Existence of Compound Radicals in Amphide Salts. 63 



the salt being Cu.SO 4 , is simply resolved into its elements, but 

 SO 4 reacting on the water, produces H.SO 4 and O at the posi- 

 tive electrode. On the old view, it was supposed that water and 

 sulphate of copper were both decomposed, oxygen and acid being 

 evolved at one side, and oxide of copper and hydrogen being sep- 

 arated at the other; which reacting produced water and the 

 metal. Such an explanation, however, is directly opposed to the 

 law of the definite" action of electricity, and cannot be received. 



"In the case of solutions of chlorides or iodides, where there can 

 be no doubt of the relations of the elements, the results of voltaic 

 decomposition are precisely similar. Chloride of copper gives 

 simply chlorine and copper, no water being decomposed. Chlo- 

 ride of sodium or iodide of potassium give chlorine or iodine at 

 the one electrode, and alkali and hydrogen at the other ; the evo- 

 lution of these last being caused by the action of the metallic basis 

 on the water of the solution. 



" Professor Daniell, to whom these important electro-chemical 

 researches are due, considers the truth of the binary theory of 

 salts to be fully established by them. 



"If this theory be adopted, a profound change in our nomencla- 

 ture of salts will become necessary. Graham has proposed that 

 the name of the salt radical should be formed by prefixing to the 

 word oxygen the first word of the ordinary name of the class of 

 salts, and that the salts be termed by changing oxygen into oxides. 

 Thus SO 4 sulphatoxygen, gives sulphatoxides, the sulphates. 

 NO 6 nitratoxygen, gives nitratoxides, the nitrates, and so on; but 

 I consider that the form of nomenclature proposed by Daniell de- 

 serves the preference. It has been described (p. 314) that Fara- 

 day proposed to term the elements which pass to the electrodes 

 of the battery, ions ; acting on this, Daniell proposes to term the 

 electro-negative element of the sulphates oxysulphion, that of the 

 nitrates oxynitrion, and so on, and the salts may be termed oxy- 

 sulphion of copper, oxynitrion of sodium, &c. It would be de- 

 sirable, however, for a long time, to introduce these names only 

 where theoretical considerations rendered their employment de- 

 cidedly useful, and hence, in all future description of the salts, I 

 shall make use of the language of our ordinary views, and treat 

 of their preparation and composition without any reference to the 

 discussion in which we have been engaged. 



