80 J. A. Birds — Geology of the Channel Islands. 



lat. 37° to 72°, or upwards of 2000 miles ; but there is a charm in 

 such wide horizons, and it is a very allowable indulgence so to 

 connect the little with the great, and to consider the position of such 

 little specks in relation to the geography of Europe ; one might 

 almost as well say, of the world at large. Having refreshed our- 

 selves, however, with such a glance at their widest geographical 

 relations, we must be content to confine our view within a very 

 much narrower compass, and to consider these islands simply as 

 relics of a tract, which once formed part of what is now Normandy 

 and Brittany ; just as the Scilly Isles and Lundy Isle are relics of 

 an area which once was connected with Cornwall and Devonshire — 

 the original and actual basis indeed of Arthur's legendary kingdom 

 of Lyonnesse. This itself is no narrow view ; but even if it were, 

 still we are not under any necessity — as in geology one never is — of 

 losing a great horizon and burying ourselves in a mass of details ; 

 the only difference is that we must change our point of view, and 

 regard the area under considei'ation in the aspect, not of space, but 

 of time. Viewed in this way the series of rocks become so many 

 visible and tangible links, or landmarks rather — the chain being so 

 broken — leading the mind back into an almost infinite past. 



It is not my purpose, of course, in this paper, to attempt any- 

 thing like a complete account, or even a resume, of the geology 

 of these isles; that may be fully gathered from such articles as Dr. 

 MacCulloch's, and others in the Transactions, Proceedings, and 

 Quarterly Journal of the Geological Society ; from Duncan's " His- 

 tory of Guernsey " ; and, above all,' from Prof. Ansted and Dr. 

 Latham's work on the '•' Channel Islands." All that I desire to do 

 is, to ask one or two questions about points which seem to me of 

 chief interest and importance, to bring together information from 

 the above works and elsewhere upon these points, and to add to 

 this the result of my own observation during the latter part of last 

 year. 



The first question is as to the age of the granites, or rather 

 syenites, ' granitals,' schists, porphyries, sandstones, etc., of which 

 the islands consist. 



Besides Prof. Ansted's conjectures that the grits and sandstones 

 of Alderney are probably of Permian or Triassic age,^ and the older 

 conglomerate of Jersey of the age of the Cherbourg grits- (Bunter or 

 Lower Trias), I am not aware of any observations having been 

 published as to the date of the rocks. 



Looking at a geological map of the north of France, or of 

 Normandy and Brittany, with which the islands stand in closest 

 connexion, one would conjecture a priori that the sedimentary rocks 

 at least were either Silurian or Devonian, more especially when we 

 observe what is probably a continuation of these rocks across the 

 Channel in Devonshire and Cornwall.^ The only positive evidence 

 in favour of such a supposition, that I have seen, is a small patch or 



1 The Channel Islands, p. 269. ^ ibid, p. 274. 



3 See an article by the late Mr. Salter on " The Pebble Bed at Buddleigh 

 Salterton," Geol. Mao. 1864, Vol. I. p. 5, etc. 



