62 



tion is, that the ingredients of the basalt have a very great 

 difficulty in appearing in the form of sand, so that even a very 

 small conveyance of quartziferous material will be observable in 

 the sand. Hence arises the characteristic phenomenon, that in 

 the localities where the coarser ingredients would be expected 

 to be far richer in quartz than the finer ones, the opposite is 

 almost always the case. 



Only two different sizes of ingredients in the samples 

 have been examined, viz. the stones over A^^, and the sand 

 between 0*05, and 0*5°i™. The ingredients lying between 

 0*5, and i^^ are not very well adapted for examination, as they 

 are too small for the rock to be determined by them, and too 

 large for a direct microscopic examination. Nor have the in- 

 gredients under 0*05™"! been taken into consideration, partly 

 because they are rather small for an exact determination, and 

 partly also because they have a constitution which is closely 

 related to that of the sand, the only difference being that the 

 amount of quartz is even larger for the reasons that have been 

 stated above. 



The stony ingredients of the samples. 



(Over 4mm ) 



No. 1. 



Granite-Gneiss, 4. 



Sediments 4. Consisting of: quartzite 1 , finely grained 

 grey sandstone 1 , loose sandstone-slate with mica 1 , grey 

 slate 1. 



No. 2. 

 Basalt 2. 

 Granite-Gneiss 5. 



Sediments 2. Consisting of: quartzite 1 , sandstone-slate 

 with mica 1. 



I 



