S/6 St+ On the Analysis of the 
be necessary for perfect decomposition, in 
order to prevent the formation of uitrous acid 
vapour, which is always generated when the 
nitrous oxide is in exeess. For example, 
10 measures of ammonia were deflagrated 
with 12 or 13 of nitrous oxide, the full pro- 
portion of the latter being, if pure, 15 mea- 
sures. All the oxygen of the nitrous oxide 
was transferred to the bydrogen of the am- 
monia, water was formed, and the whole 
nitrogen of both gases remained as the aéri- 
form preduct, mixed with a small quantity 
of hydrogen gas, for the combustion of which 
the nitrous oxide had not supplied sufficient 
oxygen. This quantity of hydrogen being 
too small to forma combustible mixture, it was 
necessary to make an addition of that gas, and 
toemploy, for the second combustion, more 
oxygen than was requisite to saturate the 
hydrogen added. The quantity of hydrogen, 
originally in the mixture, was thus easily 
determined, and, when added to the volume j 
of pure nitrous oxide expended, the sum 
expressed the whole hydrogen of the alkali. 
In this more summary method of analysis, 
results were obtained, which fully confirmed 
those established by electrical agency, all 
concurring to prove that ammonia affords, by 
decomposition, a quantity of nitrogen and hy- 
