How to pour ketchup

Practical science.

Are you one of those people who taps at the bottom of an inverted ketchup bottle, waiting in frustration for the sauce to pour? I am speaking of traditional ketchup bottles, not squeeze tubes, wide-mouth jars, or bottles designed to stand on their heads. Have you ever wondered if there is a right way to do it – a way that works, and makes scientific sense?

Yes, folks, there is a right way to do it, and it does make sense.

(HT: Cynical-C.)