STRATIGRAPHICAL ELEMENTS: CRYSTALLINES, ETC. 



67 



gneissose-granite are studied and traced out laterally as well as 

 forward and backward that we find them to be by no means con- 

 tinuous. They are then seen to die out and reappear again, to thin 

 away and thicken, and sometimes, but very rarely, to cut at a very 

 acute angle across the foliation planes of the schist. Near Man- 

 sehruh, as recorded by Mr. Wynne and as seen- by myself, we have 

 very conclusive evidence for the intrusive nature of the rock from 

 its mode of occurrence in the field. 



In the sketch section below I give an example of the invasion of 

 the quartzite by very distinct veins of gneissose-granite. The in- 

 truded rock, moreover, though without doubt belonging to the same 

 magma as the great mass of the gneissose-granite, differs slightly by 

 being of finer grain and with a larger amount of felspar and less of 

 the ferro-magnesian minerals, especially of the dark mica. This 

 difference, however, is exactly what would be expected to occur in a 

 narrow vein which has been forced in across the bedding of the 

 schists. 





Fig. 1. 

 About I miles N.E. from the D. B. Mansehruh along theGurhee-Hubeebooluh road. 

 Note.— The shaded portions are quartzite and the dotted granite. 

 F2 ( 67 ) 



