164 Messrs. Von Oeynhausen and Von Declien on the 



quartz vein above mentioned, which also does not change the 

 appearance of the granite, where it is intersected by it. The 

 granite vein (C) spHts into three branches ; one running to the 

 north is to be seen for some distance, another running to the 

 south stops at a very short distance. At this place several frag- 

 ments of killas lie in the main or middle branch of the granite 

 vein. Some small open strings intersect the granite vein ; and 

 in its turn it intersects several quartz veins. Further off" the 

 granite divides into two branches, which are both intersected 

 by a quartz vein ; one of these branches ends before it reaches 

 low-water mark, but the other is visible through a length of 

 nearly 150 feet, and then goes into the sea. It is not more 

 than five inches wide, and not less than two or three. 



II. Roscmodris. — About three miles to the south-west of 

 Mousehole is situated Carnsilver Cove, on the western side of 

 the promontory of Rosemodris, which consists of a detached 

 mass of killas, being merely hornblende-slate and greenstone. 

 In this cove just mentioned occurs the junction of both rocks. 

 The granite is rather fine-grained than large-grained, but it 

 shows several modifications in its texture. Veins of black 

 schorl, often two or three feet wide, intersect the granite in a 

 nearly perpendicular position, and appear like black ribbons 

 on the white wall of the granite. They are to be seen for the 

 length of four or five hundred feet. Two large veins of schorl 

 running parallel at the distance of about four feet for a con- 

 sidei'able length, unite themselves without intersecting each 

 other ; another vein of the same constituent parts intersects 

 both, under nearly a right angle, without heaving them. The 

 united veins run against the junction of the granite and killas ; 

 it is to be lamented that large blocks fallen dow^n from the cliffs 

 hide the spot, where they must join this line. At the per- 

 pendicular wall on the east side of the cove, consisting merely 

 of killas, there is not to be seen any trace of a schorl vein ; and 

 whether any one of the granite veins which occur here very 

 frequently is the prolongation of this schorl vein or not, must 

 remain doubtful. The schorl veins consist of a body of white 

 quartz, in which the crystals of schorl occur so plentifully that 

 at some distance it appears only black. On both walls is a 

 string of quartz which contains less schorl than the middle part; 

 these strings are separated from the granite by a vei'y small 

 interstice, which presents a colour and appearance somewhat 

 different from the general appearance of the main body. 



Fig. 2. presents a plan of Carnsilver Cove. Fig. 3. a view of the 

 eastern wall of the cove, consisting of killas. The strata of the 

 killas run east and west dipping to the south, forming an angle of 

 30 degrees with the horizon. The bottom of the cove is granite, 



of 



