ON POTASSIUM, SODIUM, AND OXIMURIATIC AClD. l3l 



of chemical union with the acid, &c. But, whichever be 

 the case, it is true, "that the process cannot be used to 

 expel the last portion of water from the alkali'% when the 

 object is to obtain a ponderable mass of alkali free from 

 water. 



When fused potash is exposed to a red heat in an open Potash ex- 

 vessel, white fumes are observed to play over it; these, no f^^^^ open^* 

 doubt, are the particles or small drops of the condensed ve=!se!, and in 

 liquid hydrate, similar to the visible mist or condensed ^ S^n^arrc . 

 steam over hot water. From this and the above observa- 

 tion, then, it is probable, that in the gUn barrel experiment, 

 not only particles or atoms of hydrate of potash, but also of 

 potash, and of steam, may come into contact with the red- 

 hot iron; hence may be explained the production of hydru- 

 ret of potash or potassium, of oxide of iron, of hidro^en, Alloy of pot- 

 and of the wliite amalgam or alloy of potash and iron. This ash and iroa. 

 last is easily exhibited by keeping carbonate of potash in 

 fusion for some time in an iron spoon by an intense heat ; 

 after the potash is washed oif, the whole surface of the 

 spoon, which has been in contact with the fused carbonate, 

 is white as if tinned, and may be acted upon by an acid 

 without losing its colour*. 



As for the complex nature of the decomposition of by- Complex na- 



drate of potash, I see no «rreat reason to wonder at it. The *"'"® of the de* 

 ' ^ -11 composition of 



article consists of 3 elementary prmciples ; so does wood, hydrate of pot- 

 Why, it may with equal propriety be asked, does wood, in ^^^• 

 its decomposition by heat, exhibit such a mixture of 

 principles? Charcoal, water, carbonic acid, carbonic ox- 

 ide, cafburetted hidrogen, and hidrogen, are among the 

 products of the destructive distillation of wood. 



I was surprised at your correspondent's observations on Levity of po- 

 the argument I have drawn for potassium being a compound tassium. 

 of hidrogen from its levity. I venture to say, that Mr. 

 Davy will allow the argument to have some force. In the 

 place referred to, Mr. Davy does not say a word about the 

 notion, that hidrogen united to potash ought to make a com- 

 pound specifically lighter than potash. His answer, which 

 is pertinent and to the purpose, is to those who object to 

 potassium and sodium being classed amongst the metals^ 



• • On pola^satcd iron see also Journnl, Vol, XXV, p. 51. 



K 2 Bierely 



