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biotite scales, and biotite with iron-ore and apatite seem also 

 to be abundant in the dark, irregular masses and veins 

 with which the rock is interwoven, and which, in my 

 opinion, derive from basalt mass that has penetrated into 

 the granite. 



It appears to me almost as if the rock just described 

 passed over into the true breccia which is extensively met 

 with on the border between granite and the alnöitic basalt rock. 

 In it we find everywhere numerous angular fragments which 

 presumably derive from the latter, besides which there is a 

 more or less abundant mass of a lighter colour, which evidently 

 consists to a great extent of the granite minerals. In the only 

 one of these varities that I examined closely this mass retires; 

 that it is not a normal granite can be seen from this, among 

 other things, that it now and then contains large crystallized 

 biotite individuals of the same appearance as in the alnöite. On 

 the other hand, granite occurs as well as basalt in the form of 

 angular fragments. A small piece of this kind, which was 

 examined microscopically, was almost destitute of quartz and 

 very violently crushed. For the rest, one can see, under the 

 microscope, that the matrix consists of a really new formation 

 and is largely composed of a compact mass rich in carbonate, 

 in which lie a number of fragments of crystals and rocks, which 

 must mostly come from the granite, but to a great extent also 

 from the basalt or rocks closely allied to it. The larger frag- 

 ments of basic rock show no specially remarkable qualities and 

 are described along with the main type. 



This however does not yet exhaust the breccia rocks of the 

 district. The alnöitic rock itself in the little mass, whose 

 contact I have described here in the first place, forms a true 

 breccia, in that it contains exceedingly numerous pieces of 

 varying size and character, belonging to the most varied types 

 of rock: granite, gneiss, basic rocks, qnartzitic forms, and, 



