30 LEAVES FROM THE JBooK OF NATURE. 



life which is throbbing in this vast globe. Meteoric 

 stones, also, come like aerial messengers from distant, 

 unknown spheres, and speak loudly of the life in spaces 

 unknown to human vision. For stones travel as well as 

 life-endowed organic bodies; they are, in fact, the very 

 oldest travellers on earth of whom we have any knowl- 

 edge. The mountains are not everlasting, and the sea 

 is not eternal. Thousands of years ago, rocks began to 

 shiver in the fierce cold of the polar regions ; even 

 Sweden and Norway, Greenland and Spitzbergen, became 

 intolerable, and they set out on their great journey to 

 the warmer South. But huge, unwieldy travellers as they 

 were, they soon tired and rested awhile in the wide, 

 sandy wastes which stretch through Northern Europe and 

 Asia. Some, the large ones, remained there, bleak, blasted 

 masses of rock, sterile and stern, like grim giants of dark, 

 old ages. Their lighter companions, smaller and swifter, 

 rolled merrily on towards the foot of mountains, and 

 there they also lie, scattered over the plains of Europe 

 and Siberia. Science calls them "erratic" stones, the 

 people know them as " foundlings," for there they are, 

 like lost children, belonging to another climate and a dif- 

 ferent race from those which surround them. When they 

 travelled, man knows not. It must have been in times 

 of yore, however, when the great Northern Ocean covered 

 yet, with its dark waves, mountain and forest in the very 

 heart of the continent. Other blocks travelled against 

 their will, packed up in snow and ice. Whole islands 

 of ice, we know, were torn off by terrible convulsions 

 from the .coasts of Scandinavia; the storm-tossed sea 



