330 EEV. E. HILL OS THE ROCKS OE 



*. 



a rock intruded into schists, bnt the intruder cannot be clearly 

 identified with the overlier. So far as a boundary can be traced on 

 tb,e steeps above, this is sinuous and irregular. It is lost on the 

 grassy summit of the island, but reappears on the eastern side, and 

 the junction may be seen at low tide without much difficulty a little 

 south of the Eperqueries. At the corner of the bay is a natural arch, 

 and here on the side of the passage the line of meeting can be traced 

 in an excellent section. On close scrutiny crystalline rock seems 

 to have broken up and run into schist. But at this place also, as if 

 to baffle inquiry, a dyke and a fault come together, and I doubt if a 

 sceptic could be shown enough for his conviction. 



Conclusive evidence is, however, afforded by the south-east junc- 

 tion (fig. 5). This occurs in Little Sark, on the south face of the 

 " High Cliff " opposite the isolated rock called Baleine *. The schists 



Fig. 5. — Hough sketch of Granite overlying Hornblende-schists at 

 south-east junction on Little SarJc. Schists perfectly bedded, 

 dipping S. W. 



are highly bedded, dipping S.W. at 45°. The general surface of 

 contact, as usual, agrees with the direction of the bedding-planes ; 

 but dykes can be seen to proceed from the main mass of upper 

 rock and to ramify among the lower. 



In the outlying island of Brecqhou also the hornblendic beds 

 dip in a westerly direction below crystalline rock. On the south side 

 a vertical cliff makes a clean section of the contact ; the upper rock 

 seems to lie, though very nearly, still not quite on a bedding-plane 

 of the lower. In the cliff about 100 yards east is a large lenticular 

 inclusion of crystalline rock differing scarcely at all from the upper 

 rock, and probably, therefore, a dyke from it. On the north side of 

 the island it is possible to stand on rock shelves and examine the 



* A fair view may be obtained from a boat, The crags look inaccessible, 

 but I believe a way down has been cut. I reached the spot from the creux 

 called the Pot, at low-water spring-tides; this access would seldom be safe. 



