296 BALARD'S RESEARCHES CONCERNING THE NATURE OF 
cubic inches, the absorption, which begins to take place very slowly, 
terminates with a detonation accompanied with disengagement of light, 
and there is then found in the upper part of the receiver a mixture of 
chlorine and oxygen. It is probable that the heat developed in this case 
by chemical action occasions the decomposition of the portion of gas 
which had not been absorbed. 
Silver leaf also acts upon chlorous acid after a certain time. The 
metal is partly converted into chloride, and oxygen is disengaged ; but 
the heat developed by this re-action also occasions the decomposition of 
a part of the gas, and chlorine is found mixed with oxygen. 
Chlorous acid gas is also decomposed by the greater part of the com- 
pound combustibles. Cyanogen and chlorous acid gas act but slowly 
upon each other; however, at the end of a certain time, chlorine is 
found in the receiver, carbonic acid and azote, and the gaseous mixture 
gives out the odour of chloride of cyanogen. 
Common carburetted hydrogen does not act upon chlorous acid ; but 
this acid and bicarburetted hydrogen decompose each other, without 
evolving heat and light, water and a chloride of carbon being produced. 
Phosphuretted and arseniuretted hydrogen gases, on the contrary, 
occasion detonation, and the gaseous residue found is chlorine mixed 
with a little oxygen. The combination of sulphuretted hydrogen is 
accompanied with a blue flame, similar to that afforded by sulphur 
when it is burnt in contact with the air. The detonation produced by 
ammonia is also very vivid, and, in this case like the former ones, much 
chlorine is set free. 
Sulphuret of carbon also produced a vivid explosion, after which 
there was found in the receiver in which it occurred, chlorine, sulphurous 
and carbonic acid. The odour of these gases indicates that there is 
formed at the same time a small quantity of chloride of sulphur. 
The decomposition of chlorous acid by hydrochloric acid is accom- 
panied with the disengagement of heat only, without producing light. It 
is the same when hydriodic acid is operated with. 
Phosphuret of lime [ calcium? ] instantly occasions the decomposition 
of chlorous acid with a loud detonation, and the gaseous residue con- 
tains much chlorine. ; 
The greater number of sulphurets—those of barium, tin, mercury, 
antimony, &c.—produce in a few seconds the same effect. When there 
is but little gas it may be absorbed without the occurrence of detona- 
tion. In the latter case, the odour indicates the formation of chloride 
of sulphur. i 
Oxalic acid also decomposes chlorous acid without producing ex- 
plosion. Oxide of carbon, upon which the liquid acid did not appear 
to exert any action, decomposes chlorous acid gas but slowly. After 
the lapse of some hours the colour of the mixture disappears, and the 
