1816.}] New Compound of Phosphorus and Potash. 281 
8. The liquid of paragraph 4, which was exposed to the air, be- 
came, after some days, covered with a yellowish pellicle, of an oily 
appearance, which disappeared after some weeks. When this sub- 
stance was separated from the liquid, it assumed the appearance of 
No. 5. ; 
9. The two liquids (Nos. 4 and 5), being evaporated to the con- 
sistence of a syrup, yielded confused, and not permanent, crystals. 
Evaporated to dryness, they gave the phosphuret of potash under 
the appearance of a white opake mass, which, when strongly heated, 
burnt with a yellow flame. The residue of this combustion was a 
grey mass, semi-liquid, and deliquescent, and in its inside partly 
yellowish, partly blackish. 
* 10. The scales remaining on the filter are a true phosphuret of 
potash, and do not differ from the liquids 4 and 5, but by the differ- 
ence of the solid and liquid state. ‘hey deliquesce when left ex- 
posed to the air; and, when heated till they become dry, they take 
fire, and burn with a white flame. " 
11. The red matter of No. 6 becomes darker coloured when left 
exposed to the air, but it remains humid and coherent. When , 
treated with perchlorate (hyper-oxymuriate) of potash, it gives 
phosphorous acid gas, carbonic acid gas, and carbonate of potash. 
From an attentive examination of all these facts, it appears that 
they are the result of a play of affinities, in consequence of which 
the greater part of the phosphorus combines with the potash. The 
compound divides itself into two portions, one of which precipitates 
under the form of scales, and the other remains in solution. The 
solution of the phosphuret of potash (No. 4) contains, likewise, a 
certain quantity of alcohol of phosphorus; and the yellowish pellicle 
with which the liquid becomes covered, when left exposed to the 
air, is owing to this, that the alcohol, on evaporating, leaves the 
phosphorus in a state of extreme division, which enables it gradually 
to disappear when left in contact of air. 
Besides the principal compound, the phosphuret of potash formed 
in this process, others are likewise produced. © The alcohol is de- 
composed, its hydrogen is developed in the state of gas, and dissolves 
at the same time a portion of the phosphorus. The carbon of the 
alcohol combines with the phosphorus and potash, which produces 
the reddish-brown matter of No. 6, which is a triple compound of 
phosphorus, potash, and charcoal, as appears from the products 
~ when it is treated with perchlorate of potash, No. 11. 
The two solutions, Nos. 4.and 5, when burnt as described in 
No. 9, contain likewise a portion of oxide of phosphorus, from 
which proceeds the vétlowticy: and blackish colours which alternate 
in the residue of this combustion. 
I proceed to the action of the acids on the solutions of the phos- 
phuret of potash of Nos. 4 and 5. 
Hitherto the action of three acids only, the sulphuric, muriatic, 
and nitric, has been tried. They only produce an imperfect decom- 
position of the ph haret of potash. Sulphuric acid deprives the 
Vor, VII. N iv. T 
