Petrichor
I’m not too sure about the word petrichor, invented in 1964 as a label for the pleasant smell frequently accompanying the first rain after a long period of warm, dry weather. Some things about it are awkward. Two Australians, Richard Thomas and Joy Bear, had been working for the Commonwealth Scientific and Industrial Research Organisation on the chemistry behind the smell. They found it comes from the ‘blue haze’ of hot summer days, part of the 450 million tons of volatile compounds released by plants into the atmosphere each year. But in the air the compounds do not smell attractive, as they do after being catalysed on the surfaces of