is a large interactive installation and an expansion of an earlier piece, MICRO. Two waves of touch interactive spheres create sound and light across the Marshall Way Bridge, over the Arizona Canal in Scottsdale, AZ. People are the bonds that bring the Double Helix to life. As people touch the spheres, each sphere replies with a different sound and light (each having it's own speaker, sound, and LED within). Commissioned by Scottsdale Public Art, for Canal Convergence 2016. A Purring Tiger collaboration.