142 



acuteness which would result from a recent 

 fracture. Geologists have sometimes distin- 

 guished these varieties by the distinct terms, 

 conglomerate and breccia ; the former also some- 

 times by that of puddingstone ; but these terms 

 not having been always used in the same con- 

 stant sense, no advantage has arisen from them. 



In many examples of the aggregate structure, 

 sharp and rounded fragments are united in the 

 same mass. 



In certain cases, a rock is fractured, or di- 

 vided, into parts so minute, by the intersection 

 of veins of quartz, or of carbonat of lime, or of 

 basalt, as to emulate the aggregate structure. 



i 



The two following modifications hold a sort 



of intermediate place between the accidents 

 arranged under Structure and those included 

 under the term Texture; and they may with 

 equal propriety, therefore, be considered in this 

 division. 



GRANULAR. 



The finer varieties of the aggregate structure 



