This is what happens when you subject mercury to different tones of sound. This would be an example of cymatics, which is the study of visible sound and vibration. The footage above is slow-motion, and set to music.
Nick Moore, the photographer explains:
The mercury is sitting in a concave plastic lens from an old projection TV (it was convenient), the lens is stuck to a 12inch speaker using Silly Putty to stop it from rattling around or bouncing.
The tone is a pure sine from an old signal generator (1960s) I believe it was between 10Hz and 120Hz. The higher the frequency the more nodes (bumps) appear on the mercury. They are actually 3 dimensional standing waves.
Here is the original video, at full speed, with the original tones that the mercury is reacting to: