“Somebody came to me recently and said they wanted a fragrance that smelled like a rainbow mango,” [perfumer Stephen] Nilsen says. “I was like, I don’t know what that is. So I came in here and said, What might be there? Ethyl butyrate, some citrals, some green notes—a green apple, a little pear. Some peach.” He taps these notes and more into Carto, and the mechanism swings into action, measuring the ingredients into a sample vial. Nilsen removes the result as though from a vending machine and hands it to me to sniff. It smells like mango but brighter, zestier and more complex. A mango I might even want to wear on my skin.

— Red more in How chemists engineer the signature smells of luxury perfumes at Scientific American via Yahoo.