On the Prussic and Prussous Acids, 



107 



filled with distilled water; a disengagement of sulphuretted 

 hydrogen, of ammonia, and of caloric immediately took 

 place. The materials were boiled slowly together for three 

 hours, occasionally replacing the water which evaporated. 

 The whole was thm thrown on a filter; what remained on 

 the filter was black, and consisted of sulphuret of iron and 

 un decomposed prussiate of iron. The liquid that passed 

 through, I found on trial to consist of triple prussiate of 

 potash, and hydroguretted sulphuret of potash. In order to 

 complete the decomposition of the latter, I boiled the liquid 

 again, for the same time as before, with another half ounce 

 of prussian blue, and when cold filtered it. The filtered 

 liquid (A) was now nearly colourless, and free from hydro- 

 guretted sulphuret. On pouring a little of it into a solu- 

 tion of oxy-sulphate of iron, I was very much surprised to 

 find that" solution changed to a deep blood-red colour, 

 without any precipitate ensuing, instead of forming with 

 i£ a precipitate of blue prussiate of iron. So unex- 

 pected a phenomenon determined me to undertake an ex- 

 amination of this liquid ; with this view I subjected it to 

 the action of the chemical agents mentioned in the follow- 

 ing table. 



Table I. with Liquid A. 



Chemical Agents. 



Paper stained withl 

 turmeric J 



Paper stained with "1 

 litmus j 



Potash , 



Lime , 



Diluted sulphuric acid 



Nitric acid (pure) . . . 



Oxy-muriatic acid . . . 

 Muriatic acid (pure) . 



Muriate Parvus 



Tincture or" galls 



Nitro-muriate platina 



Effects. 



No change of colour. 



Do. 



Do, 



{No disengagement of ammonia, 

 nor anv apparent change. 

 Do. ' Do. 



{An expulsion of sulphurous acid; 

 the liquid becomes' slightly 

 opalescent. 

 {The acid assumes a red colour, but 

 this effect is not permanent. 

 This acid loses its smell. 

 No change. 

 A while precipitate. 

 No change. 



{A heavy brilliant ochre, yellow 

 precipitate. 

 N 3 Muriate 



