56 Account of a numerical Table 



always decompose each other, unless each acid be united to 

 the base nearest to it: for example, sulfuric acid, barita, 

 potass, soda, amfnonia, strontia, magnesia, glycina, alumina, 

 zirconia, lime, phosphouic acid. The sulfate of potass de- 

 composes the phosphate of barita, because the diflerence of 

 the attractions of barita for the sulfuric and phosphoric 

 acids is greater than the difference of the similar attractions 

 of potass; and in the same manner the difference of the at- 

 tractions of potass is greater than that of the attractions of 

 soda ; consequently the difference of the attractions of barita 

 must be much greater than that of the attractions of soda, 

 and the sulfate of soda must decompose the phosphate of 

 barita: and in the same manner it may be shown, that each 

 base must preserve its relations of priority or posteriority to 

 ^ every other in the series. It is also obvious that, for similar 

 reasons, the acids may be arranged in a continued sequence 

 between the different bases; and when all the decomposi- 

 tions of a certain number of salts have been investigated, we 

 may form two corresponding tables, one of the sequences of 

 the bases with the acids, and another of those of the acids 

 with the diflerent bases; and if either or both of the tables 

 are imperlcct, their deficiencies may often be supplied, and 

 their errors corrected, by a repeated comparison with each 

 other. 



In forming tables of this kind from the cases collected by 

 Fourcroy, I have been obliged to reject some facts, which 

 were evidently contradictory to others, and these I have not 

 thought it necessary to mention : a few, which are positively 

 related, and which are only inconsistent with the principle 

 of numerical representation, I have mentioned in notes ; but 

 many others, which have been stated as merely probable, I 

 have omitted without any notice. In the table of simple 

 elective attractions, I have retained the usual order of the 

 diflcrent substances; inserting again in parentheses such of 

 them as require to be transposed, in order to avoid inconse- 

 quences in the simple attractions : I have attached to each 

 combination marked with an asterisc the number deduced 

 from the double decompositions, as expressive of its attrac- 

 tive force j and where the number is inconsistent with the 



corrected 



