82 Essays en Chemical Vhilosophy. 



I. Attraction. 



Attraction, in common language, is applied both to the cause, 

 a!id to the effect which that cause produces ; and though philo- 

 sopliers now use it in a more abstract and arbitrary manner, yet 

 tlicy appear to have chosen it in the first instance, rather as de- 

 scriptive of effects, than as expressive of" any abstract idea they 

 could form or convey of its essence. In this sense Newton con- 

 fjidcrcfl the word; and though he adopted and applied it, from 

 the Avant of a more suital)le word, in the most enlarged manner, 

 he complained of those who mistook his reasons for this, and 

 evidently considered attraction as only the effect of another 

 power*. The term ailraciion, as well as the term repulsion, can 

 express only the inere property of a power, and is therefore an 

 improper name for the power itself; and philosophers would 

 reiidcr an important service to science, were they imanimously 

 to cojisent to ititroduce for the latter some other word more de- 

 lined and correc': in its application, as the vis jiatJircc, or cause 

 jModucing attraction and repulsion, or attractive and repulsive 

 or other effef.ts. The reasons for this will appear to more ad- 

 va7iiage by and by. Let it suffice at present, to state, to define 

 and restrict the term, that the reader may understand the sense 

 invariably meant to attach to it in the remarks which may be 

 laid before him in these Essays. The vis nalurce is employed 

 as a term to express the sole grand power or principle of Nature; 

 and, agreeably to tiiis view, is defined to he that " cause which 

 produces all the wotion and unimi of mailer .'^ 



This general definition is offered, from a conviction that this 

 poiver is alone siifP.cicnt to explain all the pheenomena of Nature 

 and of Art. Let it not be imagined, that it is intended to ex- 

 press or to determine the nature or essence, or even all the pro- 

 perties, of such a ])ower ; or, that this power consists of one eler 

 meat alone ; for it is much more probable that its constituents 

 may form the basis of all matter : it is not however intended 

 that its compountl nature shall be contended for or maintained. 

 Tacts alone are tlic only sure foundation on which the philo- 

 sopher should altemjjt to establish his theory. Let the phseno- 

 mena of facts be otat^id correctly, and their number. Can it be 

 doubted, that with due attention they will be found to arrange 

 tljcmseh es undi r ot!C general principle, regulated by the same 

 laws, modified by circumstances? — Such a genfralization of na- 

 ture can alone, in my opinion, furnish a true theory. An artist 

 copies the forms, colours, and diversified appearances of nature— 



* See Attraction, Johnson's larpe Dictionary, and last page of Petnber- 

 tort's \'iew of Sa- Isaac Nc^Mon's Philosophy. 



the 



