NATURE OF THE BLEACHING COMPOUNDS OF CHLORINE. 287 
This cloud is sometimes deposited in oily drops, which have all the pro- 
perties of chloride of azote; it is however more frequently carried off 
in the state of vapour by the gas which continues to be disengaged. 
This chloride of azote is very easily produced, especially when there 
is suspended in dilute chlorous acid a fragment of an ammoniacal salt, 
as for example of sulphate, phosphate, &c. The decomposition then 
goes on very slowly, but a small quantity of gas is absorbed, which is 
in this case a mixture of chlorine and azote, and not of pure azote, and 
there is formed at the same time a notable quantity of chloride of azote. 
This process appears to me the most convenient that can be employed 
for the preparation of this substanee. A very small quantity of it how- 
ever is obtained, if, instead of placing the fragment of salt in chlorous 
acid, it is mixed with the acid after being dissolved in water. The ac- 
tion then occurring instantaneously and rapidly on the whole mass, and 
no chloride of azote is obtained; or at any rate, if this compound is 
formed, it is carried off by the brisk effervescence which occurs in this 
case. 
It is almost useless to say, that no chloride of azote is obtained when 
concentrated chlorous acid is poured into concentrated ammonia. The 
action is then very rapid; it is accompanied with so great a disengage- 
ment of chlorine and so abundant an emission of gas, that it takes place 
with a sort of detonation. 
This action is still more vivid when bubbles of ammoniacal gas are 
added to a few drops of chlorous acid in a receiver over mercury. There 
is not only a great disengagement of heat, but an emission of yellow 
light, and the upper part of the receiver contains a mixture of azote 
and chlorine gas. 
It will be readily perceived that in all these circumstances it is prin- 
cipally by the oxygen of chlorous acid that the decomposition of the 
ammonia is effected, and that the chlorine and azote, simultaneously set 
free, sometimes coalesce to form chloride of azote, and are at others 
disengaged-in a state of aériform existence, according to circumstances. 
The two elements of the compound combustible are, on the contrary, 
completely burnt, in great measure by the oxygen when chlorous acid 
_is made to act upon gaseous hydrogenated combinations of phosphorus, 
arsenic, and of sulphur. Phosphuretted hydrogen, introduced into a 
small receiver containing a few drops of chlorous acid, burns on coming 
into contact with this liquid. There are produced phosphoric acid and 
chloride of phosphorus, which are ultimately decomposed into hydro- 
chloric and phosphoric acid. No uncombined phosphorus is observed, 
but pure chlorine is collected in the upper part of the bottle. 
The same phznomena occur with arseniuretted hydrogen. The 
combustion takes place with a flame of a blue tint. In the place of 
chlorous acid are found arsenic and hydrochloric acids, and the upper 
