PacSci-Doku: "Antique Experiment" Answer

By Dennis Schatz - Senior Vice President for Strategic Programs

The question in this edition is:

What experiment has been running continuously for 80 years?

The answer: Pitch Drop

Scroll down to see the solution.

Pitch -- made from tar and used in the past for waterproofing wooden boats -- appears to be a solid at room temperature. But an experiment started in 1930 proves that pitch is really a very thick liquid that flows at 100 billionth the rate of water. 1930 was when Dr. Thomas Parnell of the University of Queensland in Australia started watching pitch flow out of a large glass funnel. Since then, he and his colleagues have monitored the movement of the pitch as it flows out of the funnel's tip. Over 80 years, nine drops have dripped out of the funnel, although no one has ever observed the actual drop breaking away from the funnel's tip. Learn more about the Pitch Drop experiment and see it in action. Or is that inaction?

Here is the solution:


The best way to keep up with PacSci-Doku, and everything happening at Pacific Science Center, is to subscribe to our free weekly newsletter. Just use the sign-up form below.