"His next sensation was that of being on the back of a pony which was led by one of his men. He angrily inquired why they were not following the track of the beast; but hardly had he spoken before he discovered that his hand, which had been resting on his side, was full of clotted blood, and he met his men, who had come from camp to bury him. He didn't need burying just then, but the wound required some time to heal, and he carried the scar for the rest of his life. [Illustration: RHINOCEROS HEADS.] "When Anderson killed his first rhinoceros he was wild with delight. Immediately on approaching his prostrate game he plunged his knife into its back, to ascertain if it was fat. The natives warned him not to repeat the experiment, as a short time before a native had done the same thing and got into serious trouble. The rhinoceros had been stunned instead of killed. The stroke of the knife revived him, and he rose and ran toward the river, with the unfortunate native clinging to his back. "The situation was anything but pleasant for the man, who dared not spring to the ground, for fear of being transfixed by the brute's horn, and ran the risk of being drowned if he stayed where he was till the river was reached. Happily the rhinoceros paused long enough to allow somebody else to send a shot that settled him and released the native from his free but involuntary ride." "His case reminds me," said Fred, "of a question I once heard proposed for a debating society in the country." "What is that?" said Frank. "'If a man is holding a tiger by the tail, which is the best for his personal safety--to hold on or let go?'" "A good deal might be said on both sides of that question," the Doctor remarked, "but perhaps the tiger would not permit a prolonged discussion. In one way the native on the rhinoceros had the advantage of the tiger man." "How was that?" "Why, the tiger might devour his caudal retainer, while the rhinoceros would not do so with his rider. He is strictly graminivorous, and never touches flesh to eat it. He devours grass, young trees, and similar things, and in this respect has quite a resemblance to the hippopotamus, whose cousin he is sometimes called." One of the boys asked if it was really true that the hide of the rhinoceros was impervious to bullets, except in a few places. The Doctor explained that an ordinary musket-ball, fired at a distance of fifty yards and more, had no effect, and even a rifle-ball might be deflected from most parts of this tough-hided beast. "It is no use to fire at the head with anything less than a cannon," he continued. "The only vulnerable point is about three inches behind the shoulder, and when a bullet is planted there at the proper angle it penetrates the lungs and causes death almost instantaneously.