hlSTORY OF PRUSSIATES; ^05 



Dissolved and crystallized, it affords yellowish Crystals, of 

 a sweetish taste, and furnishing prussic acid and white 

 prussiate, when acted upon by muriatic acid. This is the 

 prussiate freed from oxide proposed by Mr. Richter. 



The alcoholic solution being distilled almost to dryness, 

 and the residuum covered with alcohol at 30°, one portion 

 is dissolved, and another falls to the bottom. The preci- 

 pitate is found, on examination, to be carbonate of potash, 

 with a remnant of the triple prussiate. The new solution 

 being distilled affords simple prussiate, which is discover- 

 able by its taste, and by its property of not producing blue 

 with solutions of red oxide. These are the products I have 

 found after subjecting the triple prussiate of potash to 

 fusion. 



Consequeiices. 

 . The triple prussiate cannot support a considerable iem- Recapitulation 

 perature without being simplified in its composition. It° 

 Trees itself from black oxide, and passes to the state of 

 simple prussiate: but this too is reducible to something 

 more simple, as we shall see below ; and it then leaves in 

 its stead potash and the usual results of the prussic acid, 

 ammonia, and carbon. A portion of the latter serves to 

 disoxigenize the black oxide, reducing it to iron, and form- 

 ing carbonic acid with its oxigen. 



During these changes, a part of the triple and simple 

 prussiates escape being acted upon, in proportion no doubt 

 as they become enveloped in the carbonate : but it is to be 

 presumed, that a high and continued heat, in vessels capa- 

 ble of supporting it, would ultimately reduce these prus- 

 siates to two binary combinations, which are ammonia and 

 carbonic acid, potash, iron, and some remains of carbon, 

 that the oxigen of the iron and the water were incapable of 

 acidifying. 



Simple prussiate of "Potash* 



This is obtained by saturating potash, in Scheele's mode, Mcde of ob 

 with prussic acid disengaged from the prussiate of potash s YmnleVmssiate 

 or of mercury. But a more expeditious way is keeping of potash. 

 alcohol on a concentrated lixivium of animal coal, shaking 



Vou XVIL— July, 1807. I it 



