We learned about optical illusions today. As we were approaching the pond and nearby cranberry bog, we all thought we saw a small stream and waterfall. When we got to the clearing, there was no waterfall. When we went back up the trail to figure out what we saw, we realized that the moat surrounding the cranberry bog and the trickle of water coming out of a pipe made it look like a waterfall. Later, we looked up optical illusions.