When ringmaster Birk pulls out a battered chess piece with a strand of copper wire protruding from the top, it becomes instantly clear to his amazed audience that his troupe of stunt-pulling acrobats, chariot racers and goal scorers are not mere virtual characters or part of some digitally mastered electronic "experience".
A hearing loop, typically installed on the floor around the periphery of a room, is a thin strand of copper wire radiating electromagnetic signals that can be picked up by a tiny receiver already built into most hearing aids and cochlear implants.
But it takes a lot of delicate adjustment to overlay a torrent of data on top of a trickle of voice on a mile-long strand of copper.
Still more coordination is required to take care of interference between lines, because the clamor from data pouring down one strand of copper can interfere with traffic in adjacent strands that lead to other homes.
Repeat this for the other strand of copper wire and the other end of the battery.
Investigators studying the failed conductors realized that part of the problem lay in the fact that in the Japanese sample each triplet was made up of two niobium-tin strands and one of copper.
Take one strand of the copper wire not in the glass jar and wrap the end around one end of the battery.
The portrait of President Kennedy by Bruce Greenwood is a startling realization; he poses to look like him, right down to the carefully choreographed strands of chestnut and copper hair on his long-suffering head.
(The foundation is giving about two dozen artworks to the Whitney, including Los Angeles photos by Ed Ruscha, and Bertoia bundles of copper strands).
Not a strand of her copper-colored hair was out of place.
