In 1866 Livingstone resumed his explorations of East-Central Africa. He travelled overland south-westwards from the Ruvuma River to the south end of Lake Nyasa, then north-west and north to the south end of Tanganyika, thence from Tanganyika to Lake Mweru, to the mighty Luapula River, and to Bangweulu, which lakes and river he discovered in 1868. Again reaching Tanganyika, he joined some Arabs and crossed the Manyema country eastward to Nyangwe, on the Lualaba-Congo. From here he returned to Ujiji, where he was met by Mr H. M. Stanley, who had been sent out by the _New York Herald_ to relieve the great explorer. After travelling with Stanley half-way back to Zanzibar, Livingstone returned to Lake Bangweulu, and died there in 1873. Various expeditions had been despatched to his relief. One under Lieutenant Grandy was sent out in 1873 to ascend the Congo, but the expedition was most unfortunate, and the explorer died near São Salvador[180]. After many changes and withdrawals, a great expedition, organized by the Royal Geographical Society, started from Zanzibar in 1873 to find and relieve Livingstone. It was under the leadership of Lieutenant (afterwards Commander) Verney Lovett Cameron. Cameron soon heard of Livingstone’s death, but pushed on to Tanganyika, and mapped that lake for the first time accurately. He then travelled across to the Lualaba, which his altitudes practically determined to be none other than the Upper Congo; but, deterred from descending it by the tremendous difficulties that offered themselves, he struck south-westwards across a country not very difficult to traverse—the slightly civilized Mwata Yanvo’s empire (impregnated with Portuguese influence), and reached Benguela in November 1875, the first Englishman to cross Africa.