The natives inhabiting the banks of the rivers falling into Lake Ngami are famed for their skill in hunting the hippopotamus. In perfect silence they approach in their light canoes, and plunge their sharp spears, with thongs attached, into the back of one of the huge creatures, which dashes down the stream, towing the canoe at a rapid rate. Thus the animal continues its course, the hunters holding on to the rope, till its strength is exhausted, when, other canoes coming up, it is speared to death. Frequently, however, the hippopotamus turns on its assailants, bites the canoe in two, and seizes one of them in its powerful jaws. When they can manage to do so, they tow it into shallow water, and, carrying the line on shore, secure it to a tree, while they attack the infuriated animal with their spears, till, sinking exhausted with its efforts, it becomes their prey. Mr Oswell, who had arrived too late for the journey, spent the remainder of the season in hunting elephants, liberally presenting Dr Livingstone with the proceeds of his sport, for the outfit of his children. The third journey was commenced in the spring of 1851, when, rejoined by Mr Oswell, he set out once more, accompanied by Mrs Livingstone and their children. First travelling north, and then to the north-east, through a region covered with baobab-trees, abounding with springs, and inhabited by Bushmen, they entered an arid and difficult country. Here, the supply of water being exhausted, great anxiety was felt for the children, who suffered greatly from thirst. At length a small stream, the Mababe, was reached, running into a marsh, across which they had to make their way. During the night they traversed a region infested by the _tsetse_, a fly not much larger than the common house-fly, the bite of which destroys cattle and horses. It is remarkable that neither man, wild animals, nor even calves as long as they continue to suck, suffer from the bite of this fearful pest. While some districts are infested by it, others in the immediate neighbourhood are free, and, as it does not bite at night, the only way the cattle of travellers can escape is by passing quickly through the infested district before the sun is up. Sometimes the natives lose the whole of their cattle by its attacks, and travellers frequently have been deprived of all means of moving with their wagons, in consequence of the death of their animals; some, indeed, have perished from being unable to proceed. Having reached the Chobe, a large river, which falls into the Zambesi, leaving their attendants encamped with their cattle on an island, Dr Livingstone and his family, with Mr Oswell, embarked in a canoe on the former river, and proceeded down it about twenty miles to an island, where Sebituane was waiting to receive them.