'Every time you breathe, you exhale 25 sextillion molecules of oxygen - so many that with a day's breathing you will in all likelihood inhale at least one molecule from the breaths of every person who has ever lived. And everyone who lives from now until the sun burns out will from time to time breathe a bit of you.'
Bill Bryson - The Body A Guide for Occupants
Bill Bryson - The Body A Guide for Occupants