ROCKS. Ii03 



formation. In Attica, in the island of Euboea, and in the 

 Peloponnesus, it has been remarked, " that the limestone, 

 when superposed on mica slate, is beautiful and crystalline in 

 proportion to the purity of the latter substance and to the 

 smallness of its argillaceous contents ; and, as is well known, 

 this rock, together with beds of gneiss, appears at many points, 

 at a considerable depth below the surface, in the islands of 

 Paros and Antiparos."* We may here infer the existence of 

 an imperfectly metamorphosed flotz formation, if faith can be 

 yielded to the testimony of Origen, according to whom, tho 

 ancient Eleatic, Xenophanes of Colophont (who supposed the 

 whole earth's crust to have been once covered by the sea), de- 

 clared that marine fossils had been found in the quarries of 

 Syracuse, and the impression of a fish (a sardine) in the deepest 

 rocks of Paros. The Carrara or Luna marble quarries, which 

 constituted the principal source from which statuary marble 

 was derived even prior to the time of Augustus, and which 

 will probably continue to do so until the quarries of Paros 

 shall be reopened, are beds of calcareous sandstone macigno 

 altered by Plutonic action, and occurring in the insulated 

 mountain of Apuana, between gneiss-like mica and talcose 

 schist. $ Whether at some points granular limestone may 

 not have been formed in the interior of the earth, and been 

 raised by gneiss and syenite to the surface, where it forms 

 vein-like fissures, is a question on which I can not hazard 

 an opinion, owing to my own want of personal knowledge of 

 the subject. 



* Leop. von Bach, Descr. ties Canaries, p. 394 ; Fiedler, Reise durch 

 dag Kdnigreich Grieckenland, th. ii., s., 181, 190, und 516. 



t I have previously alluded to the remarkable passage in Origen's 

 Philosophumena, cap. 14 (Opera, ed. Delarue, t. i., p. 893). From the 

 whole context, it seems very improbable that Xenophanes meant an 

 impression of a laurel (TWXOV dufvee') instead of an impression of a fish 

 (TVTTOV a^v^f). Delarue is wrong in blaming the correction of Jacob 

 Gronovius in changing the laurel into a sardel. The petrifaction of a 

 fish is also much more probable than the natural picture of Silenus, 

 which, according to Pliny (lib. xxxvi., 5), the quarry-men are stated to 

 have met with in Parian marble from Mount Marpessos. Scrvim ad 

 Virg., JEn., vi., 471. 



\ On the geognostic relations of Carrara ( The City of the Moon, Strabo 

 lib. v., p. 222), see Savi, Osservazioni sui terreni antichi Toscani, ir 

 the Nuovo Giornale de 1 Letterati di Pisa, and Hoffmann, in Karsten'i 

 Archiv far Mineralogie, bd. vi., s. 203-263 as well as in ki&'Geogn 

 Reise durch Italien, s. 244-265. 



$ According to the assumption of an excellent and very experiencet 

 observer, Karl von Leonhard. See his Jahrlmchfur Mi leralogie, 1834 

 s. 32P, and Bernhard Gotta, Gcognosie, s. 310. 



