THE CAUSTIC ALKALIES AND THEIR CARBONATES; POTASH, SODA, AMMONIA.
The second division of the class of Corrosives has now to be considered.
It contains the Caustic Alkalies, and some of their Salts. Poisoning by
any of these agents is rare.
POTASH.--This substance, in its caustic state, as found in commerce, is
in the form of grey-colored cakes. It has an acrid taste, is soapy to
the touch, and very deliquescent. Moulded in cylinders, it is often
employed as a caustic (Potassa fusa). In solution (Liquor potassae) it is
strongly alkaline, and imparts a brown stain to black cloth.
_Potassium carbonate_ or _Carbonate of Potash_ (Pearlash) is extensively
used by laundresses and in the dressing of woollen cloth. It is
generally sold in a granular condition, white, inodorous, and strongly
alkaline; it is soluble in water, but not in alcohol.
CAUSTIC SODA.--This agent resembles potash in its general properties.
The _Sodium Carbonate_ or _Carbonate of Soda_ (Soap-lees) bears a
similar resemblance to the carbonate of potash, except that it
crystallizes easily, and effloresces on exposure to the air.
AMMONIA.--When pure, ammonia is a colorless, pungent gas; but it is
commonly met with dissolved in water, as the liquor ammoniae. Its vapor
is poisonous, and may prove fatal by producing inflammation of the
larynx and trachea, and even of the lungs. A case is recorded of a
French boy, aet. six, who killed his younger sister by making her swallow
several teaspoonfuls of a solution of ammonia. Other instances have also
occurred where the liquor ammoniae has either been taken in mistake for
the aromatic spirit of ammoniae, or purposely, to destroy life. An
instance is recorded by Dr. Taylor, as occurring in the practice of Mr.
Hilton, where liquor ammoniae, given by mistake, caused corrosion of the
throat and gullet and obstruction of the bronchial tubes by false
membrane. The oesophagus was completely dissolved at its junction with
the stomach, and there was an aperture in the anterior wall of that
organ such as might have been caused by oil of vitriol.
The _Ammonium Carbonate_ or _Carbonate of Ammonia_ (Hartshorn, Smelling
Salts) has been used as a poison. It may be distinguished from other
salts by its being alkaline, by its entire volatility, and by its
pungent odor. A young woman in a state of unconsciousness, was made to
swallow a quantity of hartshorn. In an hour there was great pain,
sickness, and vomiting of blood. The haematemesis continued for some
days, and then feebleness and emaciation set in, death occurring in
three months. On examination the pylorus was found contracted to the
size of a crow-quill, while there was a large cicatrix on the posterior
wall of the stomach.
_Symptoms._--The chief symptoms occasioned by the foregoing poisons are,
an acrid, burning taste, with a sensation of excoriation and burning
extending along the mouth and throat, to the stomach. There soon ensue
exquisite pain in the epigastrium, and tenderness on pressure.
Frequently there is cough, hoarseness, dyspnoea, as well as vomiting
of altered mucus mixed with blood and detached portions of the mucous
membrane. The tongue, mouth, and fauces become swollen, soft, and
flabby, and deglutition is difficult. The surface of the body gets cold
and moist, the pulse small and feeble, and there is great pain over the
abdomen, with diarrhoea. Death took place, in the case of a boy, in
three hours from the time of swallowing a strong solution of carbonate
of potash. Ammonia, by its effect on the air passages, has proved fatal
in four minutes. When recovery from the immediate effects of the poison
has taken place, death has subsequently ensued from stricture of the
oesophagus, producing starvation. By the proper use of bougies, &c.,
life may occasionally be prolonged for many months, or even for years.
In some instances, however, it is almost impossible to effect
dilatation, owing to the whole of the gullet becoming thickened and
contracted, so that the opening into the stomach will hardly admit a
crow-quill. The pylorus may also be contracted in like manner.
_Post-mortem Appearances._--The mucous membrane of the mouth and gullet
is softened and inflamed, and portions of it detached. The coats of the
stomach and intestines are inflamed, stained of a dark color, and
sometimes ulcerated. When death has resulted from ammonia, signs of
inflammation are usually found in the larynx and bronchial tubes. The
other caustic alkalies may also destroy life by producing inflammation
of the glottis, which consequently may be found thus occluded after
death.
_Treatment._--The object must be to neutralize the poison, which may be
effected by a weak acid. Vinegar and water is perhaps the best
antidote, and that most readily procurable; its administration may be
followed up by freely allowing acidulated demulcent drinks, orange
juice, &c. The use of oil has been recommended, on the principle that it
converts the alkali into a soap. But that its efficacy is doubtful has
been in some measure shown by the death of two young children from
swallowing a mixture of ammonia and oil. In one of these cases nearly
two ounces of linimentum ammoniae (made of one part of liquor ammonia to
two of olive oil) were poured down an infant's throat by a child five
years old. Were, however, the oil given in much greater abundance, the
result would probably be different. At all events, its administration
should not be neglected.
_Tests._--The specific character of these substances is their strongly
marked alkalinity, ammonia possessing, over and above, that of
volatility. Potash is known from soda by being precipitated of a creamy
yellow by platinum perchloride, soda remaining unaffected by that
reagent.
II.--SIMPLE IRRITANTS.