1849.] AUSTEN ON THE VALLEY OF THE ENGLISH CHANNEL. 69 



eluding the final exeavations of the valleys and the translation of 

 enormous masses of broken materials into the adjacent low countries 

 of France. 



In conclusion, it is suggested, that the dispersion of the|far-travelle 

 Alpine blocks is a very ancient phsenomenon in reference to the 

 historic eera, and must have been coeval with the spread of the 

 northern or Scandinavian erratics, which it has been demonstrated 

 was accomplished chiefly by floating ice, at a time when large 

 portions of the Continent and of the British Isles were under the 

 sea. Viewing it therefore as a subaqueous phsenomenon. Sir 

 Roderick is of opinion that the transport of the Alpine blocks to 

 the Jura falls strictly within the dominion of the geologist who treats 

 of far bygone events, and cannot be exclusively reasoned upon by 

 the meteorologist, who invokes a long series of years of sunless and 

 moist summers to account for the production of gigantic glaciers 

 upon land under present terrestrial conditions. This last hypothesis 

 is, it is shown, at variance even with the physical phaenomena in 

 and around the Alps, whilst it is in entire antagonism to the much 

 grander and clearly established distribution of the erratics of the 

 North during the glacial period. The efi'ect in each case is com- 

 mensurate with the cause. The Scandinavian chain, from whence 

 the blocks of northern Europe radiated, is of many times larger area 

 than the iVlps, and hence its blocks have spread over a much greater 

 space. All the chief difliculties of the problem vanish when it is ad- 

 mitted, that enormous changes of the level of the land in relation to 

 the waters have taken place since the distribution of large erratics ; 

 the great northern glacial continent having subsided, and the bottom 

 of the sea further south having been elevated into dry land, whilst 

 the Alps and Jura, formerly at lower levels, have been considerably 

 and irregularly raised. 



June 13, 1849. 

 The following communication was read : — 



On the Valley of the English Channel. 

 By Robert A. C. Austen, Esq., F.R.S., F.G.S. 



The valley of the English Channel presents two points of geological 

 interest which may be considered as new — the one relating to the 

 nature of its bed, as a guide to the conditions of origin of our older 

 marine formations ; the other to its age as an area of depression. For 

 the former purpose the area may appear to be too Umited ; the extent 

 of surface, however, from the Straits of Dover to the outward line of 

 soundings, is more than equal to the whole of the South of England 

 from the Land's End to the Wash, an area which comprises the whole 

 series of Enghsh geological formations. Having had frequent oppor- 

 tunities of cruising about this Channel, I have been enabled, at one 

 time or another, to visit nearly every portion of its shores on either 

 side, and to examine its bed with the dredge and sounding-lead. 



