THE 



EDINBURGH NEW 

 PHILOSOPHICAL JOURNAL. 



On the most recent Disturbance of the Crust of the Earth, in 

 respect to its suggesting an Hypothesis to account Jor the 

 Origin of Glaciers. By Sir G. S. Mackenzie, Bart., 

 F.R.S.L. & Ed., he. Read before the Royal Society of 

 Edinburgh on the 7th March 1842. Communicated by the 

 Author. 



The attention of geologists has for some time been directed 

 to the present condition of the surface of the earth, in a man- 

 ner calculated to bring many new facts to light, by means of 

 a more careful examination of those already observed, and 

 which have given rise to various speculations respecting their 

 origin. There may be perhaps too great a tendency towards 

 attributing to a single cause the whole phenomena of a class. 

 While the debacle theory appears adequate to explain a great 

 ileal in reference to transported materials, there exist obsta- 

 cles to its general application not yet cleared away ; but, in 

 regard to various local appearances, it is likely, when modi- 

 fied, to stand its ground in special cases. The same remai'k 

 may be applied to the glacier theory. Professor Agassiz gave 

 aip his idea of a universal glacier having existed, and having 

 been elevated at the same time with the Alps, probably be- 

 <}ause he could find no origin from whence such a coating of 

 ice could have been derived. Some have appealed to astro- 

 nomy for proof of the possibility of the surface of the earth 

 having been at one period frozen ; supposing that certain 



VOL. XXXHL NO. LXV.— JULY 1842. A 



