pasilalinic-sympathetic compass

The pasilalinic-sympathetic compass, also referred to as the snail telegraph, was a contraption built to prove the belief that snails create a permanent telepathic link when they touch. The belief was developed by French occultist Jacques Toussaint Benoit and colleague Monsieur Biat-Chretien in the early to mid 19th century. The telepathic bond was theorised to have no physical limit, with communication being possible over any distance. By touching one half of the snail partnership the other will sense the contact and will itself move. Benoit built apparatus to test his theories but it quickly became apparent that what he expected to be a communication revolution was just a costly failure.
See more at Wikipedia.org...