Mr. G. F. Rod well on the Theory of Phlogiston. 21 



appears to be known about him ; and the accounts vary consider- 

 ably. He appears to have been appointed Professor of Medi- 

 cine in the University of Mayence in 1666, and subsequently 

 Physician to the Elector of Bavaria. In 1680 he went to 

 England and spent two years among the mines of Cornwall and 

 of Scotland; he died in 1682. 



The works of Becher which most concern us are the fol- 

 lowing : — 



Physica Subterranea, published in 1669. 



Supplementum Primum in Physicam Subterraneanly 1671. 



Supple mentum Secundum in Physicam Subterraneam, 1675. 



Minera Arenaria Perpetua, sive Supplementum Tertium in Phy- 

 sicam Subterraneam, 1680. 



The dedication of this last work is dated from London, aud is 

 sufficient answer to those who affirm that Becher never went to 

 England. 



The writings of Becher are most barbarous in style ; but it is 

 just to add that he apologizes for this, ending his apology with 

 the sentence, "sic rebus attentus, verba neglexi," which is fully 

 justified. The style and diction are not alone deficient, for the 

 matter itself is most obscure and unintelligible ; there is great 

 want of definiteness of expression, and some passages appear to 

 actually contradict others : a notable example of this is to be 

 found in the accounts which are given of the nature of mercury 

 (a) in the Physica Subterranea, (/3) in the Concordantia Chy- 

 mica, and (7) in the Supplementum Secundum. I cannot pro- 

 mise to faithfully interpret the ideas of Becher (for Stahl him- 

 self, living at the same period, and recognizing Becher as his 

 master, sometimes expresses doubts as to the precise meaning of 

 certain passages) ; but I have endeavoured as far as possible to 

 separate the intelligible from the occult portion of his writings ; 

 and after so doing there does appear a very sensible consistency 

 in regard to the greater number of major points. 



Becher considered water and earth to be the primal elements, 

 and he divided the latter into three kinds — (a) Vitrifiable earth, 

 (|S) inflammable earth, and (y) mercurial earth. These have been 

 regarded as specifically different from, and incapable of being 

 compared with, the elements of any previous physical system ; but 

 I cannot fail to recognize in them, under other names, the three 

 chemical principles sal, sulphur, mercurius-, and this being ad- 

 mitted, the system of Becher is a priori assimilable with the four- 

 element system. Let us then assimilate Becher's theory with the 

 three- element theory of the chemists, and regard the " vitrifiable 

 earth " as salt (the principle of fixity and solidity), the " inflam- 

 mable earth " as sulphur (the principle of combustibility), and 

 the " mercurial earth " as mercury (the principle of volatility). 



