Missionary Travels and Researches in South Africa. David Livingstone

Чтение книги онлайн.

Читать онлайн книгу Missionary Travels and Researches in South Africa - David Livingstone страница 22

Автор:
Серия:
Издательство:
Missionary Travels and Researches in South Africa - David Livingstone

Скачать книгу

saw, was called Moroa Majane, or son of Majane, and proved an active guide across the River Sonta, and to the banks of the Chobe, in the country of Sebituane. We had come through another tsetse district by night, and at once passed our cattle over to the northern bank to preserve them from its ravages.

      A few remarks on the Tsetse, or 'Glossina morsitans', may here be appropriate. It is not much larger than the common house-fly, and is nearly of the same brown color as the common honey-bee; the after part of the body has three or four yellow bars across it; the wings project beyond this part considerably, and it is remarkably alert, avoiding most dexterously all attempts to capture it with the hand at common temperatures; in the cool of the mornings and evenings it is less agile. Its peculiar buzz when once heard can never be forgotten by the traveler whose means of locomotion are domestic animals; for it is well known that the bite of this poisonous insect is certain death to the ox, horse, and dog. In this journey, though we were not aware of any great number having at any time lighted on our cattle, we lost forty-three fine oxen by its bite. We watched the animals carefully, and believe that not a score of flies were ever upon them.

      A most remarkable feature in the bite of the tsetse is its perfect harmlessness in man and wild animals, and even calves, so long as they continue to suck the cows. We never experienced the slightest injury from them ourselves, personally, although we lived two months in their HABITAT, which was in this case as sharply defined as in many others, for the south bank of the Chobe was infested by them, and the northern bank, where our cattle were placed, only fifty yards distant, contained not a single specimen. This was the more remarkable, as we often saw natives carrying over raw meat to the opposite bank with many tsetse settled upon it.

      The poison does not seem to be injected by a sting, or by ova placed beneath the skin; for, when one is allowed to feed freely on the hand, it is seen to insert the middle prong of three portions, into which the proboscis divides, somewhat deeply into the true skin; it then draws it out a little way, and it assumes a crimson color as the mandibles come into brisk operation. The previously shrunken belly swells out, and, if left undisturbed, the fly quietly departs when it is full. A slight itching irritation follows, but not more than in the bite of a mosquito. In the ox this same bite produces no more immediate effects than in man. It does not startle him as the gad-fly does; but a few days afterward the following symptoms supervene: the eye and nose begin to run, the coat stares as if the animal were cold, a swelling appears under the jaw, and sometimes at the navel; and, though the animal continues to graze, emaciation commences, accompanied with a peculiar flaccidity of the muscles, and this proceeds unchecked until, perhaps months afterward, purging comes on, and the animal, no longer able to graze, perishes in a state of extreme exhaustion. Those which are in good condition often perish soon after the bite is inflicted with staggering and blindness, as if the brain were affected by it. Sudden changes of temperature produced by falls of rain seem to hasten the progress of the complaint; but, in general, the emaciation goes on uninterruptedly for months, and, do what we will, the poor animals perish miserably.

      When opened, the cellular tissue on the surface of the body beneath the skin is seen to be injected with air, as if a quantity of soap-bubbles were scattered over it, or a dishonest, awkward butcher had been trying to make it look fat. The fat is of a greenish-yellow color and of an oily consistence. All the muscles are flabby, and the heart often so soft that the fingers may be made to meet through it. The lungs and liver partake of the disease. The stomach and bowels are pale and empty, and the gall-bladder is distended with bile.

      These symptoms seem to indicate what is probably the case, a poison in the blood, the germ of which enters when the proboscis is inserted to draw blood. The poison-germ, contained in a bulb at the root of the proboscis, seems capable, although very minute in quantity, of reproducing itself, for the blood after death by tsetse is very small in quantity, and scarcely stains the hands in dissection. I shall have by-and-by to mention another insect, which by the same operation produces in the human subject both vomiting and purging.

      The mule, ass, and goat enjoy the same immunity from the tsetse as man and the game. Many large tribes on the Zambesi can keep no domestic animals except the goat, in consequence of the scourge existing in their country. Our children were frequently bitten, yet suffered no harm; and we saw around us numbers of zebras, buffaloes, pigs, pallahs and other antelopes, feeding quietly in the very habitat of the tsetse, yet as undisturbed by its bite as oxen are when they first receive the fatal poison. There is not so much difference in the natures of the horse and zebra, the buffalo and ox, the sheep and antelope, as to afford any satisfactory explanation of the phenomenon. Is a man not as much a domestic animal as a dog? The curious feature in the case, that dogs perish though fed on milk, whereas the calves escape so long as they continue sucking, made us imagine that the mischief might be produced by some plant in the locality, and not by tsetse; but Major Vardon, of the Madras Army, settled that point by riding a horse up to a small hill infested by the insect without allowing him time to graze, and, though he only remained long enough to take a view of the country and catch some specimens of tsetse on the animal, in ten days afterward the horse was dead.

      The well-known disgust which the tsetse shows to animal excreta, as exhibited when a village is placed in its habitat, has been observed and turned to account by some of the doctors. They mix droppings of animals, human milk, and some medicines together, and smear the animals that are about to pass through a tsetse district; but this, though it proves a preventive at the time, is not permanent. There is no cure yet known for the disease. A careless herdsman allowing a large number of cattle to wander into a tsetse district loses all except the calves; and Sebituane once lost nearly the entire cattle of his tribe, very many thousands, by unwittingly coming under its influence. Inoculation does not insure immunity, as animals which have been slightly bitten in one year may perish by a greater number of bites in the next; but it is probable that with the increase of guns the game will perish, as has happened in the south, and the tsetse, deprived of food, may become extinct simultaneously with the larger animals.

      The Makololo whom we met on the Chobe were delighted to see us; and as their chief Sebituane was about twenty miles down the river, Mr. Oswell and I proceeded in canoes to his temporary residence. He had come from the Barotse town of Naliele down to Sesheke as soon as he heard of white men being in search of him, and now came one hundred miles more to bid us welcome into his country. He was upon an island, with all his principal men around him, and engaged in singing when we arrived. It was more like church music than the sing-song ee ee ee, ae ae ae, of the Bechuanas of the south, and they continued the tune for some seconds after we approached. We informed him of the difficulties we had encountered, and how glad we were that they were all at an end by at last reaching his presence. He signified his own joy, and added, "Your cattle are all bitten by the tsetse, and will certainly die; but never mind, I have oxen, and will give you as many as you need." We, in our ignorance, then thought that as so few tsetse had bitten them no great mischief would follow. He then presented us with an ox and a jar of honey as food, and handed us over to the care of Mahale, who had headed the party to Kolobeng, and would now fain appropriate to himself the whole credit of our coming. Prepared skins of oxen, as soft as cloth, were given to cover us through the night; and, as nothing could be returned to this chief, Mahale became the owner of them. Long before it was day Sebituane came, and sitting down by the fire, which was lighted for our benefit behind the hedge where we lay, he narrated the difficulties he had himself experienced, when a young man, in crossing that same desert which we had mastered long afterward. As he has been most remarkable in his career, and was unquestionably the greatest man in all that country, a short sketch of his life may prove interesting to the reader.

      Sebituane was about forty-five years of age; of a tall and wiry form, an olive or coffee-and-milk color, and slightly bald; in manner cool and collected, and more frank in his answers than any other chief I ever met. He was the greatest warrior ever heard of beyond the colony; for, unlike Mosilikatse, Dingaan, and others, he always led his men into battle himself. When he saw the enemy, he felt the edge of his battle-axe, and said, "Aha! it is sharp, and whoever turns his back on the enemy will feel its edge." So fleet of foot was he, that all his people knew there was no escape for the coward, as any such would be cut

Скачать книгу