liv PROCEEDINGS OP THE GEOLOGICAL SOCIETY. 



body of literature, much, more must I, elevated somewliat unex- 

 pectedly to the proud position of your President, crave your kind 

 consideration in being allowed to select, as the subject of my address, 

 only a comparatively limited district in the broad domain of our 

 Science. 



We retain, happily, among us still, perhaps the most active of 

 our number, eminent men who joined our Society in what we may 

 term its second generation. In their younger days geological 

 science, although rapidly increasing in its dimensions, was not yet 

 too extensive to forbid its entire ambit from being surveyed and 

 explored by a single mind. But the amazing advance of the science 

 within the last fifty years has rendered it necessary more than ever 

 to recognize the limited power of the human intellect. Not only 

 does the descriptive portion of physical geology carry us into a 

 multiplicity of details culled from all parts of the earth, but the 

 subdivision into numerous branches, all of them increasing with the 

 growth of other conterminous sciences, has established the necessity, 

 coupled with advantage to our progress, for working geologists to 

 lay special stress on some particular portion of our subject. 



The crowd of works which annually issue from the press of all 

 civilized countries precludes the possibility of referring to the whole 

 of them, except as a mere list of little more than their titles, and 

 renders it incumbent on a President to seek out amongst them either 

 those which may appear to be the more important, or which treat of 

 those particular subjects with which he may happen to be most 

 familiar. 



In considering the nature and history of the rocks which form 

 the crust of the globe, it appears to me that since Mr. Horner, a few 

 years ago, gave a full summary of what had been recently done to 

 elucidate the origin of the crystalline and metamorphic rocks, a 

 number of works have appeared, some of them as contributions to 

 our own Journal, others as independent treatises, which should 

 excite more than a passing interest. Views of a very conflicting 

 character have been brought forward: the Huttonian and Wer- 

 nerian controversy seems almost to be revived in a modified form ; 

 and amid the results of observation and of experiment so many 

 important facts have been elicited that I am induced to think it 

 desirable to place before you, even if it be only as a reminder, 

 some of the principal conclusions at which recent authors have 

 arrived. 



On looking round at the facilities offered to study by the constant 

 multiplication and improvement of geological maps, I think it 

 behoves me first to say a few words on the advancement of those 

 surveys in which we are most nearly interested. 



During the past year considerable progress in the field has been 

 made by the Geological Survey of Great Britain. The mapping of 

 the London Basin is now approaching completion, excepting on the 

 north-east ; and the last of the maps of the "Wealden area, that of 

 East Kent, is on the verge of being published. Pive sheets of sec- 

 tions across the "Weald are also being engraved, which, being on a 



