"Can we see much of the trail, if we go over with the pack train?" asked
Rob.

"Not so very much," said Billy. "Even the old road is wiped out, now
that the railroad has come. In some places you can find where the trail
once ran, or is supposed to have run, but you have to go by the general
landmarks now.

"When you come to the central ridge beyond old Ellis, you get the last
summit between here and Yellowstone waters. The tunnel runs under that
now. The railroad books say that is fifty-five hundred and sixty-five
feet--the highest of the three northern transcontinental passes.

"So you can figure now, I reckon," he concluded, "that you are mighty
near at the head of the Gallatin, a day's march from here. And if you
want to, you can take the railroad in town, all the way down the
Yellowstone and clean on home to Chicago or St. Louis, without getting
off the cars."

"Well, since we are so near the end of the trail, young gentlemen,"
began Uncle Dick, at this point, "what do you say we ought to do?"

"Well, the first thing we ought to do," said John, "before we go home,
is not to leave all those people out in the wilderness. We have got
Clark and eleven people here on the Gallatin, and Captain Lewis is away
up on the Marias, and Gass and Ordway are scattered every which way
between here and the Great Falls."

"All right, all right!" rejoined Uncle Dick. "Get out your _Journal_
now, and we will see what became of Captain Lewis. We won't follow him
day by day, and we will just take up his trail somewhere near Missoula.

"See here, now. He must have crossed what is called Clark's Fork--all of
that river, part of which is called Hell Gate River, ought to be called
after Clark. He went up the Hell Gate River, without any guides, but he
must have struck an Indian trail which led him over east. On the fourth
day, that is on July 7th, he reached the pass which is called even now
Lewis and Clark's Pass--the only pass named after either of those
explorers, although only one of them ever saw it.

"Now, you see, they were opposite the headwaters of the Dearborn
River--the same stream where Clark left the boats and went up the river
on foot when they were going west the preceding year. They knew where
they were when they got here, and felt pretty fairly safe.

"But Lewis wanted to see about that country north of the Great Falls.
They were now among the buffalo once more and glad enough to find them.
They hunted down the Sun