OF COMMON SALT. 



101 



glimpse, even though an imperfect one, at its previous 

 condition. It is considered certain, by astronomers and 

 geologists, that, in the earliest Azoic period of creation, the 

 temperature of the earth was so high that it formed a molten 

 mass, and all volatile bodies, or those capable of being converted 

 into vapor at high temperatures, surrounded the globe as an 

 atmosphere ; that the ocean literally boiled, and hot steam 

 mixed with the other atmospheric vapors. We may imagine 

 sodic chloride to have existed in the gaseous state at this 

 period. There can be little doubt about the sodium element 

 having so existed, since by the aid of the spectroscope we 

 see it in the atmosphere of the sun and those stars, as 

 Aldabaran and Betelgeux, which have been carefully 

 examined. There is some doubt about chlorine, since it 

 hardly exists, as such, at higher temperatures than 800° C. 

 The recent experiments of Victor and Carl Meyer, of Zurich, 

 show that it diminishes in density up to 1,200° C, at which 

 point it is about T62, and increases in volume one-half, 

 becoming alotropic. Be that as it may, however, with the 

 gradual fall of temperature, sodic chloride would form, and 

 deposit upon the surface of the land and water : and as the 

 cooling process continued, the aqueous vapor would condeDse 

 and fall upon the earth in the shape of rain, which would 

 dissolve and wash out all the salt into the sea. In the end 

 the sea would gradually lick up and appropriate, by constant 

 interchange of elements, rising clouds and falling rain, all 

 the soluble salts on the face of the earth, except those 

 protected by insoluble coverings. And so the sea wouid 

 become the great reservoir of soluble salts that we find it, as 

 stated in the beginning of this paper. 



Before leaving this part of the subject let me draw atten- 

 tion to the remarkable provision of nature which places 

 gypsum, one of the least soluble of rocks, uniformly as a 

 covering over sodic chloride, one of the most soluble, as, to 



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