15 
substances, ■which had undergone the process of petrifaction, had 
not, in those ages, escaped observation. 
Xenophanes, the founder of the Eleatic sect, who wrote upwards 
of 500 years before Christ, maintained that God and the world were 
the same ; and contended for the eternity of the universe. In sup- 
port of the latter opinion, he dwelt much upon the circumstance of 
petrified shells being found, in the internal parts of mountains, and 
in the bowels of the earth. He related, that, in the quarries of Sy- 
racuse, the impressions of the fishes existed ; that the impression of a 
small fish was found, deeply imbedded in a rock at Paros ; and, that 
almost every species of marine animals had been thus preserved ; 
he inferring, from the appearance of these extraordinary phenomena, 
that these places must, in very distant ages, have been covered 
with the sea*. 
Herodotus, who wrote 440 years before Christ, speaks particu- 
larly of shells existing in the mountains of Egypt; and concludes, 
from this circumstance, and the saltish emanations which injured 
the pyramids, that the sea had gradually retired from these partsf . 
Theophrastus was supposed to have written a book, entirely on 
petrifactions, and which, though ranked amongst his lost works, was 
imagined to have been in the possession of Pliny; and to have 
yielded him some portion of assistance, in that part of his Natural 
History. 
Eratosthenes, who lived 200 years before Christ, when inquiring 
into the figure of the earth, also considered it as a question worthy 
of investigation — How it could have happened, that vast numbers 
of oyster, and other shells, should be found scattered in many 
places at a very considerable distance from the sea. This phenome- 
non had also been noticed by Strabo, and by Xanthus of Lydia, as 
well as by Strabo himself ; who refers to and corroborates their re- 
marks in the first book of his Geography ; particularizing some of 
* In Originis Philosophumenis, cap. xiv. p. 100. f Lib. ii. sect. xii. 
