Spotty knew that Billy Mink was making fun of him, but he is too good-natured to lose his temper over a little thing like that. He tried to think of something smart to say in reply, but Spotty is a slow thinker as well as a slow walker, and before he could think of anything, Billy was talking once more. “This wall is what Farmer Brown's boy calls a dam,” said Billy Mink, who is a great traveler. “Dams are usually built to keep water from running where it isn't wanted or to make it go where it is wanted. Now, what I want to know is, who under the sun wants a pond way back here in the Green Forest, and what is it for? Who do you think built this dam, Grandfather Frog?” Grandfather Frog shook his head. His big goggly eyes seemed more goggly than ever, as he stared at the new pond in the Green Forest. “I don't know,” said Grandfather Frog. “I don't know what to think.” “Why, it must be Farmer Brown's boy or Farmer Brown himself,” said Jerry Muskrat. “Of course,” said Little Joe Otter, just as if he knew all about it. Still Grandfather Frog shook his head, as if he didn't agree. “I don't know,” said Grandfather Frog, “I don't know. It doesn't look so to me.” Billy Mink ran along the top of the dam and down the back side. He looked it all over with those sharp little eyes of his. “Grandfather Frog is right,” said he, when he came back. “It doesn't look like the work of Farmer Brown or Farmer Brown's boy. But if they didn't do it, who did? Who could have done it?” “I don't know,” said Grandfather Frog again, in a dreamy sort of voice. Spotty the Turtle looked at him, and saw that Grandfather Frog's face wore the far-away look that it always does when he tells a story of the days when the world was young. “I don't know,” he repeated, “but it looks to me very much like the work of--” Grandfather Frog stopped short off and turned to Jerry Muskrat. “Jerry Muskrat,” said he, so sharply that Jerry nearly lost his balance in his surprise, “has your big cousin come down from the North?” CHAPTER XVIII: Jerry Muskrat's Big Cousin Fiddle, faddle, feedle, fuddle! Was there ever such a muddle? Fuddle, feedle, faddle, fiddle! Who is there will solve the riddle? Here was the Laughing Brook laughing no longer. Here was the Smiling Pool smiling no longer. Here was a brand new pond deep in the Green Forest. Here was a wall of logs and bushes and mud called a dam, built by some one whom nobody had seen. And here was Grandfather Frog asking Jerry Muskrat if his big cousin had come down from the North, when Jerry didn't even know that he had a big cousin. “I--I haven't any big cousin,” said Jerry, when he had quite recovered from his surprise at Grandfather Frog's question. “Chugarum!” exclaimed Grandfather Frog, and the scornful way in which he said it made Jerry Muskrat feel very small. “Chugarum! Of course you've got a big cousin in the North. Do you mean to tell me that you don't know that, Jerry Muskrat?”