Mr Murchison on the Glacial Theory. fBB 



S« far south as the latitude of 40°. Each of these would be on a small 

 scale what the polar nucleus was on a great scale, a centre of disper- 

 sion." 



In the meraoir upon Russia by M. de Vemeuil and myself, one obser- 

 vation, however, occurs, which has not found its way into the abstracts, 

 and which, therefore, I may advert to, as explaininsf why the rough de- 

 tritus of mud, sand, clay, and boulders so very seldom contains marine 

 femains. Such heaps are made up of materials, which we consider to 

 have been imbedded in a true terrestrial glacier, and therefore, though 

 detached, and floated to a distance, they never could afford more than 

 terrestrial detritus ; and if to this be added the consideration of how the 

 stranding of such masses would destroy animals in the vicinity, as sug- 

 gested by Darwin, we may rationally conceive why so few shells have 

 been discovered in this coarse detritus, whilst wc readily perceive why 

 the stones impacted in it should be scored and striated, and often polished. 



Besides the great advancement of our knowledge of terrestrial magne- 

 tism, which at some future day may be connected with our labours, the 

 Antarctic expedition, under the distinguished navigator Captain James 

 RosSj has, as might have been expected, thrown considerable light upon 

 the glacial theory. A few years only have passed since the existence of 

 an enormous mass of ice-clad land in the antarctic region, was announced 

 by an American squadron of geographical research. This great icy tract, 

 which was described as exhibiting hills and valleys, and even rocks upon 

 its surface, has entirel}^ disappeared in the short intervening time ; for 

 Captain Ross has sailed completely through the parallels of latitude and 

 in the same longitude which it was said to occupy. As we cannot sup- 

 pose that the American navigators were deceived by atmospheric pheno- 

 mena, so must we believe that what they took for solid land, was one of 

 the enormous accumulations of ice called " packs," the great source of 

 those enormous ice islands which periodically encumber the Southern 

 Seas. 



Continuing his progress towards the South Pole in almost open sea. 

 Captain J. Ross discovered, as he proudly says, " for the honour of Eng- 

 land," the southernmost known land, which he named Victoria, and which 

 he coasted for more than 8 degrees of latitude. This land rises in lofty 

 mountain peaks, from 9000 to 12,000 feet in height, perfectly covered 

 with eternal snow, from which glaciers descend, and project many miles 

 into the ocean, terminating in perpendicular lofty cliffs. The rocks which 

 could be examined were of igneous origin, and near the extreme south 

 point of his exploration, or in S. lat. 77° 32', long. 167° E., a magnificent 

 volcano was seen in full action, emitting flame and smoke at an altitude 

 of 12,400 feet. Further progress to the southward was then impeded by 

 an enormous barrier of ice, orglaciers 150 feet high, which stretched from 

 W.N W. to E.S.E., and which the bold seaman traced in continuity for 

 ^0 miles, to long. E. 191° 23', and lat S. 78°. That tliis barrier was a 

 true glacier was inferred from the existence of a very lofty chain of moun- 



