4^6 Dr. Wall on the Phenomena 



defervedly occupied no finall (hare of the atten- 

 tion of philofophers ; becaufe on the knowledge 

 of thefe principles, depend, not merely a curious 

 fcience, but very many of the neccflary arts of 

 life. In the earlieft periods of philofophy, little 

 progrefs was made in this invedigation. Some 

 crude conjectures were advanced concerning 

 peculiar emanations, &c. which, having no foun- 

 dation in experiment, were as quickly reje<5led 

 as they had been formed. The patrons of the 

 corpufcular philofophy imputed the influence 

 of bodies on each other, or the defedl of fuch 

 influence, to the peculiar forms of their original 

 particles ; and the mechanic fe£t fuperadded to 

 this fyfl:em the dodrine of attraftion. The 

 theory which depends upon the form of the 

 conftituent particles of bodies, is very weak 

 and unfatisfa(flory, and, if it has not been ab- 

 folutely confuted by experiments, has certainly 

 received no confirmation from them. But the 

 grand principle of attraction, has, by the cleared 

 evidence of conclufive facts, received the mod 

 ample confirmation, its laws have been ex- 

 plained, and the univerfal extent of its operation 

 has been fo fully demonflrated, that Bergman 

 was perfectly juflificd in fpeaking of it, as the 

 principal agent in every operation, grand or 

 minute, in the fyftem of the world, " cui omnia 

 in glob? noftro obedire videntur." 



The 



