🧪 THE PITCH DROP EXPERIMENT🧪
In the world of science, some experiments last days, some weeks—but one experiment has been going on for nearly a century! It’s called the Pitch Drop Experiment, and it holds the title of the longest-running laboratory experiment in history. What makes this experiment so unique is not explosions or high-tech machinery, but simply... watching something drip. Very, very slowly.
What is the Pitch Drop Experiment?
The Pitch Drop Experiment was started in 1927 by Professor Thomas Parnell at the University of Queensland in Australia. The aim was simple: to show that pitch—a black, sticky substance also known as bitumen or tar—though it appears solid, is actually a super-viscous liquid.
To demonstrate this, Professor Parnell heated pitch until it became liquid and poured it into a glass funnel. After allowing it to settle for three years, he cut the funnel’s stem and began observing. What happened next took patience—years of it.
Pitch: Solid or Liquid?
Pitch looks solid. At room temperature, it can be smashed with a hammer. But it is, in fact, a fluid—one that flows so slowly it can take years for a single drop to fall.
To give you an idea, pitch is estimated to be about 100 billion times more viscous than water. That means it flows, just at a pace that’s almost impossible to see in daily life.
How long does a drop take?
Here's a rough timeline of the drops in the University of Queensland experiment:
First drop: Fell in 1938, 11 years after the experiment was set up.
Subsequent drops: Fell at intervals of 8 to 14 years.
Ninth drop: Fell in April 2014.
Even after nearly 100 years, only nine drops have been recorded.
No one saw it fall… At first
Although the drops took years to form and fall, no one actually saw a drop fall live for decades. In 2000, the university set up a webcam to catch the moment—but unfortunately, the camera missed the drop.
It wasn't until 2013, in a similar experiment at Trinity College Dublin, that scientists finally captured the fall of a pitch drop on video for the first time ever. This moment brought renewed global attention to this humble but historic experiment.
Why is it important?
At first glance, this might seem like an odd or even boring experiment. But the Pitch Drop Experiment teaches us several important scientific lessons:
Not everything is as it seems: Materials like pitch may look solid, but behave like liquids over time.
Viscosity matters: Understanding how fluids behave helps us in everything from oil transport to medical science.
Science takes patience: This experiment reminds us that answers sometimes come only after decades of observation.
A World Record in Patience: The Pitch Drop Experiment has earned a place in the Guinness World Records as the longest-running laboratory experiment. It has inspired scientists, educators, and students around the world to look at science not just as instant results, but as a long-term quest for understanding.
Final Thoughts: In an age of fast technology and instant results, the Pitch Drop Experiment is a powerful symbol of slow science. It shows us that even the slowest-moving things can teach us deep truths—if we have the patience to watch and wait.
So the next time you see a drop of water fall from a tap, think of the pitch drop. It took 13 years to do the same thing.
