84 ESSAYS AND OBSERVATIONS 



The larger the fubdance is which we in- 

 tend to move with a given velocity, the 

 greater force muft be applied : And, could 

 we fuppofe it a<5l:nally infinite, no finite 

 force could move it at all. 



TiiERF, is a very extraordinary palTage 

 ill Mr iM'Laurin's Account of Sir Ifaac 

 Ncwion's Philofophy, p. loo. which, in 

 refpeci: of the high merit of the author, 

 delerves our atceation. It is there faid^ 

 *' That, for aught we know, matter may 

 " be of kinds fo different from each other, 

 '* that the folid elementary particles of 

 " the one may have a greater inertia than 

 ** equal folid elementary particles ot the 

 " other kind." This conjedure, if true, 

 would efl^eclually overturn what hath been 

 now advanced. But it appears to be e- 

 qually inconfiftent with his own account 

 of iJiertia^ and occurs only in a pofthu- 

 nious work. The inertia of body is a 

 negative quality, or a negation of all po- 

 fitive power, and therefore can admit of 

 no degrees of a greater or lefs than 7^ gi- 

 ven quantity of matter. Two bodies, 

 or two elementary particles of equal quan- 

 tities 



