22 



NOTE. 



are fragments of the sienitic rock ; some of them from one to two feet in diameter, which 

 contain portions of the hornblende vein, so perfect and entire as to indicate the precise spot 

 from which they must have come; and it is particularly remarkable, that all these fragments 

 appear to have been carried upwards, considerably above the leval of the hornblende vein 

 which, with its containing rock, is obviously of anterior origin to the trap vein — a fact 

 that is also indicated by the superior induration and partially scorched appearance of the 

 sienite along its line of contact with the basalt. 



The following sketch represents the appearances here described 



A—The main rock of the bed and bank of the river, sienitic granite. 

 B — -The basaltic vein. 

 C — The hornblende vein. 

 D — The bed of the river. 



a. h. c. d. — Fragments of the main rock, containing portions of the hornblende vein 

 evidently forced upwards. 



e, e.— Other fragments of the main rock, without the hornblende vein. 



