How does a sand picture work?

A sand picture consists of two panes of glass glued together, the space between panes is filled with three kinds of coloured sand and liquid. These air tight panes are embedded in plastic, wooden or aluminium frames. In order to obtain the desired effect a certain amount of air needs to 'support' the sand. Sand grains squeeze themselves through air bubbles and create fantastic, unique compositions when they fall.

When the whole amount of sand has trickled and you are not happy with the final result, just turn the sandpicture over to create a new, unique composition. Below you can see how to use a sandpicture in order to obtain desired effects.

This is an example of a HTML caption with a link.