MONTHLY NOTICE. 



355 



MONTHLY NOTICE, 



December 1st. 1842. 



We insert this month an extremely interesting communi- 

 cation from a foreign contemporary, relating to a subject of 

 dispute at the present time amongst " Glacialists and one, 

 which as M. Elie de Beaumont has expressed it, is likely to 

 add much weight to the diluvio-glacial theory. We would, 

 therefore, advise a careful study of the facts contained in it, 

 as they tend, in our opinion, so to modify the glacial 

 theory (so called) as to make it accordant with the more 

 plausible ideas recapitulated in our annual summary for this 

 past year, in opposition, in part, to the glacial theory, of 

 which the following are the principal constituents — viz. : 



1. — The movement of glaciers is not the result of their 

 weight, but is owing to an augmentation in the volume of 

 ice, resulting from infiltrated water, subsequently frozen. 



2. — Consequently, the movement and transport of large 

 masses is dependant upon the continual change of external 

 temperature between the degrees of heat, whether positive or 

 negative. 



3. — The rocks submitted to the pressures of the glacier 

 bear traces of the action of stones and sand, caused by the 

 glaciers, in progressive movements, forcing them against the 

 rocks, which are consequently grounded, and striated in a 

 peculiar manner. 



4. — Many circumstances of a comparatively recent epoch, 

 prove that the glaciers, both on the north and south of the 

 Alps, were much more extensive than at present. 



5. — No hypothesis explains so clearly the phenomena of 

 erratic blocks, as the presumption that they were transported 

 from their original sites, to those in which they are now 

 found, by the action of the glaciers. 



VOL. I. — NO. XII. 2 C 



