This acid, when perfectly pure, exists in the form of a colourless
liquid, without smell, and of an oily consistence; whence its popular
name. Its specific gravity is 1·85, so that, in round numbers, it may be
stated that an ounce, by measure, will weigh fourteen drachms. It
acquires a brown tinge from the smallest portion of carbonaceous matter;
mere exposure to the atmosphere is sufficient to effect this change, in
consequence of the acid disorganizing and carbonating the vegetable and
animal matter suspended in the air. This fact sufficiently explains why
we generally find the acid of commerce of a brown colour.
Its taste is highly acid and caustic. So powerful is its affinity for
water, that upon its admixture with this fluid, a heat, sufficiently
great to boil water, may be produced. When exposed in its concentrated
state to the air, it will imbibe at least seven times its own weight of
water, and so rapidly as to have its weight doubled in a month. Straw,
wood, and all vegetable substances, when immersed in the sulphuric acid,
without heat, are disorganized, softened, and blackened, and there is
separated from them a certain portion of charcoal. Like the other
mineral acids, the _Oil of Vitriol_ has never been obtained in an
insulated state without water; according to the latest views of _Sir H.
Davy_, the composition of the strongest acid may be expressed as
follows. Sulphur 30, oxygen 45, water 17.
_Symptoms of Poisoning by Oil of Vitriol._
An extremely austere, acid, and burning taste; a painful heat in the
fauces and throat, along the œsophagus, and in the stomach; excruciating
pain; nausea, and excessive vomiting; at one time the fluid vomited is
as black as ink, at another reddened by arterial or venous blood,
producing in its passage through the throat, the most intense pain,
accompanied with a sensation of bitterness quite intolerable; if, by
chance, a portion of it should fall on the hearth or pavement, or on any
other calcareous substance, it will denote its true nature by an
effervescence; constipation, or sometimes bloody stools; gripes and
excruciating pains over the abdomen, with a tenderness of these regions,
so exquisite as not to allow the slightest pressure without torment;
pains of the breast; difficulty of breathing; extreme anxiety; the pulse
becomes frequent, small, contracted, and irregular; shiverings; great
restlessness, dejection, and agitation; convulsive motions of the
countenance; sometimes a cutaneous eruption betrays itself. Amidst all
these symptoms, the intellectual powers remain unobscured. The parts
about the fauces, the uvula, &c. having lost their vitality, slough, and
become detached, which occasion an indescribable fetor of the breath,
while they produce a perpetual cough, and the voice becomes so altered,
that it resembles the sounds of a person labouring under croup.
_Organic lesions discovered on Dissection._
As this substance destroys life by simply acting as an escharotic, it is
not difficult to anticipate the disorganization which dissection will
display. The extent of the lesion, however, must in every case depend
upon the quantity and degree of concentration of the acid, the state of
the stomach in relation to its alimentary contents, and other incidental
circumstances not to be exactly appreciated. The mucous membrane of the
mouth, the tongue, and œsophagus, will in general be found destroyed,
and converted into a pulp.
_Antidotes._
The great indications to be fulfilled in this distressing case, is the
immediate dilution, saturation, and expulsion of the poison. Copious
draughts of water, holding calcined[321] magnesia in suspension, should
be administered without any loss of time. If this is not in readiness,
soap and water should be administered; mucilaginous drinks, milk, and
even warm or cold water, in the absence of more eligible potations,
should not be neglected. It must be never forgotten, exclaims _Orfila_,
that success upon these occasions depends upon the activity of the
practitioner; the delay of a few moments will entirely change the fate
of the patient, as the sulphuric acid destroys the texture of the organs
with a fearful celerity. After having thus neutralized the caustic, it
will be our duty to obviate the effects it may be likely to occasion;
the lancet must be used with boldness, and the detraction of blood
repeated at short intervals; at the same time emollient clysters may be
advantageously injected.
_Chemical processes for the detection of Oil of Vitriol._
In the pure state, there can exist no difficulty in identifying it; its
specific gravity, and its action on vegetable matter, will, without any
other tests, be quite sufficient to fulfil our object. If heated with
metallic mercury, it will disengage sulphurous acid gas; and if united
with lime, a sulphate of lime will be produced, which the chemist may
easily recognise by dissolving a portion in distilled water, and
assaying the solution by _muriate of baryta_, which will produce with
the sulphate a precipitate, insoluble in nitric acid. By the last
mentioned tests we shall be enabled to detect the presence of sulphuric
acid, in whatever state of complication it may happen to exist with
alimentary matter.