Nature's Teachings: Human Invention Anticipated by Nature. J. G. Wood

Nature's Teachings: Human Invention Anticipated by Nature - J. G. Wood


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only about ten inches in length, very much larger arrows are used both for war and hunting, and are propelled by the bow, and not with the breath. Many of these arrows are nearly six feet in length. In all, the head is movable fitting quite loosely into a socket, so that when an animal is struck and springs forward, the shaft is shaken off, to be picked up by the hunter, and fitted with another point, while the poisoned head remains in the wound.

      Another kind of poison, also of a vegetable origin, is used by the Fan tribe. The arrows are mere little slips of bamboo, and are propelled by a slight crossbow. But the poison is so potent, that even these tiny weapons produce a fatal effect.

      Nearly in the centre of the illustration is seen a rather curiously formed syringe, with an extremely long and slender tip. This is a recently invented instrument, used for the purpose of subcutaneous injection—i.e. of injecting any liquid under the skin. It is mostly employed for injecting opium and other drugs of similar qualities, for the purpose of obtaining relief from local pain. The slender spike-like point is hollow, and ends in a sharp tip, formed like the head of a lance. Just below the head there is a little hole, communicating with the interior of the tube.

      The mode of operating is simple enough. The syringe is filled with the drug, and the point introduced under the skin at any given spot. Pressure on the piston then forces out the liquid, and causes it to mix with the blood.

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      Now, both in the animal and vegetable worlds may be found several examples of an apparatus which acts in exactly the same manner.

      The first is the poison-fang of the Serpent, a specimen of which is given on the left hand of the illustration. This fang answers in every respect to the syringe above mentioned. The long and slender fang is hollow, and answers to the pipe of the syringe. It communicates at the base with a reservoir of liquid poison, which answers to the body of the syringe, and there is a little hole, or rather slit, just above the point, which allows the poison to escape.

      When the serpent makes its stroke, the base of the fang is driven against the reservoir, so that the liquid is urged through the hollow tube, and forced into the wound. Even in large serpents these fangs are very small. I have now before me some fangs of the cobra, puff-adder, rattlesnake, and viper, and it is astonishing how small and slender are these most deadly weapons. The figure in the illustration is much magnified, in order to show the aperture at the base, where communication is made with the interior of the fang. As the exit hole is on the upper curve of the fang, it is not visible in the figure.

      Next to the serpent’s fang is a representation of the Bee-sting, the poisonous reservoir being seen at the base, and having attached to it the tiny thread-like gland by which the poison is secreted.

      In the centre is seen the tail of a Scorpion, with its hooked sting. The last joint is formed just like the serpent’s fang, being hollow, having a sharp point with a slit near the end, and a poison reservoir in the rounded base. When the scorpion attacks an enemy, it strikes violently with the tail, and the force of the blow drives out the poison just as is done with the serpent’s fang.

      At the bottom of the illustration is shown the poison-fang of a Spider, which, as the reader may see, is formed just on the principle of the scorpion-sting.

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      So much for animal poisons. We will now pass to the vegetable world.

      Of the vegetable sting-bearers none are more familiar to us than the Nettle, three species of which inhabit this country. The two commonest are the Great Nettle (Urtica diœcea) and the Small Nettle (Urtica urens), and both of them are armed with venomous stings, which cause the plants to be so much dreaded.

      The structure of these stings is very simple, and can be made out with an ordinary microscope, or even a good pocket lens. Each of these stings is, in fact, a rather elaborately constructed hair, hollow throughout its length, coming to a point at the tip, and having the base swollen into a receptacle containing the poisonous juice. When any object—such, for example, as the human hand—touches a nettle, the points of the stings slightly penetrate the skin, and the hair is pressed downwards against the base, so that the poison is forced through the hole.

      One of these hairs is shown in the left-hand bottom corner of the illustration.

      Even the tiny stings of our English nettles are sufficiently venomous to cause considerable pain, and, in some cases, even to affect the whole nervous system. But some of the exotic nettles are infinitely more formidable, and are, indeed, so dangerous that, when they are grown in a botanical garden, a fence is placed round them, so as to prevent visitors even from touching a single leaf.

      The two most dreaded species are called Urtica heterophylla and Urtica crenulata. The former is thought to be the more dangerous of the two, and a good idea of its venomous qualities may be gathered from an account of an adventure with Urtica crenulata. The narrator is M. L. de la Tour.

      “One of the leaves slightly touched the first three fingers of my left hand; at the time I only perceived a slight pricking, to which I paid no attention. This was at seven in the morning. The pain continued to increase, and in an hour it became intolerable; it seemed as if some one were rubbing my fingers with a hot iron. Nevertheless, there was no remarkable appearance, neither swelling, nor pustules, nor inflammation.

      “The pain spread rapidly along the arm as far as the armpit. I was then seized with frequent sneezing, and with a copious running at the nose, as if I had caught a violent cold in the head. About noon I experienced a painful attack of cramp at the back of the jaws, which made me fear an attack of tetanus. I then went to bed, hoping that repose would alleviate my suffering, but it did not abate. On the contrary, it continued nearly the whole of the following night; but I lost the contraction of the jaws about seven in the evening.

      “The next morning the pain began to leave me, and I fell asleep. I continued to suffer for two days, and the pain returned in full force when I put my hand into water. I did not finally lose it for nine days.”

      There is another of these formidable nettles, called in the East by a name which signifies “Devil’s Leaf,” and which is sufficiently venomous to cause death. There is but little doubt, however, that in the present instance, if a larger portion of the body—say the whole arm—instead of three fingers, had been stung, death would have ensued from the injury.

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      We now come to another improvement, or rather addition, in the various piercing weapons. Sometimes, as in the case of the dagger or the hand-spear, it was necessary that when a blow had been struck the weapon should be easily withdrawn from the wound, so as not to disarm the assailant, and to enable him to repeat the stroke if needful. But in the case of a missile weapon, such as a javelin or an arrow, it was often useful, both in war and hunting, to form the head in such a way that when it had once entered it could scarcely be withdrawn. For this purpose the Barb was invented, taking different forms, according to the object of the weapon and the nationality of the maker.

      As in this work I prefer to show the gradual development of human inventions, I shall take my examples of barbs entirely from the weapons of uncivilised nations, six examples of which are given in the accompanying illustration, and five of them being drawn from specimens in my collection.

      Image unavailable: BARBED WEAPONS. BARBED WEAPONS.

      The upper left-hand figure is


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