ON THE SIGNIFICATION OF CHEMICAL TERMS. 87 



H'hat additional force can be gained from an additional 

 quantity of potassia, which must be without the sphere, of 

 action?'* This is a very proper statement of the question. 

 I wish the author had kejjt, closely to it, and not substituted 

 lor it anotiier and more complex one. Mr. M. continues; 

 *' tins objection however may be obviated, by considering 

 the mj\nner in wliich quantity operates.. Suppose two bo- 

 di^i(\4^ and B, to be presented to each other, the particles 

 of each within the requisite distance will combine together 

 in that proportion, in which they will be. mutually saturated. 

 Suppose it to be the one which is in Jarger proportion ; its 

 mass will continue to operate, aud, even if there be no suc- 

 cessive application of it to J5, froin the motion attending 

 the combination, its uncombined or unsaturated particles 

 will take part of, the particles of B which have entered into 

 the. combipation; so that the whole particle:^ of B which 

 have been attracted by A, instead of remaining combined 

 with part of it, in the })roportion in which saturation takes. 

 })laCV5 ,wiJl be diffused through the ma?5 ; and hence by an 

 increase in this mass there will be an addition to the force 

 .of affinity." Mr. M. then adds, "no law with regard to 

 chemical affinity is more important than Ihat now illus- 

 trated." But the illustration is almost lost upon me, for 

 want of .knowing the precise me«iniug of particle. 



Another of Berthollet*s observations is, ** that the action and on that of 

 of a substance, which tends to decompose a combination, ^^^'^ ^''^'!^'^^^^ °* 

 diii^inistiea ip j)ropor^ioq,9s/tt8 saturiitioa advanc^^ for this 

 substance lix^y in such case be considered as composed of 

 two [)arts, otiC of which is saturated, and tlie other free. 

 The former may be considered as inert, and as unconnected 

 with the latter, the quantity of which diminishes accojding 

 as the saturatiou advances; while on the contrary the action 

 of that which has been eliminated increases in {)roportion to 

 the augmentation ot its quantity, until .the equilibrium of 

 the eontendifig forces ends the operation, and hmit^ the 

 effect." Researches, page 1.5. I apprehend it is to this 

 that Mr. Murray- alludes, page 8-2, when he deduces the 

 law^ ".thjit the force of attraction is in the inverse ratio of 

 Baturation, or that the particles which enter first into com- 

 binatiou arc retained by u stronger affinity than those after- 

 ward 



saturation. 



