Revelation

"I've been reading about rain, said Jean. That utterly distinctive smell, when rain first starts to fall - two scicentists have analyzed it. They named it 'petrichor' from the Greek for stone and for the 'blood' that flows through the veins of the gods. It's the scent of an oil produced by plants partially decomposed, undergoing oxidation and nitration, a combination of three compounds. The first raindrops reach into stone or pavement and release this plant oil, which we smell as it is washed away. We can only smell it as it is washed away."
Quoted from Teza's Garden blog