ST. AUGUSTINE ON THE MAGNET. 89 



which he will not vouch, lasted for fifteen centuries. The 

 caution is characteristic of the author, who, at seventy 

 years of age, reviewed all his writings and retracted that 

 which appeared doubtful or extravagant, and sought to 

 harmonize his opinions where they seemed in conflict. 

 Elsewhere he is careful to distinguish between matters of 

 hearsay and things which he knows or which can readily 

 be tested, and among these last he includes quicklime, 

 which burns in water and remains cold in oil, and the 

 magnet; and then he says that he does not know by what 

 imperceptible potion the lodestone refuses to move straws 

 and yet snatches the iron. 1 



That was a significant question. It marks the first 

 dawning notion of some possible difference between amber 

 attraction and magnet attraction. Why should the lode- 

 stone move iron, and yet be powerless to stir the light 

 chaff? Why should the amber draw the chaff, and yet be 

 unable to attract iron? The querist believed the resin and 

 the stone to be generically the same. Hence, the anomaly 

 which surprises him. The Chinese Kouopho who said, a 

 century earlier, that the amber and magnet effects were 

 inexplicable, had not perceived that the mustard seeds 

 which flew to the amber refused to obey the call of the 

 stone. 



When this difference was suggested, then the rise of 

 electrical knowledge, in human thought, began to move 

 in parallel channels. The world waited for a dozen cen- 

 turies before finally recognizing the distinction and sepa- 

 rating the phenomena into those which were electric or 

 amber-like and those which were lodestone-like or mag- 

 netic ; but the first suggestion of it came, none the less, 

 from the great philosopher and saint of the early church. 



It may appear singular that St. Augustine should have 

 referred to the mystery of the magnet and amber, not in 

 any metaphorical way, but in the form of statement of 

 actually-observed physical fact. Yet, on the other hand, 



1 De Civ. Dei, lib. 21, c. vi. 



