﻿328 Transactions — Chemistry. 



If the terms acidity and alkalinity have any meaning, or if the test here 

 applied to discover these properties is trustworthy, we cannot refrain from 

 classifying those substances specified in the first and second columns of the 

 foregoing table as alkaline and acidic respectively. 



That the test used is trustworthy, in the case of alkalinity at least, and 

 these results consequently so far correct, is in the highest degree probable, from 

 the fact that it has been approved of, and I may say recommended, for this 

 latter object, by one who attempts to demonstrate the condition of neutrality 

 in a case for which, as aforesaid, I have assigned alkalinity. 



The correctness of this table being allowed, we may safely and largely add 

 to it by filling in with those salts analagous in chemical composition to 

 the ones stated, or we may at once deduce from it the following general con- 

 clusions :— 



1. That those salts of the earthy oxides, as also those of the oxides of silver 

 and lead, which contain single equivalents of carbonic, phosphoric, arsenic, or 

 boracic acids, are alkaline. 



2. That the common silicates of these oxides are also alkaline. 



3. That the salts of the sesqui-oxides and the remaining metallic protoxides 

 are acid when containing one equivalent or more of phosphoric or arsenic acid. 



4. That the silicates of the sesqui-oxides are neutral. 



The salts of the oxides, therefore, enumerated under the foregoing Nos. 1 

 and 2 appear to agree, in respect to the characters under investigation, with the 

 corresponding salts of the alkalies ; the oxides themselves, as compared to those 

 of the so-called alkalies, thus exhibiting an equal alkalinity through all their 

 combinations, and therefore each oxide is, as far as we can judge, similar in 

 molecular arrangement throughoiit all such combinations. 



In the case of those salts comprised in section 3, it is seen that they compare 

 with the sulphates and chlorides of the same or corresponding bases in being 

 acid ; but the degree of this acidity is, we know, dissimilar, and may be 

 inferred from the character of alkaline salts with these acids respectively, 

 which has been already described. 



The facts above stated have a great significance in respect to the relative 

 potency of the alkalies as compared with that of the alkaline earths ; thus, the 

 perfect equality of the bases magnesia and lime as compared with potash 

 (equivalent for equivalent) in respect to alkalinity (here shown) will, if fully 

 recognised, oblige us to dispute the title which this base now holds — that 

 of being the most powerful of any we are yet conversant with. 



In reality lithia has far better claims upon this position, as having the 

 lowest combining number, and being, ecpiivalent for equivalent, undoubtedly 

 equal to potash in basicity, it has, therefore, for similar weights, the greatest 

 saturating power for acids. 



