Amiiversary of \S3S. Address of the President. 509 



any member in one country, or the identification of similar members 

 in two countries, are, for the most part, problems admitting of a defi- 

 nite and exact solution. In countries out of this district, on the 

 other hand, we have not only to explore but to classify. We have 

 to divine their geological alphabet ; — to decipher as well as to read. 

 We have not only to discover of what British rocks the observed 

 ones are the equivalents, but we have to ascertain whether there 

 be an equivalence ; and where this relation vanishes, we have to 

 discover what new resemblances and differences of members are most 

 worthy our notice. The great difference in the nature of the geologist's 

 task in these two cases seems to me to make it desirable to employ 

 the familiar division of Home and Foreign Geology in a wider sense 

 than has hitherto been common, including in the former all that re- 

 gion of Europe which has had its order of strata well identified with 

 our own ; this distinction then I shall employ. 



1. Home (North European) Geology. — If we attempt, in this part of 

 our subject, to follow an order of strata, we must begin with the 

 oldest stratified rocks, though they are undoubtedly the most ob- 

 scure ; for the same reason which compels the historian of states to 

 begin with the dim twilight of their savage or heroic times ; namely, 

 because at the other extremity of the series there is no boundary ; 

 since the events of past ages and their records form an unbroken 

 series, leading us to the unfinished occurrences and works of to-day. 

 Going then as far back as the historian of the earth can discern any 

 light, and, for reasons which may hereafter be spoken of, shaping our 

 course by the stratified rocks alone, we should first have to ask what 

 addition has been made during the past year to our acquaintance 

 with those formations which have generally been called transition. 

 And here, gentlemen, many of you well know, that if I had had to 

 address you at a period a little later, I might have hoped to be able 

 to point out, among the labours of our members, some which may be 

 considered as events of primary importance in this part of our know- 

 ledge ; — steps which may be described as a new foundation rather 

 than a mere extension of this portion of European geology ; — a sepa- 

 ration and arrangement of transition rocks, which is likely to become 

 the type and classical model of that part of the geological series, as 

 Smith's arrangement of the oolites became the type of that portion 

 of the strata. I speak of Professor Sedgwick's views on the Cambrian 

 rocks, which occupy the north-west of Wales, and Mr. Murchison's 

 on the Silurian formations which cover the remainder of the princi- 

 pality and the adjacent parts of England. Mr. Murchison's work, 

 which cannot but be one of first-rate value and interest, will, I trust, 

 be in our hands in a few weeks ; and I should grieve to think that 

 Professor Sedgwick will be not only so unjust to his own reputation, 

 but so regardless of the convenience and expectations of geologists, as 

 to withhold from the world much longer the views which his saga- 

 cious and philosophical mind has extracted from the accumulated 

 labour of so many toilsome years, on a subject abandoned to him 

 mainly from its diflficulty and complexity. 



Turning then to the researches which have been laid before us 



