142 M. Desor on 



or any other violent agent, they would have been broken, or 

 at least much worn. But, should we refuse to admit the 

 evidence which these shells offer, we cannot deny the proof 

 afforded by the serpulas of Christiania and the barnacles of 

 Uddevalla. whose shells still adhere to the rocks far above 

 the sea. 



On the other hand, the fact tliat the striae and furrows are 

 continued beneath the waters of the sea, attests no less strongly 

 that at a certain epoch the land must have been more ele- 

 vated than now. In fact, it is a point on which the partizans 

 of different hypotheses are nearly agreed, that the pheno- 

 mena of erratics took place over a submerged country. Gla- 

 ciers can advance only as far as the limits of the land. We 

 learn, from the observations of M. Martins, that even the 

 glaciers of Spitzbergen do not project beneath the sea ; for, 

 as the temperature of the water is above that of ice, it melts 

 the glaciers by its contact, and a considerable space, equal 

 to the height of the tide, separates the glacier from the wa- 

 ter.* 



But if, as I believe I have sufficiently proved, the polished 

 surfaces of the north have been occasioned by immense gla- 

 ciers, which have transported from afar the erratic blocks of 

 Scandinavia, and furnished the materials of the diluvium and 

 of the osars^ it follows, that the whole country which bears 

 traces of scratches, must have been out of water when the 

 glaciers produced this polishing, and produced the striae and 

 furrows which we now see there. If these striae were exactly 

 at the level of the sea, we might suppose that Scandinavia 

 was then at the same elevation as at the present day* But 

 we have seen numerous cases in that island, in which the 

 furrows are found under the sea ; from which facts we must 

 conclude, according to the principles laid down, that the land 

 at that epoch was as much above its present height as the 



* In order that glaciers should advance upon the bottom of the sea, it iS 

 necessary that the temperature of the water should bo below zero the year 

 through ; but such a climate would render the formation of glaciers impossible. 

 A humid atmosphere, rather than a severe temperature, is necessary to the ex- 

 istence of glaciers, and the former is incompatible with the temperature of a 

 sea constantly below zero. 



