ANNIVERSARY ADDRESS OF THE PRESIDENT. XXXIU 



rocks were made, if I mistake not, under impressions very unfavour- 

 able to those theories. Let me not be thought by this remark to 

 cast a reflection on American geologists, — men to whom our science 

 owes so much, and from whom it expects so much more in the noble 

 field in which they are labouring ; but we shall all do well. Gentle- 

 men, in learning to doubt the completeness of our observations on 

 difficult and controverted points when made under the strong im- 

 pressions of antecedent convictions. What I am especially anxious 

 for, is to see the American geologists resuming their observations in 

 all possible detail on this interesting subject, and with candid refer- 

 ence to the different physical causes to which smoothed and striated 

 rocks have been attributed. There are few pheenomena more likely 

 to elucidate the mixed and perplexing operations of the period to 

 which they must be referred. In northern Europe M. Sefstrom has 

 set us an admirable example by his careful and exact manner of 

 making his observations, and of mapping the results of them. There 

 is still much room for following out similar observations in the Scan- 

 dinavian regions. In our own islands, too, in Ireland, we have a field 

 in which much yet remains to be done. The observations on these 

 points by my friend Mr. Griffith were made, as he has told me, a 

 considerable time ago, and incidentally rather than as forming a 

 leading object in his researches. It is not therefore to be expected 

 that they should be sufficient to satisfy the present requirements of 

 the science. If by these remarks, Gentlemen, I should perchance lead 

 any geologist to reflect on the geological importance of this subject, 

 and to make and record his observations upon it with more than 

 ordinary accuracy, I feel that I shall be attaining one of the best 

 objects for the accomplishment of which an address of this kind may 

 be rendered useful, 



I shall now proceed to make a few observations on the arrange- 

 ment of the materials which constitute the Drift of northern Europe. 

 Though in many cases this arrangement seems very confused, as we 

 might expect it to be, there does appear to be frequently a decided 

 predominance of finer material in the lower, and of coarser ma- 

 terial in the upper portion. The lower mass frequently consists of 

 fine argillaceous and arenaceous sediment, sometimes mixed with 

 rolled pebbles, and reposing immediately on the polished and striated 

 rocks. Taking the whole area of deposition in Norway, Denmark, 

 Sweden, northern Russia, and northern Germany, the materials above 

 described constitute the great mass of the drift ; and on this mass 

 generally the large erratic blocks are superincumbent, though many 

 blocks are also found imbedded within its mass. The submarine 

 origin of the general mass is rendered unequivocal by the organic 

 remains which it is found in various localities to contain. 



The boundary of the area over which this enormous mass of de- 

 trital matter has been deposited proceeds from a point E. of the 

 White Sea towards the S.E. until it touches in one point only on the 

 Ural Mountains, whence it proceeds south of Moscow to the Carpa- 

 thian Mountains, and includes the whole of northern Germany. 

 Throughout Russia and Poland it is laid down in the map which ac- 



VOL, VIII. c 



