248 Wernc?- acconl'mg to Cuvicr. 



the distinctness of the crystalline grain is diminished. Serpen- 

 tines, porphyries, and traps succeed, in which this grain is still 

 less distinct, although the siliceous nature of these rocks evinces 

 the returning purity of the deposition. Intestine agitations in 

 the fluid destroy a part of these primary deposites : new rocks 

 are formed from their debris united by a cement. It is amidst 

 these convulsions that living nature arises. Carbon, the first of 

 these products, begins to shew itself. Coal, a mineral formed 

 from vegetables, appears in vast quantities. Lime, which had 

 already been associated with the primitive rocks, becomes more 

 and more abundant. Rich collections of sea-salt, to be one day 

 explored by man, fill iiTimense cavities. The waters, again tran- 

 quillized, but having their contents changed, deposite beds less 

 thick, and of greater variety, in which the remains of living 

 bodies are successively accuvmlated, in an order not less fixed 

 than that qfthe rocks xvhich contain them. Finally, the last re- 

 treat of the waters diffuses over the land immense collections of 

 alluvial matters, the first seats of vegetation, of cultivation, and 

 of social life. The rents in the strata formed during these con- 

 vulsions become filled with rocks of various kinds, as granite, 

 trap, &c., thus forming veins or dikes. The metals, like the 

 rocks, have had their epochs and their successions. The last of 

 the primitive, and the first of the secondary rocks, have re- 

 ceived them in abundance. They become rare in countries of 

 later formation. Commonly they are found in particular situa- 

 tions, in those veins zchich seem to be rods produced in the 

 great rocky masses, and zohich have been filled after their for- 

 mation. But they are not all of equal age. Those which have 

 been last formed are easily known, because their veins intersect 

 those of the more ancient, and are not themselves intersected. Tin 

 is the oldest of them all ; silver and copper are the latest formed. 

 Gold and iron, those two masters of the world, seem to have been 

 deposited in the bowels of the earth, at all the different epochs 

 of its formation ; but iron appears at each epoch under different 

 forms, and we can assign the age of its different ores. 



The necessity of abridging, obliges me thus to unite under 

 one view, results which we can easily imagine could only have 

 been obtained by many thousand observations. But Werner 

 made all these observations with so much care ; he combined 

 them with such scrupulous correctness, that all those which 



