MODE III. BASALTIN. 65 



Cc We shall give a third opinion upon the ori- Brongniart's 

 gin of basalt, in a medium between the two pre- 

 ceding ones, and which appears to us the most 

 probable. The naturalists who profess it, as 

 Fortis,Dolomieu, Delrio, Spallanzani, think that 

 the discussion on basalt is often a dispute of 

 mere words : that if this name is given to those 

 stones whose characters we explained at the be- 

 ginning of this article; some are truly volcanic, 

 while others have entirely an aqueous origin; 

 that the basalts of Saxony, and those of Ethiopia, 

 certainly belong to this second division, and that 

 it is probable that those of Scotland and Ireland 

 also belong to it ; while those of Italy, and Au- 

 vergne, should be arranged in the first class to- 

 tally, or at least in part. 



"Other naturalists, and particularly M-Patrin^ 

 imagine that basalts are the productions of the 

 muddy eruptions of submarine volcanoes 5 and 

 that the nature of the eruption, and the influence 

 of the water, have given to this lava those par- 

 ticular characters for which it is remarkable. 

 They believe that the latter influence prevented 

 the basaltic matter from calcining or burning 

 those substances on which it flowed. This hy- 

 pothesis, which seems one of the most probable, 

 if not applied without exception to all basalts, 

 explains well enough the alternation of beds of 



VOL, i. F 



