In addition, Thoreau notices circular heaps of stones about six feet in diameter that sit on the pond bottom. He wonders if they were formed on the ice by Indians and fell to the bottom in the spring, but decides that they are too regular and new for that. They can't be leech holes, as there are none in Walden. When water is quiet it is as glass. The fish and bugs make concentric circles on its surface that are beautiful.
Water is the intermediate form between earth and sky.
Unlike the earth, it is affected by the wind and ripples with it. And, we can look down upon it and examine it. Thoreau imagines having that opportunity with the air one day, but for now he can observe the water. When the water reflects the clouds, Thoreau imagines that he's floating through the air - and the fish look like they're hovering in air. There is an old man who visits Thoreau who found a log canoe years ago, when the pond was full of waterfowl, which it no longer is.