]202 M. BaoNGwiART on the position 



made by this geologist, and^vhich wa« comniunicated irt MS. 

 to me, he has noticed serpentine in the environs of Pietra- 

 mala and Corigliano ; but he gives no information respect- ^ 

 ing its position. 



I have stated, when speaking of the position of Mont«- 

 Ferrato, what M. Bardi has said, and I have cited Messrs 

 Faujas, Viviani, Mojon, and Holland, when mentioning the 

 serpentines of Monte-Ramazzo. 



M. Marzari Pencati, in a notice he has published in the 

 journal entitled, the Venetian Observer, for September and 

 October, 1820, on the superposition and discordant mode of 

 occurrence of granite on a secondary limestone, says a few 

 words on serpentines. He notices a serpentine vein traversing 

 the Alpine limestone at Canzocoli, and between Forno and 

 Predazzo, in the valley of Avizio. He speaks of the passage 

 of what he calls tertiary granite of three substances into ser- 

 pentine rock. I feel much flattered at still finding myself 

 of the same opinion with M. Marzari on this point. The 

 diallage rock, named granitone by the Italian geologists, 

 called diallage granite by M. Cordier, a perfectly crystalline 

 rock, which possesses no volcanic character, which contains 

 many of the elements of granites, occurring on a formation 

 as recent as that I have described, disposes one to admit with 

 less difficulty, the position of true granite on these same 

 rocks. I have seen this granite at M. Mazari's, and it ap- 

 pears to me altogether like that of Cherbourg. 



But there are two naturalists less read, even anterior to all 

 those I have cited, who have perceived this fact. — The first 

 is Ferber, who says, that there are reasons for believing 

 that the gabbro (serpentine) o/"fAe Imprunetta is placed on 



a limestone rock That it is a grey compact limestone^ 



■containing nodules of pyrites. The stale of science at the 

 time in which he wrote (1772), did not allow him to draw 

 any general conclusion from this observation. 



The second is M. Palassou, that naturalist of Pau, who 

 pursued to the end of a long life labours that evinced great 

 activity, patience, and information. He had observed in the 

 Pyrenees a rock, the charactersj determinatiouj and position 



