Nature's Teachings. John George Wood

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      This is the singular apparatus attached to the Violet Snail (Janthina communis), which is common enough in the Atlantic, and derives its name of Violet-shell from its beautiful colour. The chief interest, however, centres in the apparatus which is popularly called the “raft,” and which sustains the shell and eggs. It is made of a great number of air-vessels, affixed closely to each other, and by the curious property of bearing its cargo slung beneath it instead of being laid upon it.

      Beneath the raft are the eggs, or rather, the capsules which contain the eggs, and at one end is the beautiful violet shell itself. The floating power of the raft is really astonishing, and even in severe tempests, when it is broken away from the animal, the raft continues to float on the surface of the waves, bearing its cargo with it.

      On the opposite side of the illustration are two examples of rafts constructed so exactly on the same principle as that of the Violet Snail, that they both might have been borrowed from it.

      The upper is the kind of raft which has often been constructed by sailors when trying to escape from a sinking ship, or by soldiers when wishing to convey troops across a river, and having no regular “pontoons” at hand. It is made simply by lashing a number of empty casks to a flooring of beams and planks.

      The amount of weight which such a structure will support is really astonishing, as long as the casks remain whole, and to upset it is almost impossible. Even cannon can be taken across wide expanses of water in perfect safety, and there is hardly anything more awkward of conveyance than a cannon, with its own enormous and concentrated weight, and all the needful paraphernalia of limber, ammunition (which may not be wetted, and of immense weight), horses, and men.

      Yet even this heterogeneous mass of living and lifeless weight can be carried on the cask-raft, which is an exact imitation of the living raft of the Violet Snail.

      Beneath the cask-pontoon is to be seen a sketch of a very curious vessel which is in use on the Nile, and I rather think on the Ganges also, though I am not quite sure. It is formed in the following manner:—

      In both countries there are whole families who from generation to generation have lived in little villages up the river, and gained their living by making pottery, mostly of a simple though artistic form, the vessel having a rather long and slender neck, and a more or less globular body.

      When a man has made a sufficient number of these vessels, he lashes them together with their mouths uppermost, and then fixes upon them a simple platform of reeds. The papyrus was once largely used for this purpose, but it seems to be gradually abandoned.

      He thus forms a pontoon exactly similar in principle with the cask-pontoon which has just been described. Then, taking his place on his buoyant raft, he floats down the river until he comes to some populous town, takes his raft to pieces, sells the pots and reeds, and makes his way home again by land.

      WAR AND HUNTING

      CHAPTER I.

      THE PITFALL, THE CLUB, THE SWORD, THE SPEAR AND DAGGER

      THE two subjects which are here mentioned are practically one, the warfare being in the one case carried on against mankind, and in the other against the lower animals, the means employed being often the same in both cases.

      One of the simplest examples of this double use is afforded by the Pitfall, which is employed in almost every part of the world, and, although mostly used for hunting, still keeps its place in warfare.

      On the right hand of the accompanying illustration is shown a section of the Pitfall which is so commonly used in Africa for the capture of large game. It is, as may be seen, a conical hole, the bottom of which is armed with a pointed stake. Should a large animal fall into the pit, the shape of the sides forces it upon the stake, by which it is transfixed. Even elephants of the largest size often fall victims to this simple trap. It is only large enough to receive the fore-legs and chest, but that is quite sufficient to cause the death of the animal, the stake penetrating to the heart.

      Many a hunter has fallen into these traps, and found great difficulty in escaping, while some have not escaped at all. Indeed, in many parts of Southern Africa, when part of one tribe is about to visit another, the pitfalls are always unmasked, lest the intended guests should fall into them.

      Even without the spike, the elephant would scarcely be able to save itself, owing to its enormous weight, unless helped out by its comrades before the hunters came up. Indeed, many pitfalls are intentionally made for this purpose, and are of a different shape, i.e. about eight feet in length and four in breadth.

      In those which are made for the capture of the giraffe, the pit is very deep, and the place of the stake is occupied by a transverse wall, which prevents the feet of the captive from touching the ground, and keeps it suspended until the hunters can come and kill it at leisure.

      Even in Belgium and our own country the pitfall is in use. When the field-mice were devastating the districts about Liege some years ago, their ravages were effectually checked by pitfalls, in which they were caught by bushels, the pitfalls being simple holes some two feet deep, and made wider below than above.

      The late Mr. Waterton contrived to rid his garden of field-mice by pitfalls constructed on the same principle, though more permanent. Finding that the little animals made great havoc among his peas just as they were starting out of the ground, he buried between the rows a number of earthen pickle-jars, sinking them to the level of the ground. He then rubbed the inside of the neck with bacon, and left them. The mice stooped down to lick off the bacon, fell into the jars, and, the neck being narrow and the sides slippery, they could not get out again.

      On the left hand of the illustration is the section of a pitfall made by the well-known Ant-lion (Myrmeleo), of which there are several species. The history of this wonderful insect is so familiar to us that it need not be repeated at length. Suffice it to say that it digs conical pitfalls in loose sandy soil, and that it places itself at the bottom of the pit, securing the insect victims with its jaws just as the larger animals are secured by the stake of the human hunter.

      It makes no false cover, as does the human hunter, but it always chooses soil so loose that if an insect approach the edge, the sand gives way, and it goes sliding down into the pit, whence its chance of escape is very small, even were there no deadly jaws at the bottom ready to receive it.

The Club

      The simplest of all offensive weapons is necessarily the Club. At first, this was but a simple stick, such СКАЧАТЬ