We have already stated by what chemical reagents this alkali may be
distinguished from _potass_; it only remains for us to observe that its
physiological action, the symptoms arising from its ingestion, and the
organic lesions discovered on dissection, are strictly analogous to
those we have described as the effects of potass.
AMMONIA, and its CARBONATE.
Ammonia, in its uncombined state, exists in the state of gas, and is
incapable of application; its affinity, however, for water, enables it
to combine with that fluid, and to form liquid ammonia, (_Liquor
Ammoniæ_) in which state it is useful in medicine, and in the arts. This
solution is colourless; its taste extremely caustic; and its odour
strong, pungent, and peculiar. Exposed to the action of heat, the
ammoniacal gas is driven off, and may be recognised by its
characteristic odour, as well as by its effects upon moistened
_turmeric_ paper. When brought into contact with muriatic acid, it will
form dense white vapours, consisting of _muriate of ammonia_. A most
elegant and sensible test for ammoniacal gas is afforded by a mixed
solution, consisting of arsenious acid and nitrate of silver; these
substances when mixed in solution do not occasion the least disturbance
in each other, for reasons already explained, (see page 240) but upon
spreading a portion of the liquid upon glass or paper, and bringing
ammoniacal gas into contact, a beautiful yellow cloud immediately
diffuses itself over the surface of the solution.
_Sub-carbonate of ammonia_ occurs in solid, white, semi-transparent
masses, of a highly pungent and ammoniacal odour. Its chemical
composition has been found to vary materially according to the
circumstances under which it has been prepared; _Mr. R. Phillips_, who
has made some highly interesting experiments upon this subject,
considers the _sub-carbonate_ to be a _sesqui_-carbonate, composed of 3
atoms of carbonic acid, 2 atoms of ammonia, and 2 of water. By long
exposure to the air, its pungency is lost, and it is converted into an
inodorous carbonate.
_Symptoms of poisoning by Ammonia._
Cases wherein death has been produced in a few minutes, from the
ingestion of liquid ammonia, stand recorded on the authority of
_Martinet_, _Huxham_, _Haller_, and other physiologists. In such cases
the lips, tongue, and fauces are described as being burnt by the
causticity of the fluid; while hemorrhage of the intestines marks the
organic lesions which it occasions. The nervous system would appear also
to suffer greatly, at the same time that the abdominal organs are
affected with violent inflammation.