MONTHLY NOTICE. 



£5 



MONTHLY NOTICE. 



1st. March, 1842. 



The perseverance which has been displayed by both Bri- 

 tish and Foreign Geologists in tracing the evidences of 

 glacial action^ affords a very striking proof of the high opi- 

 nion in which the theory is held, not however, be it under- 

 stoodj as regards the problematic views which offer the 

 widest scope, but in respect of glacial action having been one 

 of the most prominent agents in certain transformations of 

 the rocks composing the earth^s crust. Since our periodi- 

 cal summary in January last we have become acquainted with 

 observations made in various parts of this country and 

 abroad^ adding valuable testimonies to those already ad- 

 vanced in support of this interesting theory. The report by 

 Dr. Buckland on evidences of this agency in Snowdonia, and 

 confirmatory observations made in the same quarter by the 

 late Mr. Bowman, so shortly before his death, are perhaps 

 the strongest evidences of any heretofore adduced, as to the 

 real effect, or to speak more correctly, the common effect of 

 glacial action. When we advance this opinion, we would 

 premise for the benefit of those less informed on this subject, 

 that it is in contradistinction to the theory of general centres 

 of glacial action, which met with very doubtful approval at 

 the meetings of the Geological Institutions of this country; 

 it was there argued, with reference to the position of these 

 centres, and the intervention of certain elevations between 

 their position and that of the present localities of erratic 

 blocks, that the elevation of the centres referred to must 

 have been so great, in order to afford the inclination required 

 for the descent of the glaciers and the accompanying blocks 

 of stone, that without better substantiated evidence it would 

 be next akin to folly to assume their existence, when the 



VOL. I. — NO. Ill, F 



