508 On the Analysis of the 
the two volumes of hydrogen existing ia 1 
volume of olefiant gas. 'The results of this 
experiment, therefore, confirm the analysis 
both of nitrous gas and olefiant gas by other 
methods ; for the former gas must consist of 
equal volumes of nitrogen and oxygen gases 
not condensed in bulk; and 1 volume of ole- 
fiant gas must be constituted of 2 volumes 
of hydrogen + carbon sufficient for forming 
2 volumes of carbonic acid. 
2.—Of the Analysis of Nitric Acid. 
THE evidence of the composition of nitric 
acid, on which the view, now most commonly 
taken of its constitution, is founded, is de- 
rived almost entirely from synthetic experi- 
ments. Sir H. Davy long ago stated(d) that 
4 in volume of nitrous gas and 2 of oxygen 
gas, condensed in water, absorb 1 in volume 
of oxygen to become nitric acid. But 4 in 
volume of nitrous gas being equivalent to 2 
of nitrogen and 2 of oxygen, the whole oxy- 
gen in nitric acid will be 5 volumes to 2 of 
nitrogen, or 2.5 volumes to one volume. 
The smallest proportion of nitrous gas, found 
(d) Elements of Chem. Phil. p, 264. 
