I was going across the singing river bridge in Florence AL around 4:30-4:40 pm. I can see the other side of the river from the bridge and there is a gray, object hovering in the sky along the line of trees. It's probably the size of a small aircraft. It swings from side to side for a few seconds, dips into the trees for maybe 4 seconds and the comes back up to the tree line and darts away toward the south east near the Wilson Dam. I could not see it anymore after it disappeared around the hills by the dam.