That earthy smell that permeates through the damp air after a rainy night as you leave your garden or walk through the park; that’s petrichor. It stems from the Greek word ‘petra’, simply meaning stone, and the suffix ‘ichor’, the ethereal fluid that ran through the veins of the gods revered by said stone-describing people. After being investigated in 1964, it was revealed that this olfactory phenomenon is due to an oil exuded by certain plants during dry spells along with geosmin, an organic compound produced by soil-dwelling bacteria being taken up into the air when it rains.
