?^4 



ILLUSTRATIONS OF THE 



ock agrees,, in many refpeds, and fo does their 

 chemical analyfis ; but their difpofition and ar- 

 rangement are fo diffimilar, that they cannot be 

 fuppofed to be of the fame formation. 



* ■ 



37. This argument, I believe 



firftfta 



ted by Mr S 



th 



in a letter to Sir J 



publifhed in the 65th volume 



Pbilofophical Tranfa6l 



Th 



of 

 intelli- 



gent obferver, after vifiting the countries in Eii- 

 rope moft remarkable either for burning, or for 

 what are accounted, extinguiftied volcanoes, and 

 examining them with a very difcriminating eye, 

 remained convinced, that there are two diftind 

 fpecies of rock, which both owe their 



fi 



fit 



but to fire ading in 

 3 extremely differen 



common volcanic lava 



-ir origin 

 circumftances and 

 ;. The firfl is the 

 ther, to which he 



* 



gives the name of a bafaltine rock, comprehends 

 fuch rocks as the Giant's Caiifeway, the bafaltes 

 of the Vivarais, of the Euganean Hills, &c. and 

 differs in nothing from that which is called here 



by th 



name of whinil 



M 



Strange con- 



ceived, that the one of thefe kinds of flone could, 

 no more than the other, be accounted the work 



b 



of aqueous depoiition, but was led to the diflinc- 

 tion jufl mentioned, by obferving the organization 



d 



an 



/ 



i 



Account of Two Giants Caufeways in the Vene- 

 tian State, &.C. by John Strange, '£% Phil. Tranf. 

 vol. Ixv. (1775.) P- 5; &c. 



