He had taught them to live upon the simplest food; and the knowledge of practical botany which he had imparted to them--more particularly to Lucien--would enable them, in case of need, to draw sustenance from plants and trees, from roots and fruits--to find resources where ignorant men might starve.

They knew how to kindle a fire without either flint, steel, or detonating powder.

They could discover their direction without a compass--from the rocks, and the trees, and the signs of the heavens; and, in addition to all, they had been taught, as far as was then known, the geography of that vast wilderness that stretched from their own home to the far shores of the Pacific Ocean.
The Colonel knew that he might safely trust them upon the prairies; and, in truth, it was with a feeling of pride, rather than anxiety, that he consented to the expedition.

But there was still another motive that influenced him--perhaps the most powerful of all.

He was inspired by the pride of the naturalist.