Anniversary o/* 1 8 3 8 . Address of the President. 5 1 3 



Before quitting our stratified rocks, I may notice thie commu- 

 nications respecting some of their fossils which we have received, 

 particularly that of Mr. Williamson on the fossil fishes of the Lan- 

 cashire coal field, and the establishment of the new genus Tropaeum, 

 separated from the Hamites of the green sand by Mr. Sowerby. 



In attempting to pursue a stratigraphical order, we are compelled 

 to reserve for a separate head the notice of unstratified rocks, since 

 their age and history are only known by the mode in which they in- 

 terrupt and disturb the rest of the series. We have not had many 

 communications respecting European rocks of this character ; but we 

 cannot but be struck by the subversion of ancient ideas which result 

 from the investigations of Messrs. Murchison and Sedgwick. They 

 have shown that the granite of Dartmoor, and consequently that of 

 Cornwall, formerly considered as one of the earliest monuments of 

 the primeval ages of the earth's history, is posterior to the deposit of 

 the culm measures. 



Advancing to newer phsenomena, we find the evidences of change 

 still unexhausted. We cannot but reflect how familiar those views 

 of the elevation and depression of portions of the earth's surface are 

 become, which were at first considered so strange and startling. This 

 is remarkably shown by the number of communications concerning 

 raised beaches which we have recently received. When we visit places 

 where these occur, and look at the winding shore, where the sea line 

 is faithfully followed or distantly imitated by terraces, sands and peb- 

 bles a little above it, we wonder that v:e should so long have been 

 blind to this kind of evidence. Such raised beaches have been de- 

 scribed during the past year, by Mr. Prestwich, as occurring in the 

 Murray Frith ; by Mr. Austen, in the valley of the Axe, the Exe, 

 and the Otter. Dr. Forchammer has given us the evidence of recent 

 elevation in the island of Bornholm ; Mr. Trevelyan has given us 

 similar evidence for the coast of Jutland, and the islands of Guernsey 

 and Jersey *. 



Mr. Morris's paper, describing a series of dislocations in the chalk 

 cliffs to the south of Ramsgate, marked by shifts in a bed of tabular 

 flint, may perhaps be considered as also affording evidence of violent 

 elevation. But since a small derangement of the conditions of sup- 

 port of any stratum might occasion dislocations of the scale of those 

 here described, it would probably be hazardous to consider them as 

 otherwise than local accidents. 



Among descriptions of the most recent geological phsenomena, I 

 must notice Mr. Clarke's paper on certain peat marshes and sub- 

 marine forests, which occur near Poole in Dorsetshire ; and in his 

 investigation of the causes which have produced the results now 

 visible, we may see by how easy a gradation descriptive geology 

 passes into the other portion of the subject, the study of the processes 

 by which change is produced. 



Finally, in concluding this survey of our descriptive home geology, 

 I notice, with great pleasure, Mr. Burr's communication of his notes 

 on the geology of the line of the proposed Birmingham and Glou- 

 [• See our present vohime, p. 284.] 



Phit, Mag. S. 3. Vol. 12. No. 77. June 1838. 2 U 



