244 SPARKS FROM A GEOLOGIST'S HAMMER. 



nature of the events which resulted in the burial of 

 entire mammoths in glacier-ice. That the climate in 

 which they had lived was not tropical, like that of Af- 

 rica or India, may be regarded as proved by the presence 

 of the fur in which these animals were clothed. That it 

 was not similar to the existing climate of northern Si- 

 beria is apparent from the consideration that such a 

 climate would not yield the requisite supply of vegeta- 

 tion to sustain their existence. More especially would 

 forest vegetation be wanting, which seems to have been 

 designed as the main reliance for proboscidians. North- 

 ern Siberia must, therefore, have possessed a temperate 

 climate. If the change to an arctic climate had been 

 gradual, the herds of mammoths would probably have 

 slowly migrated southward; or, if no actual migration oc- 

 curred, the extinction of the mammoth population would 

 have been distributed over many years, and the destruc- 

 tion of individuals would have taken place at tempera- 

 tures which were still insufficiently rigorous to preserve 

 their carcasses for a hundred ages. Whole herds of mam- 

 moths must have been overwhelmed by a sudden invasion 

 of arctic weather. Some secular change produced an un- 

 precedented precipitation of snow. We may imagine ele- 

 phantine communities huddled together in the sheltering 

 valleys and in the deep defiles of the rivers, where, on 

 previous occasions, they had found that protection which 

 carried them safely through wintry storms. But now, 

 the snow-fall found no pause. Like cattle overwhelmed 

 in the gorges of Montana, the mammoths were rapidly 

 buried. By precipitation and by drifting, fifty feet of 

 snow, perhaps, accumulated above them. They must 

 perish; and with the sudden change in the climate, their 



