dN THE CRYSTALS IN LAVAS, g5 J 



^reait exaggeration. Many are seen in various places, no 

 doubt ; but the space they occupy bears no compar'son with 

 that where there are none. I include ancient and extinct 

 volcanoes, for those still burning are very few. There are Burning ones 

 Only four in Europe: those of Iceland are in a distant lati- ^^'"^ "■'^• 

 tude. 



This renninds me of a similar opinion of Mr. Patrin, Pairings misre- 

 which he gave of Italy. It is in his Rechercltes sur les Fo - i','^']'!^ "n^th^ ° 

 cans, " Inquiry concerning Volcanoes according to the respect. 

 Principles of the pneumatic Chemistry." He says, " Italy 

 is full of volcanoes, and covered from one end to the other 

 with lavas and tufas of enormous thickness." Yet the true fact 

 with respect to Italy is, that the Apennines, which traverse 

 it from one extremity to the other, all the ramifications of 

 that chain, and all the eastern shore of that peninsula, have 

 nothing volcanic in them ; and that the soil of this kind lies 

 only on the western coast, where it is frequeutly interrupted 

 by aqueous strata. 



When explanations of the manner, in which a fact in ter- When people 

 restrial physics, that is in some decree obscure, may have ^•^'■"^'^'^ [""""^ 



•l J 1 • c 1 , • nature tliey 



happened, deviate from the most natural, and that which often supnort 



is most conformable to all the phenomena, they may be ''^*^ ^^''^ °'^^' 



^ . iiion by con- 



very different from each other, or even opposite. Thus it tiadktory ar- 



Jiappens, that the naturalist I have just quoted, being g^'ii"-"-** 

 equally of opinion, that the pyroxene schoerls did not pre- 

 exist in the lava, separates them from the matter of the lava, 

 and makes them arise " from an aeriform fluid, which has 

 passed to a solid consistence by the effect of attraction." 

 This question I have already discussed with precision, and 

 to some extent, founding all I have said on facts, in my Ob- 

 servations on Pyroxenes, or volcanic Schoerls, in the Jour- 

 nal de Physiqiie for March, 1801. 



From all the facts I have adduced the following conclu- General con- 

 eions may be considered as established. elusions. 



That every volcano, whether burning, extinct, or ancient, Volcanic 



whatever its height or extent, and wherever situate, is a ?^°^'"^fl"^£. 

 » ' ' fi)rm:-(iby fire, 



mountain of a class distinct from all others: that it is imd dfiVrent 

 formed by no neptunian strata : that all the solid substances f fo'" all oihcrs. 

 constituting it are the products of fire : that it has been 

 raised up, from its base to its summit, by the accumulation 



of 



