24 TALKS ABOUT THE SOIL. 



that the tendency of the rocks is to crumble and fall 

 down under the influence of weathering, and that this 

 weathering has undoubtedly been going on without 

 interruption since the first rocks appeared. We will 

 all, whether living near the hills or on the most level 

 prairie, now join in still further observations out of 

 doors, in the neighborhood of our homes. 



If the mountains crumble and fall into loose heaps 

 of broken stone, why do we not find the heaps just 

 where they fall ? Why is there a long, sloping talus 

 at every denuded cliff? We might expect, from all 

 we have learned, that there would be masses of loose 

 stones about every ruined mountain, and that the 

 broad plains, like the great valley between the Alle- 

 ghanies and the Rocky Mountains, would be bare rock, 

 just as at the beginning. We know that this is not so, 

 and that our prairie States, far from any mountains, 

 often have deep soils, rich in the remains of long- 

 vanished hills. We must find the answer to these 

 questions by observing what is going on about us 

 every day. 



Go to the nearest brook or river after a heavy rain. 

 Observe the color of the water. It is perhaps yellow 

 or brown, with mud and floating sediment. If you 

 cannot do this, observe the little streams of water in 

 the road or in the street-gutter at the beginning of a 

 smart shower. The water is muddy and discolored. 

 It is evident the water is carrying along many fine 

 particles of earth and soil. If the stream is in a hilly 

 country, we may observe, that, beside the fine mud 



