Compounds of Nitrogen. 517 
drogen gases equivalent to twice its volume, 
and consisting of 1 volumeof nitrogen and 3 of 
hydrogen. ‘To preserve, however, an agree- 
ment between thetheory of volumesand that of 
atoms, it is necesSary rather to view ammonia 
as constituted of 2 volumes of nitrogen and six 
of hydrogen. For since 2 volumes of hydrogen 
unite with one of oxygen to form water, 
every ultimate volume of hydrogen, (on the 
supposition that water is constituted of an 
atom of each of its elements) must, like the 
ultimate volume of nitrogen, be double that 
of oxygen. ‘Two appreciable volumes of 
nitrogen, and two of hydrogen, will contain 
then the same number of ultimate particles 
or atoms, and multiples of 2 in volume of 
either gas, will be multiples of the numbers 
of single atoms of hydrogen or nitrogen. I 
must be acknowledged to be remarkable that 
the only known compound of nitrogen and 
hydrogen should, according to this view, be 
constituted of one atom of the former ele- 
ment and three of the latter; and that, du- 
ring the decomposition of ammonia by elec- 
tricity, those elements, disunited from each 
other, should not recombine in new propor- 
tions, as happens to the elements constituting 
the aériform compounds of nitrogen and 
oxygen, when subjected to the same decom- 
posing influence, 
