of Chemical Philosophy and Nomenclature. 187 



ous, the latter in ic. As for instance the chlorureplatinoso- 

 potassique of Berzelius, is a compound of chloro platinous acid, 

 and the chlorobase of potassium, and is the chloro-platinite 

 of potassium. The chlorureplatinico-potassique of the same 

 author, is the chloroplatinate of potassium*. 



By analogy the intelligent reader may easily make these 

 examples a clue to designate any other of the double salts of 

 Berzelius so as to accord with the plan in question. He may 

 have a bromoplatinate or bromoplatinite, a iodoplatinate or 

 iodoplatinite, a fluoplatinate, fyc; or changing the radical a 

 chloroaurate or chloroaurite, a bromoaurate or bromoaurite, tyc. 



The terms amphigen and halogen being employed both 

 from expediency, and in honour of their author, we may use 

 his terms haloid and amphide, to distinguish the acids or bases 

 severally formed by these classes, the abbreviations halo and 

 amph, being employed in composition. Thus I designate the 

 acids formed by the halogen bodies with hydrogen, as halo- 

 hydric acids; those formed with that radical by the amphigen 

 bodies, as amphydric acids. As the same radical will in 

 other cases be found to form acids with several of the halogen 

 bodies, platinum for instance, the acids thus produced may 

 be called haloplatinic acids; or if gold were the radical, they 

 would be called haloauric acids. These examples will sug- 

 gest to the chemical reader a series of names, as for instance 

 haloargentic, halocupric, halostannic, halopalladic. 



I consider prussian blue as a cyanoferrite of the cyanobase 

 of iron, or briefly a cyanoferrite of iron. The diversity of 

 properties which enables two cyanides of iron to exist in com- 

 bination in this cyanoferrite, one as an acid, the other as a 

 base, is one among many other instances in which compounds 

 constituted of the same elements in the same ratio, have dif- 

 ferent properties, and are said in consequence to be isomeric, 

 or to afford cases of isomerism. 



The salt designated by Berzelius as the " cyanure ferroso- 

 polassiq?ie," is the well-known test for iron heretofore called 

 ferroprussiate of potassa; under the idea that it consisted of 



* In designating salts of the metals proper, as for instance, the nitrate of 

 mercury; the idea of the oxydizement of the metal is always understood, 

 although usually not expressed. In the instance above cited, we actually 

 mean the nitrate of the oxide, or oxybase of mercury. By analogy, I here 

 use the term chloroplatinate of potassium, for chloroplatinate of the chloro- 

 base of potassium. It is in fact well known to chemists, that acids do not 

 unite directly with metals. The only alleged exception to this rule, of 

 which I have any knowledge, is that of tellurium and sulphuric acid. It is in- 

 ferred, therefore, that when an acid is combined with a metal, the latter 

 must exist in the state of a base formed with the basacigen body which 

 enters into the composition of the acid. 



2 B2 



