CONSTITUTION OF SALTS. 151) 



that it appears more like a compound of that oxide of nitrogen 

 with oxygen, than a compound of nitrogen itself with oxygen. 

 When the peroxide of hydrogen was first discovered by Thenard, 

 he was led by the whole train of its properties to view it as a 

 compound of water and oxygen, into which it is resolved with 

 so much facility, and to name it accordingly oxygenated water, 

 which it may be, and not a direct combination of hydrogen and 

 oxygen ; or its formula may be HO -f O, and not HO 2 . The 

 periodide of potassium and the other analogous compounds 

 obtained by dissolving iodine in metallic iodides, were first 

 termed ioduretted iodides from similar considerations, and the 

 hyposulphites, obtained by dissolving sulphur in sulphites, 

 sulphuretted sulphites. It may be doubted whether chemists 

 would return with advantage to any of these expressions, the 

 views of composition which they indicate being uncertain, and 

 not offering a sufficient inducement to depart from the more 

 systematic designations. The peroxide of hydrogen, for instance, 

 may be easily resolved into water and oxygen, not because 

 water pre-exists in it, but because water is a compound of great 

 stability and is formed when peroxide of hydrogen is decom- 

 posed. Nitric acid, also, is as likely to be a compound of 

 peroxide of nitrogen with an additional atom of oxygen, as of 

 deutoxide of nitrogen, with three atoms of the same element. 



Certain compound bodies, however, have been observed to 

 act the part of a simple body in combination, and can be traced 

 through a series of compounds. The following substances, for 

 instance, may be represented with considerable probability as 

 compounds of carbonic oxide, as in the formulae : 



CO, carbonic oxide. 



CO + O, carbonic acid. 



CO + CL, chloroxicarbonic acid. 

 2 CO + O, oxalic acid. 

 2CO + C1, chloroxalic acid. 



Carbonic oxide is said to be the radical of this series, a name 

 applied to any compound which is capable of combining with 

 simple bodies, as carbonic oxide appears to do with oxygen and 

 chlorine in these compounds. Messrs. Liebig and Wohler have 

 shewn by decisive experiments that such a radical exists in the 

 benzoic combinations, which may be represented thus : 

 C 14 H 5 O 2 + O, benzoic acid. 

 C u H 5 O 2 -f H, essential oil of almonds 

 C 14 H 5 O 2 4-C1, chloride of benzoyle, etc. 



