8 TALKS ABOUT THE SOIL. 



This idea of the rocks being skeletons of the hills, we 

 thus see, is a purely fanciful notion. 



A mere fancy may suggest a truth. The hills and 

 mountains are gigantic masses of rock. What of the 

 meadows, the sandy wastes along the shore, the wide 

 prairies where not a stone as big as a walnut can be 

 found ? Is there no rocky frame to these level parts 

 of the world ? Certainly. The whole exterior surface 

 of the earth is rock. Under the prairie, under the 

 seas, under the wide pine-barrens of the South, lie the 

 deep rocks, the foundations that hold up all we can 

 see of the world. A vast shell of rock really makes 

 the skeleton of the earth. 'What is under the stony 

 frame, we do not know ; perhaps more rock to the very 

 centre of the planet. Perhaps the rock is glowing 

 white with heat. In the coal-mine we found it very 

 warm. Volcanoes and hot springs plainly show there 

 is heat and fire somewhere below the ground. Where, 

 no one can tell. Perhaps no man will ever know. It 

 does not matter. The rocky shell that completely 

 covers all from sight, securely holds us up ; and upon 

 its surface we live and work. At times there are 

 movements and earthquakes ; yet the planet, as a whole, 

 keeps quiet and secure. The rocks make the great 

 bone-like frame of the earth, and it is these rocks we 

 are first to study. Over a living skeleton is always 

 flesh and skin, clothing it all from sight. So it is with 

 the earth. The rocky frame of the globe is covered 

 with an outside skin of the greatest beauty. This skin 

 or outside part is called the soil. It covers nearly all 



