We've all heard the old saw that Caesar's dying breath contained so many molecules that every breath we draw contains at least one of them. But human bodies produce other exhalations...
"Most human beings pass between 200 to 2,000 ml of gas per day in 13 to 14 flatus."
- http://www.k12.nf.ca/janecollins/teacher/outlines/science/gases/flatulence.htm
Caius Julius Caesar lived nearly 56 years, or approx. 20400 days (allowing for calendar errors, and rounded off to nearest 100). Assuming a 1000 ml/day level of flatulence (a cavalier assumption, since we know that the Roman diet was full of fart-enhancing stuff, such as beans and cabbages), that means Caesar passed a total of about 20400 liters, or 20.4 cubic meters of gas, in the course of his lifetime. Over 275000 farts, by the way. This is not an accurate figure, but it'll do until time travel comes along.
Now, as to Caesar's dying breath...
"The average pair of human lungs can hold about 6 liters of air, but only a small amount of this capacity is used during normal breathing."
- http://en.wikipedia.org/wiki/Lung_volumes
So, a breath is significantly less than 6 liters, yes? Still, it's a dying breath -- so let's just say, for the sake of argument, that Caesar expelled the full content of his lungs. You'd think he might have found breath for more than just an
"Et tu, Brute?", eh?
Anyway, that gives us an upper limit number to divide with, granting us this:
(Volume of Caesar's farts) / (Volume of Caesar's dying breath) > 3400.
Or, in other words: During his lifetime, Caesar produced farts measuring at least 3400 times the volume of his dying breath.
So, every time you draw in a breath, think of how you are inhaling history. Both ends of history.