuckled softly.

"Why do you laugh?" demanded the Professor.

"Oh, I was just thinking of something funny."

"Let's hear it," begged Stacy.

"I rather think I'll keep it to myself," answered Tad, smiling. "Let
Stacy tell you one of his funny stories."

"All right, I'll tell you one," agreed Chunky readily.

"Leave the telling until you get to camp," advised the Professor. "This
is a rough trail, and you need to give it your undivided attention."

"The Professor is right. We would do well to watch out where we are
going," agreed Tad.

"Yes, I dread to think what would happen to our packs were one of those
mules, in a moment of forgetfulness, to think he was traveling in a
circle at the end of a sweep down in a mine," said Ned.

The trail they were now following was narrow. In fact, it was a mere
gash in the side of the mountain, winding in and out with many a sharp
turn, and there was barely room for the ponies to travel in single file.
Above them towered the mountains for thousands of feet. Below them was a
sheer precipice of fully two hundred feet, getting deeper all the time,
as they continued on a gradual ascent.

"I don't think I should like to be the post rider on this trail,"
decided Ned, gazing wide-eyed at the abyss.

"Especially on a dark night," added Tad.

"Or any other kind of a night," piped the fat boy.

"Oh, I don't know about that," answered Walter. "On a dark night you
couldn't see the gorge. What we don't know doesn't hurt us, eh?"

"There is some logic in that," agreed the Professor.

Professor Zepplin was leading the way, dragging one mule after him at
the end of a rope. Then came Ned with the second pack mule, followed by
Tad and the other two boys. Butler wanted to follow behind the mules so
as to keep watch of them, he not feeling any too great confidence in the
worn-out old animals.

The Professor halted at a turning-out place, where the rocks had been
worn out by the wash of a mountain stream sufficiently wide to enable
two horses to meet and pass by a tight pinch.

"Young gentlemen, this is a wonderful country," he said.

"It's kind of hilly," admitted Stacy.

"In the Indian tongue, Alaska means 'the great country,'" added the
Professor.

"Why, I didn't know you talked Indian," cried Ned.

"I always suspected t