4 Dr. E. J. Mills on the First Principles of Chemistry. 



modern geology or mathematics, but continuity ; or of bio- 

 logy, but evolution ? The greatest generalization of the prac- 

 tical consciousness is worthy to become our chief criterion and 

 lay our fresh foundation. 



(5) We have then to select those derived forms of the idea 

 of motion which, lying nearest to it, are yet within the pro- 

 vince of chemistry. One of these must necessarily be action, 

 because the chief business of chemistry is a kind of work. 

 Chemical substances are valued, not for what they are con- 

 ceived as being, but as doing ; and the first question we ask 

 about a body is, What is its function ? alcoholic, saline, ke- 

 tonic, zincous, chlorous ? in other words, How does it behave 

 with this, that, or the other reagent ? And it is made, bought, 

 and sold for its use. 



One objection that might be made here ought perhaps to be 

 answered at once. It may be said that substances have a being 

 in themselves — namely, a " constitution," as it is technically 

 termed — that their constitution consists in the arrangement of 

 atoms, of which they are in reality made. Whether this is 

 the case or not, shall be in due course examined. I content 

 myself with remarking that constitution has been, and always 

 is, considered of very small importance in comparison with 

 action, — the two standing to each other in the relation of spe- 

 culation and experiment. A moment's consideration of parti- 

 cular cases will show this. Indigo, sugar, salt, and alcohol 

 were extremely valuable before any thing whatever was asserted 

 of their constitution — valuable then as now, for the employ- 

 ments to which they could be put, the producer prudently 

 regarding their constitution with a wise indifference. Hence, 

 then, we are on sure ground in adopting action as a first prin- 

 ciple, whether we should have, or not have, to accept " being " 

 or " constitution " at a later period. 



(6) Chemical action, however, is not indeterminate. If it 

 were so, all possible reactions might occur at one time, and all 

 reactions would be possible. Isomerism could no longer arise. 

 The two mononitrotoluols, for example, that are formed during 

 the nitration of toluol could possibly be converted into each 

 other, and would yield a confused or mean nitrotoluol ; nay, 

 rather, any nitric solution of toluol would be as definite a che- 

 mical substance as we now consider nitrotoluol itself. Thus 

 the old theological guess, Deus est actus purus, cannot be trans- 

 cribed for chemistry ; in this science, action is determinate, 

 conditioned, and a process. 



The most important character of chemical action is con- 

 tinuity, which, as has been already stated, is an immediate de- 

 rivative of the idea of "notion. When two or more substances 



