Niagara Falls, N. Y. August 9-1911. Great Boye Route. Whirlport Rapids. The upper 10 feet of the Medina is mainly sandstone in beds from 6" to 78" with sandy shale parting. All are more or less cross bedded. Then about 2 feet of very thin bedded sandy shales with their local lenses (up to 3") of sandstone. It is in the lower half of this zone that occurs the bottom Chunnings described yesterday. The films form a sandstone from 6" to 78" that gray hard rock. Below there is more of the thin bedded red and sandy shale. The Medina sedimentation is very irregular for within a few hundred feet all or nearly is changed from sandstone to sandy shale. The dear beds of sandstone in the shales are the most changeable. Towards the top the tendency is toward all sandstone as if the deposits of a retreating sea. Basal sandstone. At the base of the