CHAPTER II. OF CHEMISTRY. SECTION I. 765. CHEMISTRY is that physical science which comprehends the actions, passions, and effects of all material substances. 766. Now, we have seen that all physical effects are subtended by, and must be the results of, an original physical agent and patient, or of the relatively flowing and fixed; and material substance can be known only in effect: while three primary states, or modifications of matter, are admitted, and no more; namely, the solid or fixed, or that state of substances in which their parts cohere and resist change; the liquid, or that state in which their parts equilibrate, change place reciprocally, or flow; and the elastic, or that state of substances in which their parts change place, impel, and repel each other, and are permanently fluid: states that are not absolute, but relative. 767. The ultimate elements of chemic matter are, therefore, the universal physical agent and patient producing effects under the solid, liquid, and elastic forms or states, and into these the elements of both antients and moderns may be resolved. 768. Thus, according to the most antient physics, the elements of matter are four, three fluid and one fixed, — Fire, Air, Water, and Earth, which have been regarded by modern writers in a literal sense, as denoting four distinct, simple, primary material substances, and as concurring principles, recognised by the antients in the production or composition of all material bodies; till, by the experimental analysis of these substantial elements, later chemists have resolved them into an indefinite and varying number of radical principles, undecompounded substances, or elements of matter. 769. If, nevertheless, the antients originally intended to denote by these four terms, not the matter, but the elementary modes or forms of material substances, preference is due, theoretically, to the permanent simplicity of this antient doctrine, however justly, in a practical view, the labours and discoveries of modern chemists may be valued and admired. 770. To the latter of these it yet remains to decompose, or resolve elementarily, the fifty-four substances at present regarded by them as simple and elementary; and, as upwards of forty of these are metallic, the analysis of one metallic base will probably lead to the reduction of the whole, the primary oxygenous and hydrogenous elements excepted, and establish the true induction of the elements.* 771. We have assumed, therefore, that the true elements of chemic nature are an agent producing the solid, liquid, and elastic forms, or states, of matter, by the concurrence of a patient or reagent; elementary states, antiently denominated after those natural substances in which they are most palpable and apparent, as Action in Fire, Elasticity in Air, Liquidity in Water, and Solidity in Earth, the last, and most passive or inert state, * It appears, therefore, to be the great problem of modern chemistry at present to decompose the simple flagrant or inflammable bodies, including the metals; when all the modern simple substances will be resolved into the sole pure conflagrant substance or supporter of fire, oxygen, and the sole pure flagrant substance, hydrogen, which two are synonymous or identical with the active and passive elements of all matter; and thereby the theory of Chemistry will be consummated, and a firm basis established for all physics. Toward these there appears to be a strong tendency in the present investigations of Natural Philosophers; and the facts and opinions advanced in the recent ingenious and valuable work of our friend John Howard Kyan, Esq., so well known to the public by his eminence in practical chemistry, "On the Identity of the Elements of Light and Matter," are remarkable confirmations of this doctrine. |