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CHAPTER XVIII
POISONS
Poisoned arrows – Fish poisons – Manchineel – Curare – A wonderful story – Antiaris – Ordeals – The Obi poison – Oracles produced by poisons – Plants which make horses crazy and others that remove their hair – Australian sheep and the Caustic Creeper – Swelled head – Madness by the Darling Pea – Wild and tame animals, how they know poisons – How do they tell one another? – The Yew tree, when is it, and when is it not poisonous?
EVEN to-day all embryo chemists and doctors are required to "pass" in the recognition of the more important medicinal plants.
But their knowledge is probably very superficial as compared with that of a bushman in the Kalahari Desert of South Africa. Every man, woman, and child in such a tribe knows thoroughly every plant that grows in the neighbourhood. His diet is a varied one, for it includes maggots, fish, frogs, snakes, white ants, and other horrible ingredients, but he lives mainly on roots, bulbs, and herbs of sorts. In times of famine he has had to obtain the most intimate knowledge possible of many plants, that namely which is obtained by eating them, and he has most carefully observed the poisonous kinds. These latter have given him, too, a very powerful weapon, for it is the poisoned arrows which give him the chance of killing game, otherwise utterly beyond his reach. He is on the fair road to becoming a hunter and tribesman, instead of being only a member of a morose, outcast family, always wandering and always hungry.
Probably poisons were first used in fishing. Many vegetable drugs, when thrown into pools and lakes, have the property of stupefying or killing the fish. A great many of these fish poisons are known, and it is quite easy to use them.
Amongst the Dyaks of Borneo, screens of basketwork are placed along a stream to prevent the fish escaping. Then the Dyaks collect along either bank in their canoes. Everybody has a supply of the root of the tubai (Menispermum sp.), which they hammer with stones in the water inside the canoe, so as to extract the poison. At a given signal the poisonous stuff is baled into the river, and very soon afterwards a scene of wild excitement begins, for the fish are speared or captured with handnets as they rise, stupefied, to the surface. The women scoop up the small fry in their nets.107
Even at the Sea of Galilee, Tristram mentions that Arabs sometimes obtain their fish by poisoned bread-crumbs. In the South Sea Islands, at Tahiti, a poison is obtained from the nuts of a kind of Betonica, and is used to catch the fish among the reefs near shore.108 In West Africa several fish poisons are in use (e.g. seeds of Tephrosia Vogelii), and probably the same methods are used almost everywhere. They are by no means extinct even at home, for the occasional poacher sometimes uses fish poisons.
Arrow poison is, however, much more important, and is used by a great number of tribes in almost every part of the world. In 1859, in a war with the Dyaks of Borneo, the English army lost thirty men by poisoned arrows. They are deadly weapons, for the dart is a very thin piece of reed or cane, which has been dipped in the Upas poison (Antiaris toxicaria). It is propelled from a blow pipe, which in practised hands is able to carry 250 feet. One or two of these darts may cause death in two hours' time. The Spaniards, in their conquest of the West Indian islands, were often defeated by the poisoned arrows of the Caribs. The wounded died in agonies of suffering and delirium, sometimes protracted for twenty-four hours after receiving the wound.
The poison in this case is supposed to have been the Manchineel (Hippomane).
It is a handsome tree, but a very dangerous one, for the slightest cut on the surface produces a flow of a very fine white milk which is acrid and poisonous. This juice produces temporary or total blindness if the slightest speck enters the eyes, or even if one sits over a fire made of its wood. It is probably not true that people are killed if they merely sleep below it, and grass will probably grow quite well under its shade, although there are stories which deny this. Blowpipes and poisoned darts are used by many savages in Asia and South America. Perhaps the Curare or Woorali poison is the most wonderful of the South American kinds. The tree, Strychnos sp., grows along the Amazon and in the Guianas. The poison is obtained from the wood and bark, and several other vegetable substances are mixed with it. (This is a very common feature of native drugs and increases the chances of doing something.) It is a blood poison, and a very deadly one. Large animals like the tapir stagger about, collapse, and die after a very few steps, if they have been wounded by a dart. Humboldt declares that the earth-eating Otomaks were able to kill their antagonists by the mere pressure of their poisoned thumbnails.
In Africa it is more usual to find poisoned arrows shot from a bow. The exquisitely beautiful seed of Strophanthus Kombe is used as an arrow poison. The plant is a climber found in forests or bush, and has large woody pods about seven to twelve inches long. When these are open, the inside is seen to be full of the small yellowish seeds; each ends in a fine awn three to four inches long, which carries at the end a beautiful tuft of the finest silky hairs. The seed-coat is also covered with silk hairs. When viewed against a black surface, there is no more lovely object in nature. Yet from the seed-coat a very deadly poison is obtained; probably snake-venom and various gluey substances form part of the mixture, which is daubed on the arrows. Dr. Kolbe saw the Hottentots plastering their arrows with the poison of the hooded snake. Bushmen use a Lily bulb, Haemanthus toxicarius, but sometimes add part of the inside of a small caterpillar.
Another African poison which is not so well known is the Acokanthera, which was the ingredient in the arrows obtained by the writer in British East Africa.
North America is singularly free from these unsportsmanlike and horrible weapons, but they were not unknown in Europe in very ancient times. Pliny speaks of the Arabian pirates as poisoners, and allusions to their use of deadly arrows can be found in Horace, Ovid, and Homer. In the Odyssey, the hero goes to Ephyra (Epirus?) to purchase a deadly arrow poison, but he is refused for fear of the eternal gods. Poisoned arrows were employed by the Celts in Gaul, and also by the Saracens in the War of Granada in 1484.
Yet even in the time of Homer the sense of humanity seems to have decided against poisoned arrows as being both unnecessary and cruel, just as, in our own times, explosive bullets have been condemned, and are no longer used by civilized nations. But we should remember that until man became so expert with the bow and spear and so civilized by tribal fights as to be able to do without poisons, they were a very useful help in the struggle for civilization. Hundreds of thin pieces of bamboo about six inches long were regularly carried by certain African tribes. When dipped in poison and afterwards placed in paths in the ground, they formed a very efficient protection against barefooted enemies.
The Antiaris alluded to above is the famous Upas tree of Java. The tree was said to grow in a desert with not another living plant within ten miles of it. Such was the virulence of its poison that there were no fish in the waters. Neither rat, nor mouse, nor any other vermin had ever been seen there; and when any birds flew so near this tree that the effluvia reached them, they fell dead – a sacrifice to the effects of its poison. Out of a population of sixteen hundred persons who were compelled, on account of civil dissensions, to reside within twelve or fourteen miles of the tree, not more than three hundred remained alive in two months. Criminals condemned to die were offered the chance of life if they would go to the Upas tree and collect some of the poison. They were provided with masks (not unlike our modern motor-veils), and yet not two in twenty returned from the expedition.
All the foregoing statements were for years implicitly believed. They were vouched for by a Dutch surgeon resident in Java. Medicine is a profession, and Holland is a country which would in no way lead one to expect such magnificent mendacious audacity!
For the whole of the preceding statements about Antiaris is pure romance. The inner bark of young trees, when made into coarse garments, produces an extremely painful itching, whilst the dried juice is a virulent arrow poison.
Hellebore and Aconite were the favourite poisons of the Marquise de Brinvilliers and other specialists of the Middle Ages. The Christmas Roses or Hellebores were known to be poisonous fourteen hundred years before the Christian era, and are still used in medicine. Aconite, which has a tuberous root-stock, is dangerous, for it is occasionally eaten in mistake for the horse-radish, to which it has a faint resemblance. All kinds of aconite are poisonous. That of one of the Indian species is used to tip the arrows employed in shooting tigers.
Trials by ordeal were very common in ancient times. The theory was that an innocent person was not injured by certain drugs, which, however, proved immediately fatal to the guilty.
Such trials at one time were customary in almost every part of the world. They were supposed to be perfectly just, so that no man could be held guilty of the death of those who succumbed. In practice, however, they were almost invariably corrupt. The Tanghinia venenifera of Madagascar was regularly used in ordeals, and is probably still employed by certain tribes. The seeds are exceedingly poisonous, but, if the authorities wish the accused person to escape, a strong emetic is mixed with the powdered seeds, and the poison has no time to act. This, however, is seldom the case, for in any savage nation no one who is popular and in good esteem with the king or other people in authority is at all likely to be accused. The fact of his being accused means in most cases that he is already condemned to die. Another ordeal plant is the Calabar Bean (Physostigma venenosa), found in West Africa. The plant is a climber belonging to the Leguminosæ, and the seeds, which are about an inch in diameter, are very deadly. The seed is conspicuously marked by the long, dark, sunken scar, where it was attached to the pod. Besides being exceedingly poisonous, it has also a curious effect upon the pupil of the eye, which is contracted by this drug.109
Another famous poison is produced from Datura stramonium and allied species. In tropical and sub-tropical countries, one is almost sure to find specimens of this handsome plant along almost every roadside. It is in fact one of the commonest tropical weeds. The leaves are large with fine spinose margins, and the flower is most conspicuous, as it is four or five inches long. This is supposed to be one of the drugs employed by the Obi wizards and witches. The most horrible rites, accompanied by atrocious cruelties, were performed amongst certain West African tribes and are continued amongst their descendants, the freed slaves of the West Indies and of the Southern United States.
Even to-day no white man is allowed to learn anything of the proceedings, but some form of devil-worship or Shamanism, accompanied by incantations and the use of poisonous drugs, still flourishes. Preparations of various sorts of Datura or Thorn-apple produce sometimes stupefaction, sometimes frantic, furious delirium, and sometimes death.
It is used in medicine as a narcotic and diuretic. Burton says that the Arabs smoke the leaves in pipes as a cure for influenza and asthma. It is sometimes used in Europe for neuralgia and even epilepsy. On the other hand, the priests of the ancient Peruvians used Datura to produce the ravings mistaken for inspiration, and it is supposed that the priests of Apollo at Delphi employed an allied species for the same purpose. In India, China, West Africa, and amongst the American blacks, it is still very commonly used.
A firm belief existed in the Middle Ages that every plant was a good remedy for something. There is a real basis in fact for this superstition, because every plant in the world has, so far as it can do so, to protect itself. The attacks of all sorts of grazing animals, from the mouse to the elephant, as well as the infinitely more dangerous and destructive insects, bacteria, and fungi, have to be provided for. By far the commonest form of protection is to develop within the plant strong medicinal or strongly smelling substances. These are far better as protective agents than the thorns and spines characteristic of deserts and half-deserts. We have already glanced at the turpentines and resins of Coniferous forests and at the odorous gums, frankincense, and myrrh of the Acacia scrub.
The use of poisons as protection is eminently characteristic of three of the natural orders. The Buttercups (Ranunculaceæ), the Potato order (Solanaceæ) and the Lilies. Of the first named, the celery-leaved, and indeed all Buttercups, are extremely poisonous; so also are all Aconites and Hellebores, as well as Marsh Marigold, Adonis, Clematis, and Larkspur.
Others, though not poisonous, are strongly medicinal, such as Blake Snakeroot, Hydrastis, etc. It is therefore inadvisable to use any of this order for food unless other people have eaten it without any inconvenience!
The beauty of the Lily order does not prevent it from being a particularly dangerous group of plants. Perhaps the worst poisons in this order are those of the Meadow Saffron (Colchicum autumnale), Herb Paris, Veratrum, Sabadilla, Lily of the Valley, Tulip, and Crown Imperial bulbs. Chamælirium, Trillium, Squills, Garlic, Solomon's Seal, Aloes, and the Sarsaparillas are all well-known medicines.
The order Solanaceæ is perhaps the most interesting, for it includes such dangerous poisons as Tobacco, Datura, Atropa belladonna (Deadly Nightshade), Henbane, Bittersweet (Solanum dulcamara), Common Nightshade (Solanum nigrum), and a very great many important drugs. Even the common potato contains a poisonous secretion solanin, and it is dangerous to eat green potatoes or the foliage. Yet the Tomato or Love Apple (so called because it was supposed to excite tender feelings) is both nutritious and delicious. Chillies and Cayenne Pepper (Capsicum spp.) are also commonly used as condiments.
Such poisonous orders should of course be avoided, but much more dangerous are those deadly plants which appear as it were accidentally in orders which are amongst the most useful friends of man. Amongst the grasses there is the deadly Darnel (Lolium temulentum), a first cousin and not very unlike the very commonest and one of the most useful grasses – Rye Grass (Lolium perenne).
Then in the useful Carrot order, there are such dangerous and even deadly plants as Fool's Parsley, Water Dropwort, and Cowbane. Œnanthe crocata (Water Dropwort) is one of the very commonest marsh and ditch plants in Great Britain. It is perfectly well known to botanists as distinctly poisonous, yet in 1902 a veterinary surgeon brought me some of the tuberous roots to name, and told me that six fine young cows were lying dead on a neighbouring farm through having eaten them!
A particularly useful order of plants (Leguminosæ), the Beans and Peas, contains a few poisonous species. It is said that in every year children are sure to be killed by eating the seeds of the Laburnum, and to this order belong also the Calabar Bean and Crab's Eyes. The last named is only fatal when introduced below the skin in small quantities. The seeds of the Bitter Vetch (Lathyrus sativus) produce paralysis of the legs in man and also in horses. The Crazy or Loco weed of North America is sometimes eaten by horses in the Western United States. The wretched animals stagger about as if intoxicated, and eventually die. Belonging to this same order is the Wild Tamarind, or Jumbai, of Jamaica (Leucæna glauca). It is a weedy-looking acacia, and extremely common in all tropical countries. Dr. D. Morris thus alludes to it: —110
"Mr. Robert Russell, of St. Ann's, informs me that horses feeding on the leaves of this plant completely lose the hair from their manes and tails. This … statement was supported by the testimony of so many people acquainted with the facts that there was no reason to doubt it. Many years afterwards (in December, 1895), I renewed my acquaintance with the plant in the Bahamas. The plant was much more plentiful there than in Jamaica; it was, in fact, distinctly encouraged in the former islands as a fodder plant. The people were fully aware of the singular effect it produced on horses, and added that it also affected mules and donkeys. Its effect on pigs was still more marked. These animals assumed a completely naked condition, and appeared without a single hair on their body. Horses badly affected by Jumbai were occasionally seen in the streets of Nassau, where they were known as 'cigar-tails.' Such depilated animals, although apparently healthy, were considerably depreciated in value. They were said to recover when fed exclusively on corn and grass. The new hair was, however, of a different colour and texture, 'so the animals were never quite the same.' One animal was cited as having lost its hoofs as well, and in consequence it had to be kept in slings until they grew again and hardened. The effects of the Jumbai on horses, mules, donkeys, and pigs were regarded as accidental – due to neglect or ignorance. The plant was really encouraged to supply food for cattle, sheep, and goats. The latter greedily devoured it and were not perceptibly affected by it. It will be noticed that the animals affected were non-ruminants, while those not affected were ruminants. The probable explanation is that the ruminants, by thoroughly mixing the food with saliva and slowly digesting it, were enabled to neutralize the action of the poison and escape injury. The seeds probably contain the deleterious principle in a greater degree than any other part of the plant. It was a common experience that animals introduced from other localities suffered more than the native animals. The latter were either immune or had learnt to avoid the plant as noxious to them."
That animals resident in a district are not poisoned by plants which are often fatal to sheep and cattle when on the march through it, has been often observed in Australia. The great "mobs" or droves of sheep passing slowly on their travels through the bush to a new district are often poisoned by the Caustic Creeper (Euphorbia Drummondi). "The head swells to an enormous extent, becoming so heavy that the animal cannot support it, and drags it along the ground"; but this does not apparently happen to resident cattle. Similarly for the Darling Pea or Indigo (Swainsonia galegifolia). At one place this was growing abundantly where some travelling horses were hobbled for the night. "They had been on the road some nine weeks, and were up to this date caught without any difficulty. On this occasion … their eyes were staring out of their heads, and they were prancing against trees and shrubs… When driven they would suddenly stop, turn round and round, and keep throwing their heads up as if they had been hit under the jaw… Two out of nine died, and five others had to be left at the camp."111
In other natural orders we find one or two dangerous plants amongst a whole series of perfectly harmless or useful forms. The Oleander, in the Olive order, Corncockle (Lychnis floscuculli), in the Pink order, Lactuca Scariola amongst Compositæ and others are all cases in point. So also is the Yew amongst Coniferæ, etc.
How do animals recognize these particular plants as being dangerous whilst all their allies are harmless? But the reader will answer that they do not; it is well known that animals are killed by eating poisonous plants, therefore poison cannot possibly be any protection against animals.
This is one of those interesting questions in which the suppression of apparently irrelevant details produces confusion.
As a matter of fact, wild animals, or even domesticated animals in nearly a wild state, do not eat the poisonous plants of the country in which they and their forefathers have been brought up – that is provided that they are either adult or are accompanied by full-grown animals. Almost every case of cattle-poisoning in Great Britain occurs when young calves, foals, or lambs are turned loose in the fields without any mature older head amongst them. Sometimes valuable stable-bred animals are lost, especially by eating yew-leaves, but there are exceedingly few instances of full-grown cattle being caught in such foolishness. When cattle, horses, or sheep are turned loose in a new country, plenty of cases do occur, and it is possible that they might make mistakes with unknown foreign plants which had escaped into their pastures here.
But almost every case of poisoning, even of cattle, shows that it is young cattle who foolishly eat foxgloves, dropwort, buttercup, etc., and occasionally die thereby.
Wild animals, who are of course brought up by their mothers, never seem to be poisoned. They probably recognize the dangerous plant by colour, smell, or taste. As a matter of fact, many are rendered conspicuous by some lurid sort of colour, such as bright red or purple. There is a general garishness of appearance about many of them. Aconite, Foxglove, Herb Paris, Henbane, and Nightshades all show this peculiar appearance. In Java it is said that the natives keep away wild pigs by planting hedges of certain species with purplish-red leaves around their plantations.
Perhaps the most interesting point of all is that it seems to be quite justifiable to conclude that animals do, somehow, manage to tell their offspring and each other what they should and should not eat.
Youth, with its tendency to rash experiment, is thus kept in check by the mature experience of age.
But it must be admitted that it is exceedingly difficult to arrive at the facts in any particular case.
I shall be rash enough to give an opinion as to the actual facts in connexion with the common Yew (Taxus baccata). The seeds are poisonous to poultry and pheasants, but the fleshy part round the seed is eaten with impunity by many wild birds (blackbirds, etc.). The leaves are sometimes poisonous and even fatal to horses, cattle, sheep, donkeys, and goats, but they are not eaten by or are harmless to roedeer. When, however, e.g., horses are killed by eating yew, it is generally found that they have been grazing on cut-off branches which have been left lying on the ground. In this condition probably some specially poisonous substance is developed in them.
As regards rabbits, it would be extremely comforting to believe that they would eat yew-leaves or anything else which would kill them, but, so far as one can judge, they can eat all sorts of things which ought to do so with perfect impunity.
