Uroboros, The Snake that bites in its own tail.
There are a number of interpretations about the logic or values behind the Uroboros snake (also called Ouroboros and Uroborus). The normal explanation: it symbolizes the recycling or renewal of the Universe.

In Uroborus an endless feedback loop is created by wiring a reversing switch (dpst) to a reversible DC motor that mechanically activates the switch.

“It’s one of my favorites,” says Peter Richards. “It looks homemade, yet it’s elegant. It’s humorous. : And it connects to a powerful cultural symbolism. “Exhibits We Love and Why : News From The Exploratorium,” Sept.-Oct. 2003, page 3.