THE STORY OF A STRANGE LAND. 2$$ 



other times the water came down little by little, 

 insinuating itself into many places at once. Then 

 the hot rocks threw it back in many little honey- 

 comb channels, and by the spreading of these 

 channels the rocks were at last crumbled to pieces. 

 The hard black lava or the glass-like obsidian were 

 changed to white kaolin as soft and powdery as 

 chalk. And as the water fought its way, gaining 

 a little every year, steadily working between the 

 joints in the enemy's armor and as surely being 

 thrown back with violence if it penetrated too far, 

 the animals and the plants followed in the wake of 

 the water, and took possession of the territory as 

 fast as it was won. 



At last the Pliocene times were over, for all 

 times come to an end. The one sure thins on the 



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earth is the certainty of change. With the change 

 of time came on the earth's great winter. The 

 snow-drifts on the lava were piled up mountain- 

 high. Snow is but ice in little fragments which 

 will grow solid under pressure. As the snow 

 accumulated it began to move, forming great 

 rivers of ice which ran down the courses of the 

 streams. And as these slowly moving, gigantic 

 ice-rivers tore away huge blocks of lava and pushed 

 them down the mountain-sides, where the rocks 

 had been softened by the action of steam, the ice 

 wore out deep valleys, and everything that it 

 touched was smoothed and polished. The winter 

 of the great Ice age lasted a very long time, many 

 thousands of years ; but, long as it was and long 

 ago, it came at last to an end, not to a full stop, 

 of course, for even now some of its snow still 



