GEOLOGY. 31 3 



Strata. 



When the position of the beds of transition rocks 

 are examined on a great scale, they are found to oc- 

 cupy immense hollows in the primitive rocks. Old 

 red sandstone fills up the hollows of the transition, 

 and occasionally of the primitive. The independent 

 coal, chalk, gypsum, and alluvial deposits fill up the 

 other hollows, and the process is still going on. 



In a depth of less than five hundred yards, eighty 

 different strata have been counted. 



Aqueous Origin. 



The formation of quartz, chalcedony, and calcare- 

 ous spar, may be witnessed, the last with great ra- 

 pidity, both by infiltration, and by solutions of carbo- 

 nate of lime. Chalcedony is produced in the first 

 way, quartz in both. 



The Wernerlan or Neptunian Theory. 



Werner's theory assumes as a first principle, that 

 our globe was once covered with a chaotic compost, 

 holding either in solution or suspension the various 

 rocks and strata which now present themselves at its 

 exterior crust. 



This fluid is supposed first to have deposited such 

 bodies as it held in chemical solution, by which pro- 

 cess a variety of crystallized rocks (such as granite, 

 &c.) were formed. In these no vegetable or animal 

 remains are found, not even rounded pebbles ; but in 

 the strata which lie on the crystalline, shells and 

 fragments occasionally occur, inconsequence of which 

 they have been termed transition strata, and it is 

 conjectured that about this time began the peopling 

 of the ocean. 



The waters of the earth now began to subside 

 more rapidly, and finely divided particles were de- 

 posited upon the transition rocks, chiefly in horizontal 



