GUERNSEY CLAYS, 



BY MR. G. DERRICK. 



Guernsey offers a better field for the mineralogist than for 

 the geologist. Where fossils abound they speedily attract the 

 attention of observant individuals, many young persons 

 become interested in the search for them, and so gradually 

 acquire a taste for geology, which in such districts become a 

 favourite science. Guernsey unfortunately possesses no fos- 

 siliferous rocks, and so geology obtains few enthusiastic 

 followers ; but those who have devoted themselves to this 

 science have gradually obtained a fairly complete acquaint- 

 ance with the characteristics of our rocks, and in the article 

 written by the Rev. E. Hill on this subject (see Transactions 

 of Geological Society), we appear to have a reliable account of 

 the variety and disposition of the different rock formations. 

 But in my estimation too little attention has been given to 

 the superficial deposits found in the island. I hope the 

 discussion this evening will draw attention to this subject 

 and lead to the collection of information, which, when laid 

 before some specialists will enable them to give an authorita- 

 tive idea of the origin and relative ages of these deposits, and 

 perhaps even to show their connection with the tertiary 

 deposits of England and France. 



I do not wish on this occasion to open the question of all 

 the superficial deposits, for that would afford matter for many 

 evenings ; it would include (1) raised and ancient beaches ; 

 (2) peat and the submerged forest ; (3) the sand deposits of 

 the north-western coast : (4) the landslips from the cliffs on 

 the south and east coasts ; (5) the clays and loams, and (6) 

 the varied soil of the island. 



One of the duties devolving upon this Society is to make 

 a list of the various ancient beaches with accurate details of 

 their elevation and composition. The peat has received very 

 little attention, accurate measurement and close examination 

 might lead to the correlation of the different deposits and 



five an idea of the relative periods of their formation. The 

 eposits are very extensive ; peat has been met with not only 



