196 ON CHEMICAL ATTRACTION. 



" contact with the sulphuric acid ;" how then does it after- 

 Ward " df^termitie the, combination of the sulphuric acid 

 *' wjth the lime?" A power which is only evolved at the in- 

 stant of the combination of two suhstances, cannot surely 

 influence, or determine that corabinatjon. 



Cohesion is a power, which is exerted between integrant 

 particles only ; in this instance between the integrant parti- 

 cles- of snlphate of iime; it has no influence before their 

 existence, and consequently cannot contribute to their for- 

 mation, it cannot.therefore be a power in addition to those 

 wbich preexisted, so as in itsi; operation to determine the^ 

 combination of the snlphuric acid and the lime. 



It appears to me, therefore, that Bertlieilet has attributed 

 ; the formation of saline compounds to the active energy of a 



|)Ower, the very existence of which, according to his own 

 definition, must be coeval with, and cannot precede and in- 

 fluence their formation. 

 Cohesion be- - Now it is to be observed^ that the proposition, that cohe- 



r.veeti I e par- siou.in a compound is a force which determines the forma- 



tides of atom- . ' 



pound is a tion of that compound, is really a fact as well established as 



farce 4bat de- anyin chemktrv. For, " if all the decompositions ascribed 



tarmines its. '' "... , . . 



lormat'ion. *' to complex affinities be investigated, it will be found, that 



" the prevailing affinity has been always ascribed to those 



*' substances, which have the property of precipitating, and 



" of forming a salt, which can be separated by cry»tal- 



" lization*." The formation of these compounds, therefore, 



can scarcely be attributed toany other cause, than that which 



Berthollet alleges; namely, the operation of the attraction 



, of Go!,esiou in the compoancis formed. 



Combination '^" the contrary, that cohesion is exerted between com- 



ar.d aggrcgii- pound integrant particles only, nay, the very existence of 



effect ^o/hete- ^^^^ particles^ is eniiiely hypothetical. The former proposi- 



rcgeaeous and tion is supported by an ample namber of experiments; the 



aUracUoii^^"* latter, which is in contradiction to it, is merely matter of 



opinion. Experiment, which is the light of Nature, shows 



us, that that power, which we term the attraction of cohe- 



{|l ■ sion, does influence and determine the combination of those 



substances, or pi' those particles, which constitute a ccm- 



pouud with aiuch cohesion : but, as it has been shown, these 



., ; * fterilioliet, Researches, p. 106. 

 ;, . .• w particle* 



