The large lakes Nyassa and Tanganika had been more or less explored, but the one possessing the greatest interest, the Victoria Nyanza--on account of the general impression that it was the head of the Nile--was almost wholly unknown. The persistence with which the Nile had mocked all previous attempts to find its source, had imparted a mystery to it and caused efforts to be made to unlock the secret, which were wholly disproportioned to its seeming value or real importance. This lake, therefore, was to be Stanley's first objective point. Livingstone, Speke and Burton, and others had seen it--_he_ would sail around it in a boat which he would take with him. This he had made in sections, so that it could be carried the nearly one thousand miles through the jungles of Africa to its destination. Everything being completed he started on his route, and in the latter part of 1874 found himself once more at Zanzibar, after an absence of four years. Here, in organizing his expedition, he discovered that the builder had made his boat, which he had christened the Lady Alice, a great deal heavier than he had ordered; but he luckily found a man in Zanzibar who was able to reduce its weight so that it could be transported by the carriers. His force consisted in all, of a little over three hundred men, and he took with him several powerful dogs. The interest of this great expedition begins where he struck off from the regular route of the caravans going west, and entered an entirely new country and encountered a new race of people. Instead of moving directly westward, he turned off to the north, and at length reached the western frontier of Ugogo, on the last day of the year 1874. The country at this point stretched before him in one vast plain, which some of the natives said extended clear to Nyanza. He found that his course led him along the extremity of Whumba, which he was glad to know, as he thought his march would now be unmolested. Two days' march brought them to the borders of Usandawa, a country abounding in elephants. Here he turned to the north-west and entered Ukimbu or Uyonzi on its eastern extremity. The guides he had hired in Ugogo to take him as far as Iramba here deserted him. Hiring fresh ones, he continued two days in the same direction, when these deserted him also, and Stanley found himself one morning on the edge of a vast wilderness without a guide.