Creating a delightful dance of rising and falling mechanical “butterflies,” Butterfly Wall by Charles Sowers is an interactive kinetic sculpture controlled by ten visitor-operated hand-cranks. When cranked, the 20 butterflies continuously descend their belts at a rate dictated by the air resistance of their spinning iridescent wings. Cranking faster than the descent rate of the butterflies causes them to rise towards the ceiling; cranking slower than this rate causes the butterflies to flutter back down or hover in one place. This video was posted on January 28, 2017.