240 Mb. HOPKINS, ON THE TRANSPORT OF ERRATIC BLOCKS. 



surface, there remains no difficulty in accounting for the transport of the prodigious block above 

 mentioned from the Alps to the Jura; a fact which on any other hypothesis hitherto made, 

 presents, in my opinion, mechanical difficulties totally insurmountable. The supposition of an 

 elevation of 1600 or 1700 feet since the period of transport offers, as I conceive, no a priori 

 difficulty, when we recollect the evidences of recent elevation in other places. With conclusive 

 evidence that Snowdon has been elevated 1200 or 1300 feet within a period which we have no 

 reason for supposing more remote than that of the transport of erratic blocks, there can be 

 little hesitation in admitting the elevation above supposed in the region of the Alps within the 

 same period, as an hypothesis as probable at least as any other which might be adopted. 



W. HOPKINS. 



Cahbridoe, 

 April 29, 1844. 



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