CAROLINE.
True; I recollect perfectly that hydrogen detonates with oxygen when the two gases are converted into water.
MRS. B.
But let us return to the nitrat of potash.—This salt is decomposed when exposed to heat, and mixed with any combustible body, such as carbon, sulphur, or metals, these substances oxydating rapidly at the expense of the nitrat. I must show you an instance of this.—I expose to the fire some of the salt in a small iron ladle, and, when it is sufficiently heated, add to it some powdered charcoal; this will attract the oxygen from the salt, and be converted into carbonic acid.—
EMILY.
But what occasions that crackling noise, and those vivid flashes that accompany it?
MRS. B.
The rapidity with which the carbonic acid gas is formed occasions a succession of small detonations, which, together with the emission of flame, is called deflagration.
Nitrat of ammonia we have already noticed, on account of the gaseous oxyd of nitrogen which is obtained from it.
Nitrat of silver is the lunar caustic, so remarkable for its property of destroying animal fibre, for which purpose it is often used by surgeons.—We have said so much on a former occasion, on the mode in which caustics act on animal matter, that I shall not detain you any longer on this subject.