On GRANITE. 83 
* Corfe*; peut-étre y trouvera-t-on quelque jour des to- 
* pafes.”’ 
M. PATRIN has reprefented this fpecies of cryftalization in 
a different light from that by which I had endeavoured to ex- 
plain the appearance of this ftone. He confiders the quartz as 
cryftalizing in its natural hexagonal fhape, and thus including 
bodies of feld-fpar; whereas I think that it is the fparry ftruc- 
ture of the laft that had induced a certain form upon the quartz, 
a form which is neither the natural fhape of the cryftalization 
of that filiceous fubftance, nor an accidental fhape, that had 
arifen from preceding caufes, but a fhape determined by the 
concretion of this mixed body cryftalizing from the fluid ftate 
of fufion. Indeed, I fee nothing in the fpecimens which we 
poffefs, that can juftify M. Parrin’s fuppofition ; on the con- 
trary, almoft every appearance is inconfiftent with it. I fhall 
mention only one. 
Ir the figuring caufe, which proceeds longitudinally through 
the ftone, were that of the filiceous cryftalization, then the 
tranfverfe fection would exhibit hexagonal figures of quartz, 
inclofing bodies of feld-fpar. Now, M. Parrin fays, that fe- 
veral of thofe fides of the hexagons are wanting; but then 
what remains fhouldbe conformable to that hexagonal figure of 
which it was a part. This, however, I think, is not the cafe; 
_and in the fpecimens which I have, the rhombic angles of the 
feld-fpar feem fo prevalent in the figures, and thefe Hebrew or 
rather Runic characters are fo regularly dire@ted by two lines 
correfponding with the rhombic angle, that I cannot help 
afcribing this regular figure to that caufe, and not confidering 
it as produced by the obtufe angles of imperfect hexagons. I 
L2 is 
* I am inclined to believe that this fpecimen, Which is here reprefented as coming 
from Corfica, is no other than the granite of Portfoy which I have defcribed. I imagine 
that here is only a graphic error, in writing de Cor/é, in place of d’Ecoff. 
