Cal and Rob were getting a good deal waked up on the river-horse question, and their mother dropped her book in her lap, although she had heard that story once or twice before. "Now, boys," she said, "don't interrupt your uncle. Let him tell it all his own way." Cal and Rob looked at each other. Cal had at least three questions in his mouth, and Bob had two, all ready to ask, but they shut their lips hard, and Rob took a tight grip of his chair, so he shouldn't let go of those questions. Uncle Marbury leaned back in his Sleepy Hollow chair, and went right on: "The black men go for them in boats, with harpoons that they make themselves. They take a stout pole, of a hard, heavy wood that grows there, and cut it to about ten or twelve feet long and three or four inches thick. That's the shaft of the harpoon. The head is made of a tough piece of iron, thicker than my finger, and about a foot long. It has a barbed spear-head at the end, and when those barbs get under the tough hide of a hippopotamus, all the plunging and struggling he can do won't make them pull out. "They bore a hole in the end of the pole just big enough to take in a few inches of the iron foot of the barbed head, and it fits loosely, so it'll come out. That's just what they want it to do. I'll tell you why. Just as soon as a hippopotamus is wounded, he turns to bite at the thing that hurt him, and if his great jaws and sharp teeth shut down on a piece of wood, they'd grind it to splinters, no matter how hard and strong it might be. If it was a rope, they'd cut it right off, and the hunters would lose their harpoon and their game too. So they leave the iron head loose, to come out, and fasten it to the pole by a sort of long band that is made of ever so many tough strong cords, not very large, any one of them, and these slip around among the teeth, and if some of them do get cut off, there are always enough left to hold by. "The other end of the pole has a long rope, like a whale line, tied to it, and that is coiled up in the boat, and they let it run out or pull it in, just as they see fit. "We had two of those harpoons in each of our boats, and all of the black men had spears, and Lloyd and I had double-barrelled rifles, and our first river-horse was almost too much for us in spite of them all." "Did he fight hard?" "Calvin!" said his mother. "I'll tell you. Lloyd and I had a good yawl boat we had brought with us, and half a dozen black men to paddle, and there were two canoes, each with three black men in it, but we didn't bring any canoes home. Mr. Lloyd and I and my black servant were the only men in those boats that had any clothes on to speak of.