ON THE CRYSTALS IN LAVAS. g40 



is filled throughout its whole extent, from the extremity of 

 its destructive course to the place where it issued from the 

 crater, with a multitude of pyroxene schoerls, of those 

 whitish crystalline laminee I have described, and of small 

 chrysolites ; and. the crater, from which it issued, threw 

 up myriads of the same substances. Can we discern here 

 formations produced at the time of the cooling of this lava, 

 since all these crystals existed there at the moment of its 

 greatest fusion and heat, the focus of the eruption itself 

 Iiaviug- thrown up loose ones from its crater in multitudes 

 innumerable } 



The naturalists who have remarked, that leucites and Leucites and 

 pyroxene schoerls are crystals not to be found in the strata pyo^en^ not 



r •' , . - _ ^ iound \n the 



commg under our observation ; and who have hence infer- strata we have 



red, that they would have remained for ever unknown to penetraied,but 



, ■ . . 'C3me from 



US, if volcanic eruptions had not brought them to light ; otheis beneath. 



are certainly well founded in their opinion. Mr. Fl. de Eel- 

 levue however terms it a supposition. But nothing is more 

 true than the observation, and. nothing can be more natural 

 than the consequences deduced from it. 



" We have seen," continues he, "that there is no ex- Rocks of the 

 ample to prove, that aqiieous solutions now form, or are P"'ni'"ve kiod 

 , , r. r- ■ 1 • -I 1 ... , not now form- 



capable or Tormmg, rocks similar to the primitive ones; and ed Ln water: 



that fire on the contrary daily exhibits to us producdons, 

 that are not simply analogous, but even identical with ' 

 them." 



On the contrary we have seen, that the productions of 

 fire have only an apparent, not a real resemblance to pri- 

 mitive, or, to speak with more accuracy, primordial rocks. ♦ 

 The fires of volcanoes, like those of our furnaces, have 

 not produced and never will produce any tning like them, 

 because these primordial strata do not owe their origin to 

 fire. 



Neither will aqueous solutions form such rocks; for they because their 

 were produced by precipitation from the primordial fluid wh'i'ch' e*x!<,ted 

 at periods not remote from the origin of the globe, and in the primi- 

 every thing indicates, that they no longer continue to be j^^o'^jon^* *'* 

 formed. The water of the present sea does not now con- found in th^ 

 tain the requisite elements, for of these it has been de- ^'^^' 

 prived. The mud of rivers, of which some imagine they The deposi- 



uiay 



