The DuLuc Dry Pile
High-voltage source
©1996 William J. Beaty

I have a friend who runs a diecutting printshop who might be able to turn out the disks in large quantities. I suspect that zinc foil is hard to find, but probably is not required. Perhaps aluminized paper and copper foil, or even silver leaf paper can be obtained, then simply punched out and stacked up. Or perhaps carbon paper can act as both electrolyte and electrode, using aluminum foil as the second electrode on each disk.

A 5ft dry pile should raise the hair of anyone who touches the end. Or a shorter one could act as a "magic wand": hold one end, touch someone's body with the other to charge them up, then touch their nose with your finger. SNAP!

A book on the history of Perpetual Motion Machines showed photos of "genuine" perpetual motion devices based on the Dry Pile. DuLuc's version was composed of two series-connected Dry Piles operating a pendulum electrostatic motor of the "Franklin's Bell" type. The drypile stacks were of the 3-glass-rod variety, and had been insulated by dipping in liquid sulfur (no plastics in 1806!) The device in the book is owned by Dr. A.J. Croft of Oxford's Clarendon Lab. At the time of publication of the book, this device had been tinkling away for over a century, and the owner of the device mentioned that the clapper-bead was starting to take on a distinct hourglass shape, and may need to be replaced in the next few centuries! A second device by Zamboni was a perpetually rotating "Franklin's wheel" electrostatic motor powered by two dry piles. Zamboni experimented with drypile-powered clocks in the early 1800s.

Dry piles found commercial use as the power supplies of electrostatic voltmeters (quadrant electrometers), and in infrared converter "night vision" scopes used in World War II.