ANNIVERSARY ADDRESS OF THE PRESIDENT. IxXXvil 



may be time to enter into a critical examination of the vaguer evi- 

 dence on which its extension to other quarters of the globe must 

 necessarily rest. I may here, however, mention one conclusion of 

 our author, which, to those not previously acquainted with it, will 

 probably appear somewhat startling. The very recent date assigned 

 by him, not merely to minor moyements in the Alps, but to those 

 which were principally instrumental in giving its actual form and 

 altitude to that magnificent chain, will probably have surprised 

 many geologists ; but it is a far bolder step to assert, with M. de 

 Beaumont, that the whole range of the Andes may probably have 

 been elevated since man became an inhabitant of our globe, and that 

 the deluge may have been the consequence of its upheaval. Such 

 conclusions can only rest on the immense relative importance assigned 

 to the latest movements to which these great mountain ranges have 

 been subjected in comparison 'with the earlier movements which 

 may have affected them, and to which, for aught that is shown to 

 the contrary, they may really owe by far the greater part of their 

 elevation. But this latter view would be altogether inconsistent 

 with the general principle of instantaneous elevation which forms 

 the basis of M. de Beaumont's theory. 



The great defect in the evidence adduced by M. de Beaumont in 

 support of his theory is in the want of independent proof of the 

 synchronism of lines of elevation referred to the same system. A 

 general synchronism in the periods of great disturbance throughout 

 such a region as "Western Europe, or even throughout regions of 

 greater geographical extent, is not difficult to establish on the best 

 evidence which geological phsenomena can afford us ; but when we 

 attempt to determine the exact relative dates of the particular move- 

 ments of each period, we find ourselves beset with numerous diffi- 

 culties. I have brought before you a sufficient number of facts respect- 

 ing the palaeozoic periods to exemplify these difficulties in our own 

 country, and if they exist here, what must be the amount of uncer- 

 tainty in other regions in which the geological structure is compara- 

 tively so imperfectly known ! Again, these relative epochs during the 

 Tertiary period must necessarily be of extremely difficult determination, 

 on account of the small areas over which each separate formation of 

 that period preserves any character of continuity, and the consequent 

 difficulty of establishing in one district the exact equivalent of any 

 proposed formation in another. I need scarcely remind you of the 

 exemplification of what I am now stating afforded by the tertiary 

 basins of the North of France, Belgium, and the South-East of En- 

 gland, situated as these basins are in close contiguity with each other, 

 and subjected as they have been to long-continued and searching 

 investigation. Such considerations render it almost certain that 

 M. de Beaumont's theory, as now expounded by him, must receive 

 many modifications, and it still remains to be seen how far the 

 changes which extended inquiry may demand, can be made consist- 

 ently with the fundamental principles of the theory. The author 

 has already been obliged to make modifications in consequence of 

 our advancing knowledge. The date of the elevation of the 



