The Glacial Theory. 589 



observation, however, occurs which has not found its way into the 

 abstracts, and which, therefore, I may advert to, as explaining Avhy 

 the rough detritus of mud, sand, clay and boulders so very seldom 

 contains marine remains. 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 aiford 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 suggested by Darwin, we may rationally 

 conceive why so few shells have been discovered in this coarse de- 

 tritus, whilst we 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 

 magnetism, which at some future day may be connected with our la- 

 bours, the Antarctic expedition, under the distinguished navigator 

 Captain James Ross, has, as might have been expected, thrown con- 

 siderable light upon the glacial theory*. A few years only have 

 passed since the existence of an enornious 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 

 entirely 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 suppose that 

 the American navigators were deceived by atmospheric pheenomena, 

 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 numerous ice islands, which periodically encumber the South- 

 ern Seas. 



Continuing his progress towards the South Pole in almost open 

 sea, Captain J. Ross discovered, as he proudly says, " for the honour 

 of England," the southeinmost known land, which he named Vic- 

 toria, and which he coasted for more than eight 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 ex- 

 ploration, or in S. lat. 77° 32', long. 167° E., a magnificent volcano 

 was seen in full action, emitting tlame and smoke at an altitude of 

 12,'K)0 feet. Further progress to the southward was tiicn impeded 

 by an enormous barrier of ice, or glaciers 150 feet higii, which 

 stretciu^d from W.N.W. to E.S.E., and whicii the bold seaman traced 

 in continuity for .'500 miles, to long. E. 191° 23', and lat. S. 78°. 

 That tills barrier was a true glacier was inferred from the existence 

 of a very lofty chain of mountains behind it, the tops of which, as 

 seen from the mast-heads, were estimated to be a degree of latitude 

 to the south of the sea-face of this great wall of ice, at not more 



[* Capt. Ross's report of the discoveries made by the Antarctic Expedi- 

 tion will be found in Phil. Mag., Third scries, vol. xx. p. 141.] 



