This opinion receives further strength when it is considered how frequently poisons were administered under the insidious form of charms or incantations.[[128]]
It has, however, been shewn by late experiments that the toad has, under particular circumstances, the power of ejecting from the surface of the body an acrid secretion which excoriates the hands of those that come in contact with it; and this fact may perhaps have assisted in supporting the general belief respecting the poisonous nature of this reptile. Pelletier has ascertained, that this corrosive matter, contained in the vesicles which cover the skin of the common toad, (Rana Bufo) has a yellow colour, and an oily consistence, and to consist of,—1st, an acid partly united to a base, and constituting 1/20th part of the whole. 2d, very bitter fatty matter. 3d, an animal matter bearing some analogy to gelatine.
It would also appear from the writings of Dioscorides, Galen, Nicander, Ætius, Ælian, and Pliny, that the ancients derived a very energetic poison from the Sea Hare, Lepus Marinus,—the Aplysia Depilans of Linnæus; and, if we may credit Philostratus, it was with such a poison that Titus was killed by Domitian.
There is, however, ample ground for supposing that the poisons of the ancients were, for the most part, obtained from the vegetable kingdom, and from the class of Narcotic plants;[[129]] that they were compounded of a great variety of such ingredients, together with others that were quite inert and useless, and which merely served to disguise their composition.
Ancient writers also allude to the blood of the bullock as a poison; Themistocles is said by Plutarch to have destroyed himself by this fluid; and Strabo states that Midas died of drinking the hot blood of this animal, which he did, as Plutarch mentions, to free himself from the numerous ill dreams which continually tormented him. Some historians assign the death of Hannibal to the same draught.
With respect to the poisons employed by Tophana, the Locusta of modern days, and her infamous successors, there is less doubt; Arsenic, Corrosive Sublimate, Sugar of Lead, and Antimony,[[130]] were amongst the most powerful of their instruments of torture and death. According to the declaration of the Emperor Charles VII to his physician Garelli, the Aqua Toffania was a solution of arsenic in Aqua Cymbalariæ.[[131]] Dr. Hahneman considered its basis to have been an arsenical salt. Others have, with little probability, regarded Opium and Cantharides as the active ingredients. Franck,[[132]] speaking of the Aqua Toffania, agrees with Gmelin,[[133]] that it is no other than a solution of arsenic. The Pulvis Successionis, another instrument of death, whose title announces the diabolical intention with which it was administered, has been supposed to have been a preparation of lead; while others have considered it to have consisted of diamond dust, and to have acted mechanically.
Having thus noticed a few of the more remarkable and interesting features in the literary history of Toxicology, we shall proceed to consider the subject of Poisons, in relation to their operation.
A Poison, (Toxicum, Venenum, Virus), has been very correctly defined by Gmelin to be a substance which when administered internally, or applied externally, in a small dose, impairs the health, or destroys life. This definition is adopted by Mead, Sproegel, Plenck, and Tortosa, and is to be preferred to every other,[[134]] not only for its simplicity, but for its independence of any theory relative to the modus operandi of such agents. But it will be seen that, by accepting this definition, we are necessarily led to admit the fact, that poisoning may be acute, or chronic, that is to say, that it may at once destroy life, or produce a disease which can be protracted to any indefinite period. After the erroneous and vague notions which have been entertained upon the subject of “Slow poisons,” it is highly essential that the latitude of our belief should be accurately ascertained, and the precise meaning of our terms defined.
OF SLOW, CONSECUTIVE,[[135]] AND ACCUMULATIVE POISONING.
1. Slow Poisons. According to the popular acceptation of the term, they may be defined, Substances which can be administered imperceptibly; and a single dose of which will operate so gradually, as to shorten life like a lingering disease; their force, at the same time, admitting of so nice an adjustment as to enable the artist to occasion death at any required period. We have now to inquire how far such alleged powers are consistent with the known laws of physiology. It cannot be denied that certain substances have been introduced into the alimentary canal, where they have remained for an indefinite period, without occasioning the slightest inconvenience, and at length excited a disease that has terminated fatally; in the London Medical and Physical Journal for February 1816, a case is related in which death was occasioned by a chocolate-nut having lodged in the entrance of the Appendix Vermiformis; and in the Edinburgh Medical and Surgical Journal for July 1816, we have an analogous case, communicated by Dr. Briggs of Liverpool, where the Appendix cæci sphacelated, owing to the irritation of a human tooth which was found sticking in its cavity. Mr. Children has lately communicated to the Royal Society a case where a concretion in the colon produced death; upon examination it was found to contain a plum-stone, as a nucleus, and to consist of a fine fibrous vegetable substance, from the inner coat enveloping the farina of the oat, and which was derived from the oatmeal upon which the deceased had fed. (Phil. Trans. 1822.) However disposed we may feel, by a forced construction of the term, to consider such agents as slow poisons, it is very evident that they can rarely have been made subservient to the purposes of secret poisoning; although a case occurred in the practice of the author,[[136]] in which a girl swallowed six copper pence for the avowed purpose of destroying herself; the coin produced a disease which remained chronic for a very considerable period, when, after a lapse of five years, they were voided, and the young woman recovered. A similar attempt was also made by Theodore Gardelle, after his conviction for the murder of Mrs. King (vide ante), he swallowed a number of halfpence, for the purpose of destroying himself, but without any ill effect. Dr. Baillie, in his ‘Morbid Anatomy,’ relates an instance where five halfpence had been lodged in a pouch in the stomach for a considerable time, without occasioning any irritation; and Mr. A. Thomson has also furnished us with two analogous cases in children, in one of which the copper coin remained six months in the intestines, and in the other, two months. These facts furnish sufficient data to enable the practitioner to appreciate the degree of danger attendant upon such agents, and to determine how far they can ever become successful instruments in the hands of the assassin.[[137]]