412 LIFE OF D ALTON : 



somewhat dogmatically upon his two laws of Continuity and 

 Sufficient Season, rejected this notion of solid primitive 

 atoms; and arguing, as Descartes had done, that no body 

 can be admittad as indivisible, sought to supply their place 

 by an hypothesis of monads, or points without extension. The 

 more celebrated dynamic theory of Boscovich is a modifica- 

 tion of this view ; in which, for the action of material particles, 

 is substituted the idea of simple centres of force, that is, 

 points of attraction and repulsion. Though* this view has 

 gained some favour of late, we cannot find in it more than a 

 new mode of expressing the limit of our knowledge. And the 

 expression is faulty in itself, inasmuch as the term force can 

 only be intelligible where there is something which is the 

 subject of it; and attraction and repulsion are without 

 meaning, unless there is something more than unextended 

 points to be attracted or repelled. Boscovich vindicated his 

 doctrine with ingenuity ; but we doubt whether it has ren- 

 dered, or can ever render, any real aid towards the solution 

 of this great physical problem.- 



We now come with satisfaction to those more recent re- 

 searches, which, based on experiment, have given to this 

 subject all the higher characters of an exact science. We have 

 seen that the most complete of earlier systems scarcely went 

 beyond the fortuitous concourse of atoms as the cause of all 

 existing things. It is the pride of our time to have changed 

 chance into certainty; to have submitted to numerical 

 formulae the various relations of material bodies ; and to 

 have framed a system of definite proportions, perfect enough 

 to allow the prediction of the unknown from that which has 

 been already discovered. In fine, it has belonged to the 

 progress of this part of science (as, in truth, of every other) 

 to put aside all accident from the creation of what we see 

 around us ; and to give proof and certainty to those great 



