On a white butcher's scale there is a small video monitor
which reproduces the image of the scale with two human hands alternatively
pressing it with one finger. Every time one of the virtual fingers presses
the virtual scale, the physical scale is activated. The spectator realizes
this at the sound produced by the physical scale in motion and by the
movement of the "dial" - a cylinder indicating the weight, which
can be read on both sides, the butcher's and the customer's.