But it has been supposed that certain bodies, as glass, enamel, diamonds,[[138]] agates, smalt, &c. when administered in the form of powder, so lacerate the membranes of the stomach, by the sharpness of their particles, as slowly to destroy life; and upon the same principle, it has been asserted, that human hair, chopped fine,[[139]] constitutes the active ingredient of a slow poison frequently employed in Turkey, and that it induces, by irritation, a chronic disease resembling cancer. With respect to the danger arising from the ingestion of diamond dust, enamel powder, powdered glass, and the like, there still may be said to exist some difference of opinion. Caldani, Mandruzzato,[[140]] and M. Le Sauvage, have reported experiments made upon men and inferior animals, in which no bad consequences followed the administration of such bodies; whereas Schurigius[[141]] and Cardanus[[142]] cite instances where persons have died of ulcerations of the stomach from such causes; and this opinion receives the support of Plouquet,[[143]] Stoll,[[144]] Gmelin,[[145]] Foderé,[[146]] Mahon,[[147]] Franck,[[148]] and many others. The modern pathologist will not find much difficulty in reconciling such conflicting testimony. The experimentalist may administer mechanical substances a thousand times without producing any ill effects, while, under certain circumstances, the most trivial body may lodge in the intestines and produce death; but surely the occasional occurrence of such accidents ought not to confer the general title of poison upon the substances which may happen to produce them.
Having thus disposed of a considerable number of bodies, which have been classed as slow poisons, we may proceed to observe that most of the other substances which have found a place in the same division, appear to us to deserve consideration under a very different head, and that we shall get rid of much obscurity by adopting the following arrangement.
2. Consecutive Poisoning. Where the patient, having recovered from the acute effects occasioned by the ingestion of a single dose of poison, subsequently suffers a series of symptoms from the injured structure to which it had given origin. By referring to our definition of slow poisoning, we shall at once perceive the striking and important distinction between that and Consecutive poisoning. The following case, related by M. Orfila, may serve as an illustration. Maria Ladan drank by mistake a spoonful of Aqua fortis, the most violent symptoms supervened, but which by judicious treatment gradually subsided, when at length she passed by stool a long membranous substance, rolled up, and which represented the form of the æsophagus and stomach, and which, in fact, was found to be the interior membrane of these organs; from that moment the sensibility of the digestive organs became excessive, and two months after the accident she experienced a sudden shock and died. M. Tartra, in observing upon cases of this kind, asserts that the symptoms produced at first by the nitric acid decrease insensibly; and that at the end of a certain period, the internal membrane of the digestive canal is struck with death, and thrown off, and the person dies of a Marasmus. Fordyce[[149]] relates the case of a woman who was subject to cholics for the space of thirty years, in consequence of having once taken an infusion of the pulp of Colocynth prepared with beer. This was undoubtedly an extraordinary instance of idiosyncrasy, but it is probable that some organic lesion was occasioned by its operation, to which the subsequent suffering is to be referred. We have hitherto only considered the effects that may arise from the ingestion of a single dose of poison, but there are numerous and very interesting cases in which fatal results have been produced by the repetition of small doses at various intervals. We therefore propose a third, and new subdivision of our subject, viz.
3. Accumulative Poisoning.—By the repeated administration of a substance, in doses, of which no single one could occasion harm; but which, by gradually accumulating in the system, ultimately occasions disease, and death.
The familiar operation of mercury will at once suggest itself to the Physician, as a striking illustration of that species of poisoning which we have ventured to name Accumulative, and to the forensic student the effects of this metal, in reference to such a quality, will form a more than ordinary object of interest, as involving questions which have frequently embarrassed judicial inquiry; as, for instance, Whether it can lie dormant any considerable time without betraying its effects upon the constitution, and, having displayed its powers, and the symptoms having subsided, viz. salivation, &c. Whether they can be renewed without a fresh application of the substance? See Corrosive sublimate.
To how many substances this power of accumulation extends is at present not well understood. It may occur in those that act by absorption, and in those whose action is wholly local. Arsenic, digitalis, and several of the narcotic plants, as hemlock, may undoubtedly occasion serious mischief in this manner, as the author has more fully explained in another work,[[150]] and we have lately heard of several fatal cases arising from accumulated masses of magnesia in the primæ viæ, from the habitual use of small doses of that earth.
The history of many of the arts, especially those of metallurgy, would furnish also abundant examples of this kind of poisoning.
These few facts are we trust sufficient to authorise the foregoing arrangement, and we apprehend that the adoption of the distinctions, upon which it is founded, will be of great service in establishing fixed and definite notions with regard to the chronic operation of poisons. It may perhaps be useful to present the reader with a synoptical recapitulation of the subject.
A Slow Poison. A single dose is sufficient; which produces upon its administration no sensible effect, but gradually undermines the health.
A Consecutive Poison. A single dose is sufficient; producing the most violent symptoms, very shortly after its ingestion, but which gradually subside, and the patient is supposed cured; when, at some future period, death takes place from the organic lesions that had been occasioned.