Put a small glass inside the larger glass bowl.

Then, pour baby oil into the bowl to cover some or most of the glass. The glass in the oil will become nearly invisible as you will see!

Now take the glass out and turn it upside down and get some air inside the glass. Put it back in the bowl so the air bubble stays in the glass. What do you see now?

Why, do you see baby oil? Good question...what do you think?