It was a hazardous enterprise to which Livingstone and his fellow travellers were committed, and, humanly speaking, its success depended wholly on the discovery of water at periodical intervals. The “caravan” was a considerable one. Eighty cattle and twenty horses were not deemed too many for the waggons and for riding; these had to be watered, and the twenty men besides. Progress was necessarily slow. None could face the burning heat of the mid-day hours. They had to move forward in the mornings and the evenings. The waggon-wheels sank deep into the soft, hot sand; and the poor oxen dragging them laboriously forward were, at a critical time, nearly four days without water, “and their masters scarcely better off.” Aided, however, by the experience and keen instinct of the natives, they found wells in unsuspected places, and eventually made the banks of the Zouga River. After that, progress was easy. Leaving the waggons and oxen, they took to canoes, or wended their way along the riverbanks, until, on the morning of August 1st, they found themselves gazing on the waters of Lake Ngami, the first white people to see it so far as they knew. It had been one of the principal arguments with Livingstone for the journey that he would meet the famous chief Sebituane, who had saved the life of Sechele in his infancy, and who was renowned as a warrior and as a powerful and intelligent ruler. It meant another two hundred miles of travel to the north, and the jealousies of the chiefs, and their real or assumed fears for Livingstone’s safety, prevented the realisation of his hopes on this journey. There was nothing for it but to go back to Kolobeng, where the drought persisted as absolute as ever. Livingstone’s congregation and Mrs. Livingstone’s school had disappeared in search of better watered lands. It was clear that for Livingstone there was here “no abiding city.” He resolved to transport his wife and three children to the north. He made more of an eastward circuit this time, and Sechele accompanied them to the fords of the Zouga. Mrs. Livingstone was the first white lady to see Lake Ngami; but the purposed visit to Sebituane had again to be deferred. Livingstone’s aid was invoked for a fever-stricken party of Englishmen who were hunting ivory. One was already dead, but the others recovered under his treatment. His own children, however, sickened; and the party precipitately retired to “the pure air of the desert,” and so home to Kolobeng where another child was born to them, only to be carried away by an epidemic. “Hers is the first grave in all that country,” writes the bereaved father, “marked as the resting-place of one of whom it is believed and confessed that she shall live again.”