"I can't imagine," said Frank; "but anyway it seems as though your new process of cooking was not a brilliant success. You won't hold office as cook very long." "Not if the dinner is going to blow up in this way every time," was the reply. "But I'd like to know how it happened." "The explanation is very simple," said the Doctor, who had been called from his tent by the explosion. "The stones came from the lake, where they have been lying for centuries. They contained cells filled with water, and as the stones were heated the water was turned to steam. Hence the blow-up." Fred decided that he would make no farther experiments in teaching the uneducated African the mysteries of American cookery. Frank made a sketch of the scene, with a few exaggerations, and said he believed a similar incident was narrated in "Porte Crayon's" account of a journey in the mountains of North Carolina. [Illustration: ON THE LAKE.] CHAPTER XXVI. RIPON FALLS.--THE OUTLET OF THE VICTORIA N'YANZA. As they approached the northern end of the lake they passed a high hill, which was marked on the chart as "Jack's Mount." Referring to Stanley's account of his voyage around the lake, they ascertained that the hill received its name in honor of one of the four-footed companions of that explorer. [Illustration: JACK.] When Stanley left England he took, as members or _attachés_ of his expedition, five dogs, three of which died before he reached Ugunda. "Jack" and his companion, "Bull," were the survivors when they arrived near this mountain. A wild cow that had been given by one of the chiefs behaved so badly that Jack deemed it his duty to correct her; but she was not to be intimidated. In the struggle for control the unfortunate dog was gored to death. Stanley says: "He died regretted by all who had known his many good qualities. His companion, Bull, when he beheld his poor mate stretched out still and dead, also expressed, as clearly as canine nature would allow, his great sorrow at his lamentable fate. Grave and deliberate, from years and long travel, he walked round the body two or three times, examining it carefully, and then advanced to me, with his honest eyes wide open, as if to ask, 'What has caused this?' Receiving no answer, he went aside and sat down, with his back toward me, solemn and sad, as though he were ruminating despondingly on the evils which beset dog and man alike in this harsh and wicked world."