48 Mr. Davy’s Experiments on 
In all trials of this kind, hydrogene was produced ; and in 
some of them there was a loss of nitrogene. This at first 
seemed to lead to the inference that nitrogene is decom- 
pounded in the process ; but I found that, in proportion as the 
potassium was introduced more free from a crust of potash, 
which would furnish water and consequently hydrogene in the 
experiment, so in proportion was there less of this gas evolved ; 
and in a case in which the greatest precautions were taken, the 
quantity did not equal | of the volume of gas, and there was 
no sensible quantity of nitrogene lost. 
The largest proportion of nitrogene which disappeared in 
any experiment, was ~ of the quantity used ; but in this 
case the crust of potash was considerable, and a volume of 
hydrogene, nearly equal to £ of the nitrogene, was produced. 
It cannot be said, that the nitrogene is not decomposed in this 
operation ; but it seems much more likely that the slight loss 
is owing to its combination with nascent hydrogene, and 
its being separated with the potassium in the form of the 
gray pyrophoric sublimate, which I have found is always pro- 
duced, when potassium is electrized and converted into vapour 
in ammonia. 
The phosphuret of lime in its common state, is a conductor 
of electricity ; and when it was made the medium of commu- 
nication between the wires of the great battery, it burnt with 
a most intense light. It was ignited to whiteness in nitrogene 
gas ; a little phosphuretted hydrogene was given off from it, 
but the nitrogene was not altered ; the apparatus was similar 
to that used for the potassium. 
As almost all compounds known to contain hydrogene, are 
readily decomposed by oxymuriatic acid gas, a mixture was 
