270 



ILLUSTRATIONS OF THE 



of whinftone 



kno 



n 



depth 



terfeding the ft 



to an un 



and moft probably, like oth 



communicating with the mineral region 



be doubted by any 



who has ftudied 



\ 



the fabjea of bafaltine rocks, through any other 

 medium than the volcanic theory. The rami, 

 fications which run from it into the calcareous 

 rock, contrived, Faujas fays, juft as if on purpofe 



to perpi 



alogifts, is one of th 



know 



well- 



and charaaeriftic appearances of bafal 



tic veins. 



241. It can hardly be doubted, that the lava 

 defcribed by the fame author as heavi 



mg up 



a mafs of granite*, and including pieces of 



a rock of real whinftone. The fame 



; and, though I 



It, 1 



may be faid of many others 



pretend not to affirm that there is nothing 



came m 

 decidedly 



[he Vivarais, I muft fay, that nothing 

 volcanic appears in the defcription of 



that country, but many things that are certainly 



of a very different origin. 



I 



the prefent ft 



f geological fc 



feilful mineralogift could hardly employ 



felf better, th 



m 



traverfing thofe ambiguous 

 countries, where fo much has been afcribed to 

 the ancient operation of volcanic fire, and mark- 

 ing out what belongs either clearly to the erupts 



ed 



K^4-^S 



^ Volcaiiis 



du Vivarais^ fol. p. ^6^^ &:c. 



■> 



^* 



