310 GEOLOGY OF THE SECOND DISTRICT. 



it. Hence it appears to have been formed by a partial uplift, sufficient to fracture the strata, 

 and give them a slight inclination to tlie north and south. At the present time, however, no 

 causes are in operation sufficiently powerful to remove the broken masses from a gorge of this 

 description. At Keeseville and Cadyville, large rivers, the Ausable at the former and Sara- 

 nac at the latter, still occupy these gorges as their channels, and have sufficient force and 

 power to sweep out, especially in the time of high water, all rocks of an ordinary size. At 

 this place there is merely a small rill discharging itself from a small lake of dead water, in- 

 sufficient in itself to accomplish any perceptible change. To account for the present condi- 

 tion of this rock, we have therefore to go back to a period when some current swept through 

 this gorge with great force and power ; for, by no other means could the materials, whicii 

 once filled the space between the present walls of the gulf, be removed. 



In Cadyville is another gorge of this description, but its width, is much less. Tt is a mile 

 and a half long. The Saranac flows through it, and it has a fall of forty or fifty feet. It has 

 an average width of fifty, and a depth varying from twenty to thirty feet. The force which 

 produced this separation operated with the greatest power at the east end, where the rock is 

 broken and displaced, and the gap is from eighty to a hundred yards wide. 



Other instances of fractures and of fissures occur in this rock, though none so large as those 

 already given. From these facts, it seems that this rock has suffered more from agents cal- 

 culated to produce these effects, than many others apparently equally exposed. 



FucoiDAL Layers. 



Three miles from Cliazy towards Lawrence's corners, near the highway, the fucoidal layers 

 are remarkably well characterized. Tlie rock is a bluish shale, intermixed with some quartz ; 

 but the materials were soft and fine, and hence the vegetables appear clearly defined, though 

 too much enveloped in what must have been a mud, to show their specific marks. The mass 

 is ten feet thick, and is a complete matting of fiicoids. From this mass of vegetables there 

 is a sudden passage to one filled with encrinal remains, together with Strophomena and Orthis. 

 As this was not observed at any other locality in Clinton, I am unable to determine whether 

 it is more than a local arrangement ; and as the fucoidal mass is not sufficiently elevated to 

 disclose what is beneath, I am unable to satisfy myself of their true position. About half a 

 mile west, on a small stream, they appear in their usual form, passing into the potsdam sand- 

 stone below. No fossil is ever associated in these masses of fucoids ; they seem to have 

 excluded every thing else, and to have formed a surface not well adapted to the habits of 

 marine animals. / 



CALCirEROUS Sandrock. 

 This is composed of 

 1. A mixture of calcareous and siliceous particles, forming a rock of a yellowish brown color, in which 

 calcareous spar forms a constituent part. It is always granular. It is too earthy to receive a polish. 

 A few fossils make their appearance in the upper part of this mass. 



