On Chemical JVomendaiure. ' 263 



to me respecting the nomenclature which I have employed in my 

 Treatise of Chemistry. 



I perceive that having contemplated chemical phenomena under 

 different points of view, we differ as to the nomenclature which is 

 the most appropriate for their description. I consider the combina- 

 tions of metals with chlorine, bromine, he, as salts ; whilst you, in 

 accordance with Mr. De Bondsdorff, consider them as bases and 

 acids, capable of forming salts by their union. 



If it vi^ere expedient that chemical classification should be depen- 

 dent on the number of simple bodies which enter inio each combi- 

 nation, this idea of Mr. De Bondsdorff would without doubt be pref- 

 erable ; but if attention be due to the chemical properties which 

 characterize combinations, we cannot adhere to an arrangement foun- 

 ded on the number of the elements. Yet so essential is it in chem- 

 istry to have reference to properties, that a system of chemistry in 

 which common and analogous properties should not affect the ar- 

 rangement, would present a mass of facts so chaotic, that no memory 

 would be competent to retain them. In a system thus strictly con- 

 formable to the ideas of Mr. De Bondsdorff, cyanogen, though in 

 its properties resembling chlorine or bromine, which are simple bod- 

 ies, ought to be considered, also, as a base or as an acid, having 

 azote for its radical — I am persuaded you would not approve of ex- 

 tending the system of De Bondsdorff so far; but if it be correct, it 

 would be inconsistent not to make this extension. 



But let us return to the combinations of the metals with chlorine, 

 fluorine, he, and make, in imagination, the following experiment. 

 Let us take two portions of caustic potash, a base in which the basic 

 characters are more striking than in any other. To one, let us add a 

 sufficiency of sulphuric acid to extinguish entirely its basic property ; 

 we shall then have a neutral body of a saline taste. You will admit it 

 to be a salt. Now let us add to the other portion, hydrofluoric acid. 

 At a certain point the basic properties of the potash will disappear, 

 and we shall have a resulting compound quite as neutral as the sul- 

 phate of potash, endowed with a saline taste entirely analogous to that 

 of the sulphate. The basic properties of the potash are destroyed by 

 the hydrofluoric acid, as well as by the sulphuric acid. But you will 

 allege the resulting combination is not a salt, but a base which has ex- 

 changed one basifier (oxygen) for another basifier (fluorine.) In proof 

 you may add as much more hydrofluoric acid, which combining with 

 the new base will form with it a crystallized salt. But this salt is not 



