For five and three quarter miles these rocks rise perpendicularly from the water's edge to the height of nearly twelve hundred feet.

They are composed of a black granite near their base, but from the lighter color above, and from the fragments, we suppose the upper part to be flint of a yellowish brown and cream color.
"Nothing can be imagined more tremendous than the frowning darkness of these rocks, which project over the river and menace us with destruction.

The river, one hundred and fifty yards in width, seems to have forced its channel down this solid mass; but so reluctantly has it given way, that during the whole distance the water is very deep even at the edges, and for the first three miles there is not a spot, except one of a few yards, in which a man could stand between the water and the towering perpendicular of the mountain.

The convulsion of the passage must have been terrible, since at its outlet there are vast columns of rock torn from the mountain, which are strewed on both sides of the river, the trophies, as it were, of its victory.

Several fine springs burst out from the chasms of the rock, and contribute to increase the river, which has a strong current, but, very fortunately, we were able to overcome it with our oars, since it would have been impossible to use either the cord or the pole.