Animated garden

I made this shape by slowly stretching a thin layer of clay into a circular form creating a nice rounded shape. Next I enclosed a pocket of air by covering it with another layer of clay to serve as the bottom and cut the circle through and through. When I cut the smaller circle, I must insert a blade along the edge to allow some air to escape and I seal it up afterwards. See "pre-cursor" to see how I achieved this effect.

Done