A Story Outline of Evolution 



perhaps, billions of years, the crust became thicker and 

 thicker. While the crust was still glowing with heat it con- 

 tained all the elements that form the substance of all things 

 found in and on the earth today. In this cooling process, the 

 atoms of these gases began to unite. Two of these gases — 

 oxygen and hydrogen — by uniting two atoms of hydrogen 

 to one atom of oxygen forms water. When the first water 

 was formed, the earth's crust was still so hot that it formed 

 great clouds of steam mingled with air and as this steam was 

 condensed into raindrops that fell to the earth, it was sent 

 back in clouds of hissing steam. This process of change was 

 continued for many millions of years. As the cooling process 

 continued, great volcanoes would belch forth fire and liquid 

 rock from the seething interior of the earth. Again, the 

 earth's surface or crust would be broken and upheaved thus 

 forming the mountain ranges. After many millions of years, 

 the earth's crust became sufficiently cool to retain the falling 

 rain and the water began flowing over the surface of the 

 earth and to form the oceans, lakes and rivers. The rains 

 were constantly beating down the upthrust mountains and 

 the rivers were carrying away and leveling up this eroded 

 material. The rivers were forming the valleys and erosion 

 was now taking place. As the waves of the ocean were beat- 

 ing down the shores in some places, they were building up 

 and leveling them in others. 



Some of the igneous rocks that were formed from the 

 cooling gases of the flaming earth were ground into fine 

 particles and some dissolved into liquid crystals by the action 

 of moving water. These were again solidified Into different 



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