Breeze is a japanese maple made to react to the movement of passers-by. Owing to a shape-memory alloy and hidden electronic wiring, its branches rise and positions themselves towards the visitor in lightly undulating waves. Responding slowly or rapidly, the tree can have a brutal or gentle reaction. This human size weeping willow feels strangely inhabitted. Jill Coffin and John Taylor are winners of the BBI 2006 creation contest. At the same time as Breeze, the two American engineers are giving a conference on « nitinol » which was invented in the United States in 1962. Once twisted, and after being heated, this material can spring back to its initial shape with considerable force. Its uses are many: we can find nitinol in robotics, in deep-space probes, implants and many surgical tools.