352 ALTERATIONS MADE SINCE 



that I should not write any thing about it, did it not ap- 

 pear to me that the great chasm which the water has form- 

 ed in the rocks at that place, discloses much of the mine- 

 ralogy of the region, and assists in forming correct 

 opinions concerning the geology of this section of the 

 globe. The delineation by Mr. Weld is reputable to 

 him ; and his pages and illustrations instructive. The 

 account by Mr. Volney is intelligent ; and his plans per- 

 spicuous. The paintings and prints of Mr. Vanderlyn, 

 are pieces which present to the eye, all that can be ex- 

 pected from landscape. The description of Mr. M'Kin- 

 nen, although it is almost as much a picture of his own 

 emotions as of the scenes around him, is nevertheless in- 

 genious and interesting. 



On exploring the strata laid bare by the cataract, their 

 argillaceous, calcarious and siliceous character immedi- 

 ately struck me. I was careful to bring away specimens 

 of each; and these, at all times and distances, enable me 

 to substantiate my own description of the grand falls. 



The lowest of the strata as yet reached, is the rock 

 called by geologists old red sandstone. It is composed 

 of quartzy particles, with a cement of clay and iron. 

 The latter being in the form of reddish brown oxyd, im- 

 parts its colour to the rock. Below the ridge which 

 crosses the stream at Lewistown and Queenstown, the 

 layers of this ancient sandstone make their appearance. 

 It, in all probability, underlays the slate, limestone, and 

 soil, to a great extent. 



The next layers of earthy matter at the falls are com- 

 posed of slate, or shistus. This is very friable, and crack- 

 ed into numberless pieces. It has so little cohesion that 

 the fragments can be easily picked out by the fingers. 



