APPENDIX. 



not only the orbicular granite, but also globular porphyry, 

 two of the most beautiful stones known to mineralogists. 



I had before heard from M. Dupeyrat, chief engineer des 

 ponts et chaussee.s in Corsica, a very good naturalist, that M. 

 Mathieu, a captain of artillery, had discovered large masses 

 of globular porphyry on their site. M. Dupeyrat was so 

 good even as to give me a handsome specimen of this stone 

 from M. Mathieu j but I was yet without the necessary in- 

 formation respecting the spot where it was found, to be able 

 to speak of it with certainty, when M. Mathieu, under orders 

 to join the army in Holland, came to Paris, where I had the 

 pleasure of seeing him, and receiving some very instructive 

 details, accompanied by plans and drawings, and a series of 

 very fine specimens of all the varieties of globular porphyry, 

 with which he was so obliging as to enrich my collection. 



My book was wholly printed, but the publication was de- 

 layed by the engravings not being yet entirely completed; 

 this delay allowed of my inserting the present account, as 

 well as that I have previously given of orbicular granite : the 

 learned among naturalists will be the better pleased with me 

 for producing it, as the basis of the account is derived from 

 M. Mathieu himself. 



It is fit however that I should observe, before I proceed 

 further, that a specimen of globular porphyry, nearly twenty 

 years back, was added to the collection of the beautiful cabi- 

 net of natural history in the Hotel de Monnaie at Paris, 

 formed by M. Sage, founder of the first School of Mines, a 

 ticket to which states that it came from Galeria, in Corsica 5 

 but whether this single specimen wholly escaped the notice 

 of mineralogists ; whether it was regarded merely as a sort 

 of solid geod, formed accidentally in the composition which 

 serves it as a gang, this species of stone was no longer 

 spoken of, and no specimens of it were found in other ca- 

 binets. 



In the month of January, 1806, M. Rampasse, a veteran 

 officer of Corsican light infantry, favoured me with informa- 

 tion from Bastia that, in a mineralogical excursion into the 



