I’m not a scientist, but this question has always interested me, especially since I have often wondered why I don’t see air. I can see trees swaying, birds flying, planes overhead, and snow blowing, but I can’t see the actual air. Why not? When I look at the ocean, I see a clear line where the air stops and the water begins. When I am in water, I can see some things, but the water around makes it blurry.   One day, as I thought about the fish in the ocean and how things are b