146 Anal If ses of Books. [[Aui. 



It is only in the subsalts of acids containing an odd number of 

 atoms of oxygen, that exceptions to the law can exist. It is to 

 them, therefore, that we must have recourse when we wish to 

 ^determine whether this empyrical law of Berzelius be founded 

 in nature or not. Now, there are thirteen acids, the integrant 

 particles of which contain an odd number of atoms of oxygen. 

 The following table exhibits the names of these acids, together 

 with the nuniber of atoms of oxygen in each. 



Atoms of oxygen. 

 Acetic acid* t9>i...«. 3 

 Succinic. .^••^••.•. 3 



Atoms of oxygen. 



Sulphuric acid , . 3 



Arsenic *,.•..♦.* 3 



Chromic. ai,-\^/V*«lA<;ii ^;^' i 'i ^'' Benzoic 3 



Molybdic •.5V;)XaUy4 ; 3*^0 o q 

 Tungstic. »/L WVi U § f;<ii3xft' 



Nitric 5 



nsi- f3£frartaric 5 



Hyposulphuric 2^ 



"Now, although the number of subsalts which I have examined 

 is exceedingly small, because my object was not to investigate 

 the truth of Berzelius' law, but to determine the quantity of 

 water of crystallization which the salts contain, yet tnere occur 

 several which are inconsistent with Berzelius' law. This is the 

 case, for example, with the disulphate of alumina, the atoms of 

 oxygen in the base being 2, and those in the acid 3. The fol- 

 lowing subsaUs are precisely in the same predicament: 



,.ld6^1^m91 amoa iyo Waioq i Atoms of oxygen in b*se. 



Dmitrate of alurmna . . • •c.\»^fff^^4-f , .? 



,„ Trisnitrate of alumina . , '. • • ^♦.•LiH^. • 3 



-^, Diprotarseniate ot iron .... it^,.^*HK», 2 



V,om ^i^itrat^ ^^ ^ad ^--^/^•^iffJ•oL^. >-• 



-// d.n giacetate of lead .... . ,^,..,^5^^^^^2 ^^^ 



;,^v, , Binitrate of bismuth ,^a /?» ~.\Ai, 



These examples comprehend not only nitric acid, which Berze- 

 lius has recognised as an exception to his law ^ but likewise, 

 sulphuric acid, arsenic acid, and acetic acid. 



" It would certainly be a most remarkable circumstance if 

 2 atoms of any protoxide were incapable of combining with 1 

 atom of any of the 13 acids in the preceding list. I have given 

 seven examples of such combinations; and am persuaded that 

 many more will be discovered whenever the attention of chemists 

 is particularly turned to the subsalts. 



" There is another kind of saline combination in which ex- 

 ceptions to the law of Berzelius may also be looked for ; I mean 

 those salts which I have distinguished by the epithet sesquisalts 

 or snbsesquisalts. In the sesquisalts, 1t[ atom of acid unite with 



