The primal elements of sulphur (that which burns) and mercury (that which is volatile) are embodied in the androgyne or hermaphrodite. The union of these opposite principles is the purpose of alchemy and of human endeavour itself. The androgyne wears the crown of perfection. It stands on a dragon - a serpent with bird's feet - symbolizing its dominion over the forces of land, sea and air. The four heads of the dragon represent the four elements - fire, air, water and earth.