CH. I. PYTHAGORAS ON GEOLOGY. n 



He was the first to assert that the earth is not fixed, but 

 moves in the heavens ; but he did not know that it moves 

 round the sun. He also discovered that the evening and 

 morning star are the same planet ; the early Greeks called 

 this planet Phosphorus, and it did not receive the name of 

 Venus till some time afterwards. 



Some of the most remarkable truths taught by Pytha- 

 goras were about geology, or the study of the earth. He 

 noticed that seashells were sometimes to be found far inland 

 imbedded in solid ground in a way that showed they were 

 not brought there by man. Therefore, he argued that to 

 bury .fttt-shells in the rocks, the sea must once have been 

 there. He had also probably watched the sea eating away 

 the cliffs on the shores of Italy, as you may see it doing 

 now on the shores of Norfolk and Suffolk ; and when he 

 was in Egypt he must have seen the Nile carrying mud and 

 laying it down at its mouth, or delta, to form new land. 

 From all these and other observations he, and his pupils 

 who followed him, drew some very true conclusions which 

 are given in Ovid's Metamorphoses : 



1. Solid land has been converted into sea. 



2. Sea has been changed into land. Marine shells lie 

 far distant from the deep. . 



3. Valleys have been excavated by running water, and 

 floods have washed down hills into the sea. 



4. Islands have been joined to the mainland by the 

 growth of deltas and new deposits, as in the case of Antissa 

 joined to Lesbos, Pharos to Egypt, etc. 



5. Peninsulas have been divided from the mainland and 

 have become islands, as Leucadia : and according to tradi- 

 tion Sicily, the sea having carried away the isthmus. 



6. Land has been submerged by earthquakes; the 

 Grecian cities of Helice and Buris, for example, are to be 

 seen under the sea, with their walls inclined 



