180 Scientific Intelligence — Geology. 



another layer of sand, on which silt, and moss, and soil, might 

 again accumulate. The old country rhyme tells us it was 



" First a wood, and then a sea, 

 Now a moss and aye will be." 



But geology goes a step further back, and points to the proofs 

 that it was a sea before it was a forest ; and modern improv- 

 ment threatens soon to prove its prophecy in the last line 

 also false, by turning the waste moss into fertile corn fields. 

 — {W. Nicol, in Scotsman.) 



SCIENTIFIC INTELLIGENCE. 



GEOLOGY. 



1. On Glaciers. — ^M. Grange has sent a memoir to the Academy 

 of Sciences, entitled, '•' Researches on the Meteorological and Oror 

 graphical Causes which have made the extent of Glaciers to vary in 

 historical and geological times ; being a comparative study of the 

 Erratic Deposits of the north of Europe and the southern parts of 

 South America." 



In this work the author has endeavoured to shew precisely the 

 degree of the influence of cHmates on the development and extent 

 of glaciers. He particularly points out the considerable difference 

 which subsists in this respect between the marine and continental 

 climates of temperate latitudes. He concludes, from his own obser- 

 vations and those of others, that every important change in the ex- 

 tent of continents, whether proceeding from immersion or elevation 

 of the land, must bring on a proportional modification in the extent 

 and thickness of the glaciers. 



In a previous memoir presented to the Academy, and published 

 in 1846, he had shewn that we may explain the erratic deposit of 

 the north of Europe, and the grooving of the rocks, by the immer- 

 sion of the plains in which this formation occurs, an immersion 

 which had been followed by the extension of the glaciers ; and that 

 the complex^ characters resulting from this great geological event 

 might be referred either to the existence of glaciers and floating ice, 

 or the currents formed by the waters in the deep bottom of this sea. 

 In the memoir now presented, which is a succinct view of a much 

 more considerable work soon to be published, he shews that the cha- 

 racters of the erratic deposit of the south of South America are iden- 

 tical with those of the north of Europe, and that, in America, it was 



