When a breeze brushes through the field just below Vollis Simpson's machine shop, you can hear the sounds of metal clanging against metal and of Ferris wheel-like contraptions turning.

But the cacophony of sound from the 29 whirligigs that Simpson built over a period of 10 years has ebbed: The buggy rider's whip no longer moves, the horse's legs don't trot and his ears don't flap. The two men sawing on another whirligig don't move back and forth. The guitar player no longer strums and has slowed the pat of his foot. Tree limbs grow through a Ferris wheel lined inside with hundreds of stainless steel milkshake cups that still shimmer in the sun despite their decades of exposure.