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certain cases, these terms are mutually conver- 

 tible. It is not the less necessary to retain this 

 distinction; as there are some modifications of 

 fracture where no proper differences of texture 

 are perceptible. 



There are two distinct classes of fracture, the 

 large and the small ; and it is the latter which is 

 more especially connected with the texture of a 

 rock. 



EVEN. 



In the even fracture, the surface is a plane of 

 greater or less extent ; without, or with, a very 

 slight degree of curvature. 



UNEVEN, 



When one plane surface is very limited, and 

 succeeded by other planes variously inclined, the 

 fracture becomes uneven, and the angles formed 

 by the meetings of these planes, produce eleva- 

 tions and depressions. It is obvious, that a frac- 

 ture minutely uneven, with considerable eleva- 

 tions and depressions, becomes granular, and 

 may thus be ranked under the head of Texture. 



