Nothing that Livingstone and Stanley did, helped to solve the mystery of an outlet, except their discovery of the Rusizi, at the north, which was an inlet. After a three weeks cruise they returned to Ujiji, whence Stanley started back for Zanzibar, accompanied part way by Livingstone. After many days’ journey they came to Unyanyembe where they parted forever, Stanley to hasten to Zanzibar and Livingstone to return to the wilds to settle finally the Nile secret. Stanley protested, owing to the doctor’s physical condition. But the enthusiasm of travel and research was upon him to the extent that he would not hear. Stanley had left ample supplies at Unyanyembe. These he divided with the doctor, so that he was well off in this respect. He further promised to hire a band of porters for him at Zanzibar and send them to him in the interior. They parted on March 13, 1872. “God guide you home safe, and bless you, my friend,” were the doctor’s words. “And may God bring you safe back to us all, my dear friend! Farewell!” “Farewell!” This was the last word Doctor Livingstone ever spoke to a white man. They wrung each other’s hands. Stanley was overcome, and turned away. He cried to his men, “Forward March!” and the sad scene closed. Livingstone waited at Unyanyembe for the escort Stanley had promised to send. They came by August, and on the 14 of the month (1872) he started for the southern point of Tanganyika, which he rounded, to find no outlet there. Then he struck for Lake Bangweolo, intending to solve all its river mysteries. That lake was to him an ultimate reservoir for all waters flowing north, and if the Lualaba should prove to be the Nile, then he felt he had its true source. This journey was a horrible one in every respect. It rained almost incessantly. The path was miry and amid dripping grass and cane. The country was flat and the rivers all swollen. It was impossible to tell river from marsh. The country was not inhabited. Food grew scarce. The doctor became so weak that he had to be carried across the rivers on the back of his trusty servant Susi. One stream, crossed on January 24, 1873, was 2000 feet wide and so deep that the waters reached Susi’s mouth, and the doctor got as wet as his carrier. These were the dark, dismal surroundings of Lake Bangweolo. Amid such hardships they skirted the northern side of the lake, crossed the Chambesi at its eastern end, where the river is 300 yards wide and 18 feet deep, and turned their faces westward along the south side. The doctor was now able to walk no further. When he tried to climb on his donkey he fell to the ground from sheer weakness. His faithful servants took him on their shoulders, or bore him along in a rudely constructed litter. On April 27, 1873, his last entry reads, “Knocked up quite, and remain——recover——sent to buy milch goats. We are on banks of the R. Molilamo.” [Illustration: THE STREAM CAME UP TO SUSI’S MOUTH.]