A Little Astronomy and Geology 



the sun radiates, yet the earth Is receiving energy from the 

 sun at the rate of 160,000 horse-power for every man, 

 woman and child living on it. The sun is a star and to the 

 inhabitants of the earth, it is the most Important member of 

 our entire solar system because all life depends on it. 



There is no known means of estimating the age of the 

 earth prior to the time when stratified rocks began to form 

 since there Is no available data upon which a reasonable esti- 

 mate may be made. Geologic time, therefore. Is generally 

 understood to begin when the earth reached Its present form 

 and condition. The sedimentary rocks furnish a starting 

 point where estimates may be based on a study of the rate of 

 erosion, the thickness of the stratified rocks and many other 

 physical conditions so that the estimates now made are re- 

 moved from the realm of mere unintelligible guesses. Any 

 estimate now made as to the age of the earth since sedimen- 

 tation began to take place may be many millions of years in 

 error because it Is not known what different conditions may 

 have existed in the past. But the general conclusion among 

 geologists Is that many millions of years — some estimates 

 as low as 100 millions of years, and some as high as 1,000 

 million years — have elapsed since sedimentation began to 

 take place. Evolution is not concerned so much with the 

 time as it is with the method of creation. 



As this great blazing ma^ss of gas from which the earth 

 was formed took its position in the solar system and began 

 its endless journey In space under the control of Nature's 

 laws, it took the form of a sphere and It began to cool. Some 

 of the gases turned Into a liquid crust and in the course of, 



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