The primeval forest clothed the whole earth, and the war to which Harry was going seemed a faint and far thing.
Traveling now became slow, because they always had a strong current to fight.

Harry, at times when the country was not too rough, left the boat and walked along the bank.

He could go thus for miles without feeling any weariness.

Naturally very strong, he did not realize how much his work at the oar was increasing his power.

The thin vital air of the mountains flowed through his lungs, and when Jarvis sang, as he did so often, he felt that he could lift up his feet and march as if to the beat of a drum.
They left the fork of the Kentucky at last and rowed up one of the deep and narrow mountain creeks.