2 Mr. G. F. Rodwell on the Theory of Phlogiston. 



Phlogiston was not a new creation; possessing other names, 

 and endued with ill- denned and varying functions, it had been 

 conspicuous in many physical systems. The chief merit of 

 Becher and Stahl was that they extended its functions in one 

 direction, and conferred upon them a definitiveness which they 

 had hitherto lacked. The theory of phlogiston was not the 

 result of a sudden development, it did not owe its existence to 

 an intellectual exploit, but it arose by a process of evolution, 

 and by a gradual modus of development. 



Let us trace the course of that development. 



I. Of the " subtilis ignis " of the Ancients. 



The earliest physical theory of which we have any cognizance, 

 affirmed that the universe consists of four elements — fire, *air, 

 water, and earth. We have good evidence that this theory pre- 

 vailed prior to the fifteenth century B.C. ; indeed it seems pro- 

 bable that it originated before the separation of the Medo-Persic 

 and the Hindu branches of the Aryan family. Zoroaster appears 

 to have introduced element-worship among the Medo-Persic 

 races, and as he is supposed to have been a Scythian, it is pro- 

 bable that this form of worship originated with the Scyths. 

 In the ancient Brahmanical religion three gods, symbolized by 

 elements, were worshipped, and first in this trinity was Agni, 

 the god of fire. But while the Hindus adopted a polytheism, 

 the primitive Magism introduced by Zoroaster was developed 

 into a monotheism, and as fire was considered first and most 

 potent of the elements, it became the one visible symbol of their 

 god. The divinity was called " the one fire," " the first fire," 

 from whom proceeds " forjcfropov 7rvp," which diffuses itself 

 through all matter, and penetrates to the centre of the earth. 

 It was believed to be the principle of life ; and the soul was re- 

 garded as a very pure tire, indestructible, and eventually return- 

 ing to the original " first fire " — 



" OTL ^f%?7 TTVp $wdfjL€l TTCLTpOS OVO~a (fraLVOV 



aOdvaros tg /jLeyeo, koI £o>?5? SeanTOTa ecrrt"*. 



This belief pervades later philosophy. Thus Aristotle affirms 

 that some derive %r}v from ^eeiv because the soul is heat : — " Ot 

 fxev to OepfAov, Xeyovres on, 8ta tovto /cat to Iffiv (&v6\xacrTaC yj \. 

 Seneca says, "Nihil enim viveret sine calore^j. 



The potency of the Zoroastrian divinity was proved in the 



* Vide UarpiKiov to. tov Zcopoda-rpov \6yia. 

 f Uep\ Vvxrjs, lib. i. cap. 2. 

 X Quasi. Natur. lib. ii. cap. 10. 



