In the cemetery, a snake biting or eating its tail (known as the Ouroboros or Uroborus) is a symbol of immortality, rejuvenation, and eternity. It is seldom used in funerary art nowadays, but it was a very popular symbol in 19th-century cemeteries. Images of the Ouroboros can be found in the art of ancient Egypt (where it symbolized the daily cycle of the sun), China (where it was among the myriad yin and yang symbols), the Roman Empire (where it was associated with Saturn, the god of time), as well as in European and American funerary art. Beyond symbolizing immortality the ouroboros suggests that for every ending there is a new beginning. In alchemy, the ouroboros symbolizes a closed cyclical process (heating/evaporation/cooling/condensation), which refines or purifies substances