112 



THE GEOLOGIST. 



thickness, and would more deserve the name of plastic clay. I have reason to 

 believe, moreover, that this deposit is not always present ; as I have observed, 

 only a slight trace of it in a section that is exposed, of the Thanet sands at 

 Wingham, where the section exhibited reaches to the chalk. — George Dowker, 

 Stourmouth House, Wingham, Kent. 



Adhemar's Theory. — In- 'The Geologist" for January, there appears in the 

 " Notes and Queries," " An ' Early English' View of Adhemar's Theory." 

 Allow me to call your attention to a work, of which I copy below the title page. 



" An Essay on the Physico-Astronomical causes of Changes on the Earth's 

 Surface," by Sir Richard Phillips. With preface by Wilkn. Devonshire Saull, 

 E.G.S., &c.' Published by Sherwood, Gilbert, and Piper, 1832. A note shows 

 it was "First published in the Monthly Magaziue, in 1812, and re-printed with 

 other essays in 1821." The first publication, in 1812, was evidently the Maga- 

 zine "article" from which your correspondent quotes. — C. K. 



Bones of the Dodo. — At a meeting of the Zoological Society, Dec. 11th, Mr. 

 A. Newton noticed the discovery of some bones of the dodo in the Mauritius. 



Geological Excursions to the Channel Islands. — As comparatively 

 little is known of the geology of these extremely interesting islands, a few words 

 on the subject, perhaps, may not be unacceptable to the readers of " The 

 Geologist." The tourist, embarking either at Southampton or Weymouth, 

 will, on arriving at any one of the Channel Isles, be struck at once with the 

 difference in the geological character of the rocks around him to that of those 

 he has but the day before left behind him ; and on closer examination he will 

 perceive, instead of the low Tertiary cliffs of the Isle of Wight and its vicinity, 

 or the oolitic crags of Portland, that he is surrounded by mica-schist, granite, 

 and syenite, or other primary non-fossiliferous rocks. No true organic remains 

 there 'are within his reach, and during his stay in these islands he must content 

 himself with specimens of rocks and minerals. It is my intention therefore to 

 bring before my readers, in a few geological excursions, the principal features 

 of interest in these islands, hitherto almost unexplored by the geologist. 



To begin with Jersey — the largest and most important of the group. After 

 passing by the low sandy shore — where, by the bye an important and 

 comparatively recent geological change has taken place, which will be here- 

 after spoken of — and the tall granitic cliffs on the south-western side, which 

 have been here and there excavated into caverns by the action of the sea, the 

 traveller will arrive at the chief town, namely, St. Helier's, and on landing will 

 see on his right hand a fortress, which is built on a lofty rock of syenite. The 

 pier on which he will land is made of a beautiful pink or reddish-coloured 

 granite, which is extensively quarried on the opposite side of the island, at a 

 place called Mont Mado, where great crystals are occasionally found in the 

 granite quarries; but these are of rare occurrence. The granite here worked 

 varies in colour in the different quarries ; some is of the reddish variety above- 

 menl ioned, some is grey, and some of a yellowish tint.* The first place worthy of 

 notice to which I would introduce my readers is the north-western point of "the 

 low flat sandy bay before mentioned, where it was stated an important geological 

 change appears to have taken place. Tradition asserts that in this bay of 

 St. Oucn's there formerly was a large forest extending far out where the sea 

 now is, and w bich ages ago was buried beneath its waves. But let us inquire 

 into I his statement : in the the first place, there are landowners who even to this 

 day pay rent for laud which their ancestors formerly possessed in this forest. 

 At low water, during spring tides, if search be made, stumps of oak trees can 

 be found firmly imbedded in the sand ; these show, at any rate, that although 



* Due, T believe, to oxide of iron. There is only one narrow vein of this kind found in this 

 island. 



