FORBES — MINERALOGICAL RESEARCHES IN NORWAY. 



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Fig. 2. — Ground-plan of a granitic mass, with a quartz-nodule, in 

 gneiss at Flougstadoen. 



position as before, and the whole forms an irregular mass (in, n) in 

 the gneiss, and disturbs the foliation of this rock. 



Fig. 3 is a sketch drawn on an island near Ebo, where, as before, 

 a, a, is a lenticular quartz nodule, surrounded in this case by a mixture 

 of white oligoklase and chloritic mica, which also encloses the frag- 

 ments c, c, evidentlj'^ portions of the hornblendic gneiss which forms 



Fig. 3. — Ground-plan of a quartz-nodule in a granitic mass, with 

 fragments of the enclosing rock, from near Ebo. 



the surrounding rock ; several minerals are found here. 



On a much larger scale than any of these, fig, 4 represents the 

 section of the quartz quarry at Buoien ; here we have a large mass 

 of quartz, a, a, which is quarried for technical purposes, surrounded 



Fig. 4. — Section of a Quartz Quarry at Buoien, showing a lenticular 

 mass of quartz enveloped with granitic rock imbedded in gneiss. 



by a sheath of rock, which, within the lines b b, b b, is composed 

 of orthoklase, with a few large plates of black mica. At the point of 

 contact with the quartz, the orthoklase is often found in large and 

 sometimes defined crystals of several cubic feet contents. 



c 2 



