,%.jf> SEttEaiCAL TABLE OF ELECTIVE JIT TRACT tO*S. 



be supposed to be tolerable approximations to such mea- 

 sures; at least if any two of them are nearly in the tna« 

 proportion, it is probable, that the rest cannot deviate very- 

 far from it: thus, if the attractive force of the phosphoric 

 acid for potash is about eight tenths of that of the sulfuric 

 acid for barita, that of the phosphoric acid for barita must 

 be about wine tenths as great ; but they are calculated only 

 to agree with a certain number of phenomena, and will 

 probably require many alterations, as well as additions, 

 when all other similar phenomena shall have been accurately 

 investigated. 

 The facts may There is, however, amethod of representing the facts, which 

 r^^ e ^ nted - have served as the bases of the determination, independently 

 kf jra&eus. of any hypothesis, and without being liable to the contingent 

 necessity of any future alteration, in order to make room for 

 the introduction of the affections of other substances ; and this 

 method enables us also to compare, upon general principles, 

 amalti tilde of scattered phenomena, and to reject many which 

 have been mentioned as probable, though doubtful, with the 

 omission of a very few only, which have been stated as ascer- 

 tained. This arrangement simply depends on the supposition, 

 that the attractive force, which tends to unite any two sub. 

 stances, may always be represented by a certain constant 

 quantity. 

 There most he From this principle it may he inferred, in the first place, 

 tbe^^teat *^ a * tn€re k* 118 * De a sequence in the simple elective attrae- 

 tractions. tions. For example, there must be an errour in the common 



Enwurs in the ^ a ^] es c f e i ec tfre attractions, in which magnesia stands abovt 

 ~» tables. . 



ammonia wnder the sulfuric acid, and below it under the 



phosphoric, and the phosphoric acid stands above the sulfuric 

 under magnesia, and below it under ammonia : since such an 

 arrangement implies, that the order of the attractive forces is 

 this; phosphate of magnesia, sulfate of magnesia, suifateof 

 arf monia, phosphate of ammonia, and again phosphate of 

 magnesia; which forms a circle, and not a sequence. We 

 mast therefore either place magnesia above ammonia under 

 ihe phosphoric acid, or the phosphoric acid below the sulfu- 

 ric under magnesia; or we roust abandon the principle of a 

 Buiaerical representation io this particular case, • 



In 



