390 Mr. Tennant o« Native Boracic Acid. 



Mr. Horner afterwards Informed me, that the late Dr. Men'ish of 

 Chelmsford had presented to the Geological Society a specimen 

 which he had received, with some other volcanic productions, from 

 Sicily, but which had been collected in the Lipari Islands ; the box 

 containing them being marked " Produ%ioni Volcan'iche Raccolte 

 ** nelle hole Eolie da Gitis. Lazzari — Lipari.'''' He found it to consist 

 of boracic acid, and it perfectly resembled that I have just described, 

 having the same yellow colour from an admixture of sulphur, and a 

 similar crust of this substance adhering to one side. 



Any future traveller visiting those countries would do well to exa- 

 mine them with a view to this particular object. The boracic acid 

 may be a more extensive volcanic product than has hitherto been 

 Imagined ; for in the account given of Its discovery some years ago by 

 Messrs. Hoefer and Mascagni, near Monte Rotondo, to the west of 

 Sienna, we can have no doubt of Its volcanic origin in those places, 

 IVom the substances which are there described to accompany it. 



