Fiery Water

From Wikipedia entry “Fire (classical element)” uploaded by Bryan Derksen

 In alchemy the triangle that points up is the symbol of fire while the triangle that points down is the symbol of water 

From Wikipedia entry “water (classical element)” uploaded by Bryan Derksen

Fire and water (needless to say) are opposites. In the hexagram they interpenetrate and together they represent the unity of the opposites or (in alchemy)- the fiery water -that’s why hexagrams were drawn on the signs above shops that sold brandy until about hundred years ago. 

Plinius explained the word "pyramid" as coming from the Greek root PYR (Fire). Pyramid is comprised from triangles pointing up to the sun.