1838.J 



a?id Boad Zemindaries, 



405 



red felspar, and occasional scales of mica, obscurely stratified, and 

 wasting in low flat domes. 



In other districts, the character of the rock is highly crystalline. 

 Felspar, in greatly increased proportion, appears in large sized 

 prisms, and hornblende is occasionally present. The strata affect the 

 bedded form, and disintegrate in prismatic and cuboidal masses, pic- 

 turesquely piled. 



The gneiss, less frequently, receives, in comparatively limited 

 tracts, a new character from the addition of garnets in great quantity. 

 By these it is pervaded now as a close granular quartzose rock, the 

 garnet sparks running in the dim lines of stratification; now, as a finely 

 laminar, though never schistose mass, the strata endlessly bent and 

 contorted. In the rock under this form, every variety of structure, of 

 texture, and of constitution prevails by turns. Hornstone, felspar, 

 mica, hornblende, and dark garnets appear mingled in every pro- 

 portion, and individually developed in great beauty. 



The rock thus constituted generally decomposes by exfoliation in 

 low undulating surfaces. 



The gneiss finally assumes throughout extensive districts a strong- 

 ly marked porphyritic character, its dark gray surface being strik= 

 ingly variegated by prisms of felspar from two to six inches ia length 

 which become white on exposure. 



This rock is every where traversed by quartz-veins, both transversely 

 and in the direction of the larainee. 



It is in some tracts also largely penetrated by granitic veins, on.; 

 every scale; in other districts these are entirely wanting. 



There occur likewise throughout this deposit occasional dykes of 

 greenstone or of hornblende rock, whose course the nature of the 

 surface renders it extremely difficult to trace. The bearing of the 

 observed beds, was nearly N..N. E. 



The general direction of the gneiss strata is N. easterly. They, 

 are inclined at every possible angle. 



The sandstone which replaces the gneiss is generlly constituted of 

 quartz and felspar, v.ilh mica in small quantity interposed in the. 

 lines of stratification. 



In texture it is both close and granular, and open and crystalline, 

 and of every degree of induration. In colour it is generally light 

 gray or of a yellovvish or reddish white. 



Its strata appear of every dimension ; and in the low country con- 

 formable to tii^ gneiss. Their dip in these tracts is in some degree 



