ANCIENT SCIENCE. 17 



reans placed fire, as the watch-tower or outwork of Zeus, and about 

 this central fire they supposed that ten bodies revolved ; namely, the 

 earth ; another earth (avnxBov) opposite to this, making day and night; 

 the sun which reflected the central fire ; the moon ; the five planets ; 

 and the starry sphere. 



Some of the Pythagoreans appear to have clearly observed evidences 

 of those changes on the surface of the earth which it belongs to the 

 science of geology to consider. The Roman poet Ovid, who wrote 

 many centuries after the time of Pythagoras, has introduced into the 

 fifteenth book of his " Metamorphoses" a sketch of the doctrines of the 

 Pythagoreans. Pythagoras himself is here represented as speaking in 

 his own person, although it is evident that some of the illustrations 

 put into his mouth refer to events that occurred after his age. We 

 quote, from Addison's translation, a few lines describing geological 

 phenomena : 



The face of places and their forms decay, 

 And that is solid earth which once was sea ; 

 Seas in their turn retreating from the shore, 

 Make solid land what ocean was before ; 

 And far from strands are shells of fishes found, 

 And rusty anchors fixed on mountain ground. 

 And what were fields before, now washed and worn 

 By falling flood, from high to valleys turn, 

 And crumbling rtill descend to level lands ; 

 And lakes and trembling bogs make barren sands. 

 The parched desert floats in streams unknown, 

 Wondering to drink of waters not her own. 



He then gives examples of streams having changed their courses and 

 their characters, naming among historical instances of sea changes : 



Antissa, Pharos, Tyre, in seas were pent, 



Once isles, but now increase the continent : 



While the Leucadian coast, main land before, 



By rushing seas is severed from the shore. 



So Zancle to the Italian earth was tied, 



And men once walked where ships at anchor ride, 



Till Neptune overlooked the narrow way, 



And in disdain poured in the conquering sea. 



Two cities that adorned the Achaian ground, 



Buris and Helice, no more are found ; 



But, whelmed beneath a lake, are sunk and drowned, 



And boatmen through the crystal waters show 



To wondering passengers the walls below. 



The' reader will not fail to remark how distinctly the occurrence of 

 fossil shells, etc., is pointed out in Ovid's lines. Such phenomena 

 were, indeed, known to several of the early Greek philosophers, and 

 were discussed by them. Thus, we know that the remains of marine 

 animals embedded in rocks in inland situations attracted the atten- 

 tion of Xenophanes, who flourished about five centuries before the 

 Christian era. 



The name of LEUCIPPUS (c. B.C. 495 428 ?), of Abdera, an Ionian 



