On the Phenomena of Erratic Blocks in Northern Europe. 141 



not cool more than l''-5 in consequence of its direct radia- 

 tion. 



I may finally add, that the part performed by stagnant air 

 in the phenomena of nocturnal refrigeration, appears to me 

 to have modified certain experimental data which have been 

 founded on for calculating the temperature of space. 



On the Relations rohich exist between the Phenomena of Er- 

 ratic Blocks in Northern Europe and the Elevations of Scaix- 

 dinavia. By M. Desor.* 



There is a point in the phenomena of boulders not hitherto 

 presented, which appears to me capable of throwing much 

 light on the question that now engages our attention : it is the 

 examination of the connection which subsists between the erra- 

 tic blocks of Northern Europe and the elevation of upraising 

 of Scandinavia. These relations are the more imnortant, as 

 they admirably explain some circumstances whicli are pecu- 

 liar to the erratics of the north, and of which there is no ex- 

 ample in Switzerland. These peculiarities are \st, the oc- 

 currence of polished and grooved surfaces beneath the pre- 

 sent level of the sea ; 2d, the existence of marine shells at- 

 tached to the polished rocks at a height much above the 

 present level of the sea ; So?, the presence of marine shells 

 in the midst of the diluvium, even at an elevation of 800 

 feet ; 4«^, the osars, or ridges of boulders and stones which 

 contain the shells of the Baltic. 



Among the phenomena which prove so fully the instability 

 of the Scandinavian soil, there are some facts which indicate 

 the rising of the land, while others, on the contrary, at- 

 test the subsidence. Thus we cannot have less equivocal 

 proof of an elevation of a country, than the occurrence, at a 

 great height, and at a considerable distance from the coast, 

 of shells now inhabiting the adjacent seas, and whose perfect 

 state of preservation leaves no doubt that they lived where 

 they now occur ; for, had they been transported by a current 



* Communicated, by the Author through Prof. Agassiz, to Editor of the Ame- 

 rican Journal of Science and Arts, May 1847. 



