In a quarter of an hour he was once more in his dry suit.
He was now two miles below the island, where yesterday the Indians had been concealed, and where this morning Miller had crossed.
Wetzel knew Miller expected to be trailed, and that he would use every art and cunning of woodcraft to elude his pursuers, or to lead them into a death-trap.

Wetzel believed Miller had joined the Indians, who had undoubtedly been waiting for him, or for a signal from him, and that he would use them to ambush the trail.
Therefore Wetzel decided he would try to strike Miller's tracks far west of the river.

He risked a great deal in attempting this because it was possible he might fail to find any trace of the spy.

But Wetzel wasted not one second.

His course was chosen.