FIRE is associated with strength and life-force. It is seen as highly purifying and protective, consuming impurities and driving back the darkness. In alchemy its symbol is an upward-pointing triangle.
WATER is the element of emotion and the unconscious. It has a physical existence, which can interact with all of the physical senses. Its alchemical symbol is a downward-pointing triangle.
AIR is warm and moist suspended in time and space, caught between the the above and the below. The alchemical symbol for air is an upward-pointing triangle, bisected by a horizontal line.
EARTH is grounding, the element of stability and stillness. It's alchemical symbol is a downward-pointing triangle, bisected by a horizontal line.