168 SPARKS FROM A GEOLOGIST'S HAMMER. 



enumerated have taken place during the present geolog- 

 ical period; and man, short-lived as his species has been, 

 has witnessed geological revolutions which have trans- 

 formed a continent, and rise in magnitude and impor- 

 tance to an equality with any which have visited the 

 surface of our earth in the whole progress of geological 

 cycles. 



It can hardly be doubted that man was present in 

 Europe while yet the continental glacier stretched into 

 central France and northern Italy. We must admit so 

 much, though denying his preglacial advent. We con- 

 template in our own time the Alpine glaciers as a fine 

 spectacle displayed in the midst of the populous homes of 

 European civilization. We do not shrink from their 

 presence, but most profoundly enjoy their novelty and 

 sublimity ; but could we adequately realize the historical 

 fact that these modern centers of frost and winter are 

 but the vestiges of the reign of a perpetual winter which 

 buried nearly the whole of Europe beneath a mantle of 

 snow and ice, which imposed the silence and solitude of 

 central Greenland for a term of unknown centuries, we 

 might contemplate these Alpine strongholds of frost and 

 desolation rather with the grim satisfaction which one 

 experiences at the fallen fortunes of an implacable enemy. 

 But our predecessors in Central Europe found themselves 

 on the borders of an ice-cap which to them seemed as 

 changeless and eternal as the glacier sheets of the Arctic 

 zone. Generation after generation came and disappeared, 

 and the glaciers almost imperceptibly retreated. European 

 man, accompanied by the reindeer and other northern 

 types of animals, followed the retreating glacier to the 

 shores of Lapland and the slopes of the Alps. In the 



