and the other Channel Islands. 1 3 



of the Anfroques is probably of a similar structure, and this is some- 

 what pointed out by their granitiform outline. 



SERCQ. 



The little Island of Sercq lies six miles to the east of Guernsey, 

 and is rather more than three miles in length. Its extreme breadth 

 is not more than a mile and a half, and its average breadth not quite 

 a mile. In one part, it is not many yards wide, being nearly 

 divided into two portions, connected only by a high and narrow 

 ridge. A small island, I'lsle des Marchands, lies on the west side 

 of it, and sundry detached rocks surround it on other sides. Though 

 of such small dimensions, it is more interesting to a mineralogist 

 than the other islands, not only from the greater variety of its rocks, 

 but from the more perfect exposure of its formation that is 

 afforded by the abrupt cliffs which bound it on all parts. Unlike 

 Guernsey or Alderney, it is a table land, having no declivity to the 

 sea at any part, except a small descent at its northern extremity. 

 The cliffs by which it is bounded are from one hundred to two 

 hundred feet high. Except the Isle des Marchands which I men- 

 tioned, the western shore is so abrupt that large ships may range 

 it very near without hazard. The eastern shore is less clean, and 

 is beset with ridges of rocks running far out into the sea. The 

 bottom is rocky. The eastern side of the land is also pretty uni- 

 formly about one third lower than the western, or it has a tendency 

 to rise towards the west. In a general view the western side is of 

 a trap and schistose formation, and the eastern of a granitic. It is 

 intersected by veins of greater magnitude, and a more decided 

 character than Guernsey, Alderney, or Jersey. The surface of 

 the island though high, is every where intersected by deep vallies j 



