air bubbles will support the sand which is now at the top after being inverted. the sand is fine enough to trickle through the bubbles onto the bottom layer, and will start to form a new pattern. the white sand is lighter than the black, and thus when the sand settles it will form nice streaks of black and white. the bubbles will try to move upwards, while the sand tries to move downwards, thus sand will constantly be allowed the flow through the bubbles. as to where the sand can trickle through its totally random, thus new patterns are always formed. its pretty interesting considering that its on my desk, and whenever i have nothing to do i will just invert it and see the trickling of sand, slowly forming a new pattern of black and white..

our life is never so clear cut that black and white are separate, they mingle and mix with each other. as a result interesting patterns can result, and that is what makes life beautiful. yin zhong yi tian yang yang zhong yi tian ying.. its what maintains balance in life.