[ ^^6 ] 



Dolomieu. Not having had the happinefs of viewing thofe flu- 

 pendous torrents, I founded my opinion on the accounts given by 

 the moft accurate obfervers, and particularly of Citizen Dolomieu 

 who beheld and carefully examined every circumftance relating to 

 them for many years. This great obferver has not thought my 

 opinion fo inconceivable, for he has fince embraced it ; " from the 

 " manner, fays he, in which lavas flow, it cannot be doubted 

 " but they carry with them a fubftance capable of maintaining 

 " their heat and fluidity, and contain a fubflince which burns in 

 " contad with the atmofphere until it is confumed. This fub- 

 " ftance, of which fulphur is at leaft one of the principal ingre- 

 " dients, if it be not the only one, bears a ftrong refemblance in 

 " its conftitution to phofphorus, being capable of two forts of 

 " combuftion. This combuflion feems capable of maintaining 

 " fluidity in a bed of lava, &c." i New Rozier's Journ. p. 119 

 and I20- 



Sir James fays I have fuppofed fubftances that have left no 

 trace of their exiftence. Other obfervers however difcovered thefe 

 traces, as Dolomieu and Fabroni in the pafl'ages I have already 

 quoted. Mineralogy, vol. i. p. 397, and i New Roz. p. 120, 

 121. It is not to be expeded that volatile fubftances, fuch as 

 fulphur and petrol, fhould long remain. 



However, 



