COSMOGONY. 



The science of cosmogony treats of the history of creation. 



Geology comprises that later portion of the history which is 

 within the range of direct investigation, beginning with the rock- 

 covered globe, and gathering only a few hints as to a previous state 

 of igneous fluidity. 



Through Astronomy our knowledge of this earlier state becomes 

 less doubtful, and we even discover evidence of a period still more 

 remote. Ascertaining thence that the sun of our system is in 

 intense ignition, that the moon, the earth's satellite, was once a 

 globe of fire, but is now cooled and covered with extinct craters, 

 and that space is filled with burning suns, — and learning also from 

 physical science that all heated bodies in space must have been 

 losing heat through past time, the smallest most rapidly, — we safely 

 conclude that the earth has passed through a stage of igneous 

 fluidity. 



Again, as to the remoter period : the forms of the nebulae and 

 of other starry systems in the heavens, and the relations which 

 subsist between the spheres in our own system, have been found to 

 be such as would haA^e resulted if the whole universe had been 

 evolved from an original nebula or gaseous fluid. It is not neces- 

 sary for the strength of this argument that any portion of the 

 primal nebula should exist now at this late period in the history of 

 the universe : it is only what might have been expected that the 

 nebulae of the present heavens should be turning out to be clusters 

 of stars. If, then, this nebular theory be true, the universe has 

 been developed from a primal unit, and the earth is one of the 

 individual orbs produced in the course of its evolution. Its his- 

 tory is in kind like that which has been deciphered with regard to 

 the earth : it only carries the action of physical forces, under a 

 sustaining and directing hand, further back in time. 



The science also of Chemistry is aiding in the study of the earth's 

 earliest development, and is preparing itself to write a history of 

 the various changes which should have taken place among the 

 elements from the first commencement of combination to the 

 formation of the solid crust of our globe. 



It is not proposed to enter either into chemical or astronomical 



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