

138 ONTOLOGY. 



624. All the Earthy could not have been separated 

 from the water by the first storm of precipitation. For 

 the water now rested very much collapsed upon the 

 earth's nucleus, and could no longer therefore assume the 

 form of rain. That therefore which was now precipitated 

 could no longer be thoroughly crystallized, but must 

 follow the current and disquietude of the water, and 

 thus emerge from it in a slaty or massive condition. 



625. The quartz of the granite endeavours to set itself 

 free from the clay and talc, or it becomes freed by the 

 latter removing from it in virtue of its polar behaviour. 

 There is therefore one series of rocks, in which the 

 granite is constantly rejecting the feldspar and mica more 

 and more, and at last subsists as quartz simply, which 

 quartzose rocks as forming entire mountains are for intel- 

 ligible reasons not of frequent occurrence. 



626. The completion of the gneiss in its entire sepa- 

 ration from the granite, and the evolution of feldspar upon 

 a large scale constitutes the clay -slate, and finally clay- 

 stone and clay-porphyry. This yields us a new series of 

 formations, in which the gneiss gradually attains to being 

 divested of quartz and mica and to a pure position as 

 feldspar. The clay-slate is a true gneiss, that has lost the 

 definite particles of quartz and mica. 



627. The position of mica-schist constitutes in its 

 purity the talc-formation, talc-slate, chlorite- slate, horn- 

 blende-slate. 



628. After these several precipitations, the calcareous 

 mass remains behind in the water, and now, as in the 

 first periods of crystallization, is charged with carbonic 

 acid, and is precipitated as transitionary calx under the 

 form of mountain limestone. 



629. These formations are found upon the whole to be 

 arranged on the earth, in the order of time at which they 

 were precipitated from the water. In the middle of the 

 loftiest mountains is granite, then gneiss and mica-schist ; 

 then follow quartzose rocks, clay-slate or porphyry, 

 talcose rocks, and lastly on the edge of all these runs the 

 chain of alpine or mountain limestone. In the last of 



