APPENDIX. 615 



that an insulated block of stone, the organisation of which 

 possessed a character so forcibly pronounced and so different 

 to that of other rocks, might, if the spot where it was found 

 were discovered, point out the distance it had traversed from 

 its native place to that whither it was removed in the shape 

 of a rounded block. 



Messieurs de Sionville, Barral, Dolornieu, and other natu- 

 ralists after them, made long and vain researches to discover 

 the orbicular granite in its original situation. The search 

 for it seemed to be abandoned, and specimens of the first 

 block, dispersed in cabinets, became every day more and 

 more rare -, and when any pieces of it were exposed to sale, 

 they obtained very considerable prices. 



In the month of May 1809, that is to say, twenty-four 

 years afterwards, M. Mathieu, a captain of artillery resident 

 in Corsica, distinguished alike for his military talents and 

 his taste for the study of nature, while traversing the steep 

 granitic mountain by the side of the village of Saintc Lucie, 

 seven leagues distant from the spot where the first block was 

 found, observed attentively a saliant mass of rock, entirely 

 covered with lichens and moss, which concealed its external 

 character 5 but the interior texture of the stone being acci- 

 dentally displayed by a break in it, M. Mathieu was agreeably 

 surprised to find that the whole mass consisted of orbicular 

 granite, similar in composition, colour, and mode of forma- 

 tion, to the orbicular granite which had so long and fruit- 

 jlessly been sought : other masses, contiguous one to the 

 1 other, and in a similar manner covered with lichens and old 

 jmoss, occasioning a presumption that they might be of like 

 Inature, M. Mathieu tried them with his hammer, and dis- 

 icovered them to be actually the same species of orbicular 

 granite. It was about three parts up the mountain, and on 

 ground belonging to M. Jean Paul Roccasserra, that this dis- 

 covery was made. 



As the point the most essential to geology here is to ascer- 

 :ain distinctly the spot where this granite lies, that no doubt 

 nay be entertained of its adherence to the rock on which it 



