364 EXPLANATION OF THE PLATES. 



PLATE VI. 

 The view in Plate 6, represents a very common feature in the slate and thin-bedded sandstone hills, 

 where the Erie division of the New- York rocks prevails. Onestagra is upon the left, and is a 

 steep escarpment of the Hamilton group. The Catskill division appears in the distance. The hills 

 are usually steep, and furnish a scanty pasturage. It is a view in Fultonham, Schoharie county. 



PLATE VII. . 



This is a view of the Catskill range, as it appears upon the high ground opposite the landing at Catskill. 

 The foreground is occupied by the taconic slate; the middle by the Hudson river series, which are 

 much disturbed, but which finally pass beneath the thin-bedded calcareous shale of the waterlimes. 

 The back ground is occupied by the Catskill division, which exhibits many red and green strata, 

 with their slates intervening, but rarely contains fossils The New-York system is here crowded 

 into a very narrow space, and dips rapidly beneath the Catskill mountains. The base of the 

 mountains is gained by passing over a succession of narrow terraces. The mountains themselves 

 are deeply cleft by the northern diluvial current, which must have pressed with gTeat force and 

 power upon the most advanced of the outlying hills of the Catskill. It is at this point that this 

 great current, with its burthen of stones, is deflected to the east. 



PLATE VIII. 



Is designed to give a semi-panoramic view of the valley and hills of the Schoharie. The middle of the 

 back qround is formed of the Helderberg division, mainly : at the junction of the valley with the 

 hills the Hudson river group ceases, and the Helderberg division begins. The Ontario division is 

 also unknown here, or may, perhaps, be feebly represented by a series of thin-bedded dark colored 

 shales. At the west, beyond the main bluff, the Cobleskill enters into the valley of Schoharie. 

 The Erie division appears upon the left, and the Champlain upon the right The vallies and hill- 

 sides are valuable and productive lands. 



PLATE IX. 

 The Genesee river, at and below Rochester falls, has excavated a deep channel in the soft shales for a 

 considerable distance below the city. As usual, however, the hard bands of rock resist the process 

 of excavation until they are undermined, when they fall of their own weight, or yield to the pressure 

 of circumstances. These hard bands, however, create cascades and water-falls more or less im- 

 posing. Two falls are thus created at or near Rochester, and are usually known as the Upper 

 and Lower falls. The view is that of the Upper falls. The hard band in this instance is the 

 zara limestone, and the thin band calcareous layers immediately below it. The view was 

 taken on the east side, at the turn in the pathway about eighty rods below the falls. 



PLATE X. 



The American falls are seen to the best advantage upon the Canada side. We look down upon the 

 deep gulf, occupied by forest trees of many kinds, beyond which the cataract appears. The geolo- 

 gical formations belong to the Ontario division. 



PLATE XI. 



On the west side of the creek at Schoharie the Catskill range rises in the distance, and at the south. 

 The meadows and flats appear immediately beneath the foreground, and the creek bathing the base 

 of the western hills. 



