Geologic Changes. 309 



ginning and close of the natural day, "evening" and 

 "morning;" and these terms do not seem in any 

 ct to limit or explain the word "day." 



But it is to be borne in mind that Moses speaks 

 of three efore he represents the sun as taking 



his place in the heavens to divide the clay from the 

 >m which it seems almost self-evident 

 that an ordinary day could not possibly be meant by 

 him. 



plain that chemistry is the only science that 

 can ide us in unravelling the first day's 



wo: oduction of light ; and it is 



mainly that we are to trace the 

 II further, until we find in the sediment- 

 ary KK k HOC of the mechanical action of water. 

 And what would be the changes which must have 

 occurred after the mingling and union of the ele- 

 ments which we have described as the first epoch 

 or d ration ? 



We know well what changes must have occurred, 

 if the laws of matter were the same then as now. 

 As heat was radiated from the glowing earth into 

 space, the whole mass was gradually cooled, until 

 the materials of which the rocks are composed be- 

 came simply a melted ball ; the air, the waters of 

 the earth, and all volatile substances, still forming a 

 dense cloud around its whole surface. Still later a 

 crust was -formed upon this globe by cooling, and 

 waters were condensed upon it, covering the entire 

 globe. For continents and mountains were impos- 

 sible till the crust in after ages became thick enough 



