The next morning we followed the eastern branch, and passing many steep hills, crossed a pass 5,500 ft. high, and again descended into the main valley. Numerous small streams intersected the hills, and at each ford clouds of gorgeous butterflies enlivened the scene, attracted apparently by the moisture. On the way we crossed many fresh tracks of elephant, and on the western slope of the valley a large herd had followed the track in the early morning. At the base of the slope we had much difficulty in fording a deep and rapid river, called the Kasilo; several goats and a calf were washed away, and the rest were only saved by the brilliant swimming of the Watonga contingent. Thence two hours’ hard travelling brought us to the second German Soudanese fort, situated on a small hill overlooking the Rusisi, where it issues from its broken course through the mountains which dam the south end of Lake Kivu, preparatory to its seventy-five-mile run through the flat valley bed to Lake Tanganyika. The Soudanese officer in command was most courteous and personally presented all the local potentates, who brought us supplies of bananas, flour, and goats. He also promised to try and trace my lost elephant, but said that if, as was most probable, it had crossed the river it would be impossible to recover ivory from the obstreperous chiefs in the Congo Free State. Here, as during the whole of our journey from Tanganyika, the mosquitoes were appalling; colossal of stature, they arrived in myriads at sunset, and continued their plaintive wail till the cool hour before dawn. On the morrow we left the Rusisi once more, and passed to the east of many striking conical hills along the flat plain of the Kasilo (which obviously in remote ages was the course of the outlet of Lake Kivu), for a distance of four miles, crossing several small tributaries of the Kasilo on our way. We turned west, and climbing the high plateau through which the Rusisi has now forced its way, camped on a high ridge 2,000 ft. above the plain. There were numerous villages and large herds of cattle, which at night are enclosed in pens strongly stockaded. Here we had entered the terrible Ruanda country, and the paramount chief of the district, Ngenzi, the most powerful satrap of the King of Ruanda, came and paid his respects. From his pleasant manner we little guessed what a source of trouble he was to prove in the near future. Small boys followed us on the march with huge wooden utensils filled with fresh milk, and our welcome was most cordial. Forests of bananas stretched far as the eye could reach to the north, east, and west, and vast fields of peas and beans bore witness to the fertility and prosperity of the country. To the south lay the mighty valley of the Rusisi, stretching away between its enclosing walls of hills, till, in the far distance, gleamed the waters of Tanganyika.