A Period in the History of our Planet. 17 



the deep azure of the cheerful sky, and high stretches their sum- 

 niit, whilst their base is encircled with the impenetrable mist- 

 wall which hides the doings of man below. So peculiar is the 

 impression of this picture, bringing us so completely in contact 

 with nature in her simple grandeur ; so strangely is the suscepti- 

 ble mind struck with this vision, where nothing betrays the life 

 which everywhere else plants its traces on our environs, that 

 whoever enjoys this sight for the first time must preserve it 

 amongst his most pleasant recollections. Such, I conceive, if 

 I may be allowed to compare so small a tract with what was 

 boundless, such may have been the appearance of our qarth, 

 when, at the glacial period, a rigid snow-crust covered its 

 surface. 



The earth had already assumed its present contour, with the 

 exception, perhaps, of the principal range of the Alpine chain, 

 and of the mountains that rose simultaneously with it : Mont 

 Blanc had already raised its head above the surrounding plains ; 

 the broad ridge of the Jura, the Vosges, the Black Forest, 

 the mountains of England and of Sweden, had been the wit- 

 nesses of its elevation. Then numbness seized the light 

 " sailors of the atmosphere," the clouds and vapours ; icy 

 winds drove them in a solid form to the earth, and, like a huge 

 winding-sheet, they enveloped the polar regions, the north of 

 Europe and of Asia. The British islands, Sweden, Norway 

 and liussia, Germany and France, the mountainous regions of 

 the Tyrol and of Switzerland, down to the happy fields of 

 Italy, together with the continent of northern Asia, formed 

 undoubtedly but one icefield, whose southern limits investiga- 

 tion has not yet determined. And as on the eastern hemi- 

 sphere, so also orithe western, over the wide continent of North 

 America, there extended a similar plain of ice, the boundaries 

 of which are in like manner still unascertained. The polar 

 ice which at the present day covers the miserable regions of 

 Spitzbergen, Greenland, and Siberia, extended far into the 

 temperate zones of both hemispheres, leaving probably but a 

 broader or narrower belt around the equator, upon which 

 there were constantly developed aqueous vapours, which again 

 condensed at the poles ; nay, if Tschudi's observations in the 



VOL. XXXV. NO. LXIX. JULY 1843. B 



