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VEINED. 



This peculiar disposition seems properly 

 to appertain to the circumstance of internal 

 structure in rocks. It comprises, not merely 

 those appearances which are only to be dis- 

 covered by the action of the weather, but 

 many of those visible veins which do not pass 

 out of one rock into another, and which consist 

 of the same substances as the including mass, 

 under some variety of aggregation. It thus 

 includes some of the contemporaneous veins 

 of geologists ; a term 'applied in so many ways 

 as to be a source of considerable inconvenience. 



In some examples of this structure, a single 

 vein is sometimes found traversing a mass ; or 

 there are two, or more, either separated, or 

 interfering in some way. It is not unfrequent, 

 in this case, to find the same peculiarity of aspect 

 which distinguishes the vein, disposed, in some 

 other place, in irregular patches, and, conse- 

 quently, in a kind of concretionary form. This 

 occurrence is common in granite. 



The sizes of such veins vary from the 

 breadth of a foot or more, to one of less than 



