THE REVIVED THEORY OF PHLOGISTON. 569 



alone and in its natural state. Viewed under the latter aspect, the terms 'fire,' 

 ' matter of the sun, of light, and of heat,' are specially appropriate to it. Under 

 such conditions, it is a substance which may he regarded as made up of infini- 

 tesimal particles, agitated by a very rapid and continuous motion, and hence 

 essentially fluid. This substance, of which the sun is, as it were, the general 

 reservoir, is emanating thence constantly, and is universally distributed through- 

 out all bodies known to us, though not as a principle, or as essential to their con- 

 stitution, inasmuch as we may deprive them of it at least in great measure 

 witbout their suffering the least decomposition in consequence. . . . Yet the 

 phenomena presented by inflammable substances in burning show that they 

 really contain the matter of fire as one of their principles. . . . Let us, there- 

 fore, investigate the properties of this fire which has become fixed, and en- 

 tered as a principle into bodies. To it we will specially assign the name of 

 'inflammable matter,' 'sulphur-principle,' and 'phlogiston,' to distinguish it 

 from pure fire." 



A;ain, much the same thins: is to be found in Baurae's " Manuel 

 de Chymie " (1765) ; as, for example: 



" TVe consider fire in two different states : when it is pure, isolated, and 

 forming no part of any compound .... when it is combined with otber sub- 

 stances, forming one of the constituent principles of compound bodies. . . . We 

 have no certainty whether or not fire possesses weight. There are experiments 

 pro and contra. . . . During the combustion of substances, combined fire is re- 

 duced to elementary fire, and is dissipated as the process goes on. The famous 

 Boerhaave, however, is not of this opinion ; he says that, were this the case, the 

 amount of elementary fire in Nature must increase ad infinitum. . . . But it is 

 easy to reply to this objection by saying that, as we have the right to presume, 

 the elementary fire discharged from bodies combines with other substances, and 

 that it loses all its properties as free fire on becoming a constituent principle of 

 bodies into the composition of which it enters. . . . The principle here spoken 

 of is that to which Stahl has given the name of phlogiston." 



In interpreting the above and other phlogistic writings by the 

 light of modern doctrine, it is not meant to attribute to their several 

 authors the precise notion of energy that now prevails. It is con- 

 tended only that the phlogistians had, in their time, possession of a 

 real truth in Nature which, altogether lost sight of in the intermediate 

 period, has since crystallized out in a definite form. "I trust," said 

 BeCcher, "that I have got hold of my pitcher by the right handle." 

 And what he and his followers got hold of and retained so tenaciously, 

 though it may be shiftingly and ignorantly, we now hold to know- 

 ingly, definitely, and quantitatively, as part and parcel of the grandest 

 generalization in science that has ever yet been established. 



