These cliffs rise abruptly from the water to the height of 250 and occasionally 300 feet.

They occur first on one side of the river, and then on the other, there being an open or a lightly-timbered flat on the opposite side, with a line of trees almost invariably round it, especially along the river.

These flats are backed, at uncertain distances, by the fossil formation, as by a natural inclosure--sometimes it rises perpendicularly from the flats, but more generally assumes the character of sloping hills.

The cliffs occasionally extend, like a wall, along the river for two or three miles, and look exceedingly well; but their constant recurrence, at length fatigues the eye.

At the point at which we had now arrived this remarkable formation ceases, or, as we are going up the river, I should perhaps be more correct if I said, begins.