with dense matted vegetation at the narrower parts, the lake again began to subside, falling over 10 feet by 1882, and 5 feet more by 1886. This subsidence caused great alarm to the natives, who feared the "white wizards" might empty the whole lake by throwing "medicines" into Lu-Kuga. "See," said a chief to M. Giraud, "how they cross the lake and the water goes with them." Their
ignorance of any former outflow seems to show that the basin was long closed before its recent rise to the level of Lu-Kuga.
According to the latest measurements, Tanganyika stands over 2,600 feet above the sea, which would give the emissary a fall of about 7 feet per mile, during its course of 120 miles to the Congo. Throughout its upper course, which alone has hitherto been surveyed, the current is very rapid, without, however, forming any cascades. Its foaming waters flow through a charming valley between wooded hills, rising on both sides from 800 to 2,000 feet above the
